diff --git a/app/components/ProjectCover.tsx b/app/components/ProjectCover.tsx
index 993f939..852e539 100644
--- a/app/components/ProjectCover.tsx
+++ b/app/components/ProjectCover.tsx
@@ -1,8 +1,13 @@
 import Image from "next/image";
-import { getProjectVideo } from "@/lib/project-videos";
-import { ProjectVideo } from "./ProjectVideo";
+import { getProjectVideo } from "@/lib/project-showcase";
+import { ProjectMedia } from "./showcase/ProjectMedia";
 
-type CoverProject = { id: string; title: string };
+type CoverProject = {
+  id: string;
+  title: string;
+  demoUrl?: string | null;
+  githubUrl?: string | null;
+};
 
 /** Capturas de tela publicadas dos projetos que têm interface pública. */
 const SCREENSHOTS: Record<string, string | undefined> = {
@@ -36,13 +41,7 @@ export function ProjectCover({
   const video = getProjectVideo(project.id);
   const src = SCREENSHOTS[project.id];
 
-  if (video) {
-    return (
-      <div className="ds-cover">
-        <ProjectVideo video={video} title={project.title} />
-      </div>
-    );
-  }
+  if (video) return <ProjectMedia project={project} />;
 
   if (src) {
     return (
diff --git a/app/components/ProjectVideo.test.tsx b/app/components/ProjectVideo.test.tsx
index a4b5405..da1f834 100644
--- a/app/components/ProjectVideo.test.tsx
+++ b/app/components/ProjectVideo.test.tsx
@@ -1,11 +1,5 @@
-import { existsSync, statSync } from "node:fs";
-import { join } from "node:path";
 import { act, render, screen } from "@testing-library/react";
-import {
-  getProjectVideo,
-  PROJECT_VIDEO_IDS,
-  type ProjectVideoAsset,
-} from "@/lib/project-videos";
+import { getShowcaseAssets } from "@/lib/project-showcase";
 import { ProjectVideo } from "./ProjectVideo";
 
 let reducedMotion = false;
@@ -13,59 +7,24 @@ jest.mock("@/app/hooks/useReducedMotion", () => ({
   useReducedMotion: () => reducedMotion,
 }));
 
-const video: ProjectVideoAsset = {
-  poster: "/videos/demo/desktop.webp",
-  width: 1440,
-  height: 900,
-  sources: [
-    { src: "/videos/demo/desktop.webm", type: 'video/webm; codecs="vp9"' },
-    { src: "/videos/demo/desktop.mp4", type: "video/mp4" },
-  ],
-};
-
-type Callback = IntersectionObserverCallback;
-let callbacks: Callback[] = [];
-const originalObserver = global.IntersectionObserver;
+const video = getShowcaseAssets("nutriscan", "desktop");
 
 beforeEach(() => {
   reducedMotion = false;
-  callbacks = [];
-  // observador controlável: o teste decide quando o card entra e sai da tela
-  global.IntersectionObserver = class {
-    constructor(callback: Callback) {
-      callbacks.push(callback);
-    }
-    observe() {}
-    unobserve() {}
-    disconnect() {}
-    takeRecords() {
-      return [];
-    }
-  } as unknown as typeof IntersectionObserver;
   jest.spyOn(HTMLMediaElement.prototype, "play").mockResolvedValue();
   jest.spyOn(HTMLMediaElement.prototype, "pause").mockImplementation(() => {});
   jest.spyOn(HTMLMediaElement.prototype, "load").mockImplementation(() => {});
 });
 
 afterEach(() => {
-  global.IntersectionObserver = originalObserver;
   jest.restoreAllMocks();
 });
 
-function setVisible(isIntersecting: boolean) {
-  act(() => {
-    for (const callback of callbacks) {
-      callback(
-        [{ isIntersecting } as IntersectionObserverEntry],
-        {} as IntersectionObserver,
-      );
-    }
-  });
-}
-
 describe("ProjectVideo", () => {
-  it("renders a muted looping inline video that downloads nothing before it is visible", () => {
-    const { container } = render(<ProjectVideo video={video} title="Demo" />);
+  it("renders a muted looping inline video that downloads nothing until it is active", () => {
+    const { container } = render(
+      <ProjectVideo video={video} title="Demo" active={false} />,
+    );
     const element = container.querySelector("video");
 
     expect(element).not.toBeNull();
@@ -75,29 +34,47 @@ describe("ProjectVideo", () => {
     expect(element).toHaveAttribute("preload", "none");
     expect(element).toHaveAttribute("poster", video.poster);
     expect(element?.muted).toBe(true);
+    expect(element).toHaveAttribute("data-ready", "false");
     expect(container.querySelectorAll("source")).toHaveLength(0);
     expect(HTMLMediaElement.prototype.play).not.toHaveBeenCalled();
   });
 
-  it("attaches the sources and plays once the card enters the viewport, then pauses when it leaves", () => {
-    const { container } = render(<ProjectVideo video={video} title="Demo" />);
+  it("attaches the sources and plays when it becomes the active card, then pauses when it stops being", () => {
+    const { container, rerender } = render(
+      <ProjectVideo video={video} title="Demo" active={false} />,
+    );
 
-    setVisible(true);
+    rerender(<ProjectVideo video={video} title="Demo" active />);
     const sources = [...container.querySelectorAll("source")];
-    expect(sources.map((source) => source.getAttribute("src"))).toEqual([
-      "/videos/demo/desktop.webm",
-      "/videos/demo/desktop.mp4",
-    ]);
+    expect(sources.map((source) => source.getAttribute("src"))).toEqual(
+      video.sources.map((source) => source.src),
+    );
     expect(HTMLMediaElement.prototype.load).toHaveBeenCalled();
     expect(HTMLMediaElement.prototype.play).toHaveBeenCalled();
 
-    setVisible(false);
+    rerender(<ProjectVideo video={video} title="Demo" active={false} />);
     expect(HTMLMediaElement.prototype.pause).toHaveBeenCalled();
+    // sai de cena, mas o arquivo já baixado fica: voltar a tocar não baixa de novo
+    expect(container.querySelectorAll("source")).toHaveLength(2);
+  });
+
+  it("fades the video in once it is playing", () => {
+    const { container } = render(
+      <ProjectVideo video={video} title="Demo" active />,
+    );
+    const element = container.querySelector("video") as HTMLVideoElement;
+
+    act(() => {
+      element.dispatchEvent(new Event("playing"));
+    });
+    expect(element).toHaveAttribute("data-ready", "true");
   });
 
   it("shows only the poster, with no video element, when the user prefers reduced motion", () => {
     reducedMotion = true;
-    const { container } = render(<ProjectVideo video={video} title="Demo" />);
+    const { container } = render(
+      <ProjectVideo video={video} title="Demo" active />,
+    );
 
     expect(container.querySelector("video")).toBeNull();
     expect(
@@ -106,26 +83,3 @@ describe("ProjectVideo", () => {
     expect(HTMLMediaElement.prototype.play).not.toHaveBeenCalled();
   });
 });
-
-describe("getProjectVideo", () => {
-  it("returns undefined for projects without a recorded video", () => {
-    expect(getProjectVideo("reddit-explorer")).toBeUndefined();
-  });
-
-  it.each(PROJECT_VIDEO_IDS)(
-    "has webm, mp4 and poster on disk for %s, each within 3 MB",
-    (id) => {
-      const asset = getProjectVideo(id);
-      expect(asset).toBeDefined();
-      const files = [
-        asset?.poster,
-        ...(asset?.sources.map((s) => s.src) ?? []),
-      ];
-      for (const file of files) {
-        const path = join(process.cwd(), "public", file ?? "");
-        expect(existsSync(path)).toBe(true);
-        expect(statSync(path).size).toBeLessThanOrEqual(3 * 1024 * 1024);
-      }
-    },
-  );
-});
diff --git a/app/components/ProjectVideo.tsx b/app/components/ProjectVideo.tsx
index b38adc8..2e11f24 100644
--- a/app/components/ProjectVideo.tsx
+++ b/app/components/ProjectVideo.tsx
@@ -3,52 +3,48 @@
 import Image from "next/image";
 import { useEffect, useRef, useState } from "react";
 import { useReducedMotion } from "@/app/hooks/useReducedMotion";
-import type { ProjectVideoAsset } from "@/lib/project-videos";
+import type { ShowcaseAssets } from "@/lib/project-showcase";
 
 /**
- * Vídeo de rolagem do projeto na capa do card. Nada de vídeo é baixado até o card entrar na tela
- * (IntersectionObserver); fora da tela ele pausa. Com prefers-reduced-motion só o poster aparece.
+ * Vídeo de rolagem na capa do card. Quem decide se ele toca é a vitrine (`active`: só um card por vez, o que
+ * está sob o mouse ou o mais perto do centro da tela). Nada do vídeo é baixado antes da primeira vez que o
+ * card fica ativo; fora de cena ele pausa. Com prefers-reduced-motion só o poster aparece.
+ * O poster também fica por baixo (fundo da tela da moldura): o vídeo aparece em fade quando começa a tocar.
  */
 export function ProjectVideo({
   video,
   title,
+  active,
 }: {
-  video: ProjectVideoAsset;
+  video: ShowcaseAssets;
   title: string;
+  active: boolean;
 }) {
   const reducedMotion = useReducedMotion();
   const ref = useRef<HTMLVideoElement>(null);
-  const [activated, setActivated] = useState(false);
+  const [attached, setAttached] = useState(false);
+  const [ready, setReady] = useState(false);
+  const playing = active && !reducedMotion;
+
+  useEffect(() => {
+    if (playing) setAttached(true);
+  }, [playing]);
+
+  useEffect(() => {
+    // as fontes entram depois do primeiro render: o elemento precisa ler a lista nova
+    if (attached) ref.current?.load();
+  }, [attached]);
 
   useEffect(() => {
     const element = ref.current;
-    if (reducedMotion || !element) return;
-    if (typeof IntersectionObserver === "undefined") {
-      setActivated(true);
-      return;
+    if (!element || !attached) return;
+    if (playing) {
+      element.muted = true; // o React não reflete `muted` no DOM e o autoplay exige o valor real
+      element.play().catch(() => {});
+    } else {
+      element.pause(); // também cancela um autoplay que ainda esperava o arquivo chegar
     }
-    const observer = new IntersectionObserver(
-      ([entry]) => {
-        if (entry?.isIntersecting) {
-          setActivated(true);
-          element.play().catch(() => {});
-        } else {
-          element.pause();
-        }
-      },
-      { rootMargin: "120px 0px", threshold: 0.2 },
-    );
-    observer.observe(element);
-    return () => observer.disconnect();
-  }, [reducedMotion]);
-
-  useEffect(() => {
-    const element = ref.current;
-    if (!activated || reducedMotion || !element) return;
-    element.muted = true; // o React não reflete `muted` no DOM e o autoplay exige o valor real
-    element.load();
-    element.play().catch(() => {});
-  }, [activated, reducedMotion]);
+  }, [attached, playing]);
 
   if (reducedMotion) {
     return (
@@ -73,11 +69,13 @@ export function ProjectVideo({
       poster={video.poster}
       width={video.width}
       height={video.height}
+      data-ready={ready}
+      onPlaying={() => setReady(true)}
       aria-label={`Demonstração em vídeo de ${title}`}
       disablePictureInPicture
       disableRemotePlayback
     >
-      {activated &&
+      {attached &&
         video.sources.map((source) => (
           <source key={source.src} src={source.src} type={source.type} />
         ))}
diff --git a/app/components/showcase/BrowserFrame.test.tsx b/app/components/showcase/BrowserFrame.test.tsx
new file mode 100644
index 0000000..84fc83e
--- /dev/null
+++ b/app/components/showcase/BrowserFrame.test.tsx
@@ -0,0 +1,86 @@
+import { render, screen } from "@testing-library/react";
+import { BrowserFrame, displayUrl } from "./BrowserFrame";
+
+describe("displayUrl", () => {
+  it("shows the site address without the protocol, www or trailing slash", () => {
+    expect(displayUrl({ demoUrl: "https://www.example.com.br/" })).toEqual({
+      text: "example.com.br",
+      secure: true,
+    });
+    expect(displayUrl({ demoUrl: "https://app.example.com/painel/" })).toEqual({
+      text: "app.example.com/painel",
+      secure: true,
+    });
+  });
+
+  it("marks plain http as not secure", () => {
+    expect(displayUrl({ demoUrl: "http://localhost:3000" })).toEqual({
+      text: "localhost:3000",
+      secure: false,
+    });
+  });
+
+  it("falls back to the code address when there is no live demo", () => {
+    expect(
+      displayUrl({ demoUrl: null, githubUrl: "https://github.com/user/repo" }),
+    ).toEqual({ text: "github.com/user/repo", secure: true });
+  });
+
+  it("skips an address that does not parse and uses the next one", () => {
+    expect(
+      displayUrl({
+        demoUrl: "isso não é uma url",
+        githubUrl: "https://github.com/a/b",
+      }),
+    ).toEqual({ text: "github.com/a/b", secure: true });
+  });
+
+  it("returns null when there is nothing to show", () => {
+    expect(displayUrl({})).toBeNull();
+    expect(displayUrl({ demoUrl: "", githubUrl: null })).toBeNull();
+  });
+});
+
+describe("BrowserFrame", () => {
+  it("draws the three dots, the address and the screen content", () => {
+    const { container } = render(
+      <BrowserFrame url={{ text: "site.com", secure: true }}>
+        <p>conteúdo</p>
+      </BrowserFrame>,
+    );
+
+    expect(screen.getByText("site.com")).toBeInTheDocument();
+    expect(screen.getByText("conteúdo")).toBeInTheDocument();
+    expect(container.querySelectorAll(".ds-bframe-dots i")).toHaveLength(3);
+    expect(container.querySelector(".ds-bframe-url svg")).not.toBeNull();
+  });
+
+  it("keeps the decorative bar out of the accessibility tree", () => {
+    const { container } = render(
+      <BrowserFrame url={{ text: "site.com", secure: true }}>
+        <p>x</p>
+      </BrowserFrame>,
+    );
+    expect(container.querySelector(".ds-bframe-bar")).toHaveAttribute(
+      "aria-hidden",
+      "true",
+    );
+  });
+
+  it("shows a neutral label and no lock when the address is unknown or not secure", () => {
+    const { container, rerender } = render(
+      <BrowserFrame url={null}>
+        <p>x</p>
+      </BrowserFrame>,
+    );
+    expect(screen.getByText("pré-visualização")).toBeInTheDocument();
+    expect(container.querySelector(".ds-bframe-url svg")).toBeNull();
+
+    rerender(
+      <BrowserFrame url={{ text: "localhost", secure: false }}>
+        <p>x</p>
+      </BrowserFrame>,
+    );
+    expect(container.querySelector(".ds-bframe-url svg")).toBeNull();
+  });
+});
diff --git a/app/components/showcase/BrowserFrame.tsx b/app/components/showcase/BrowserFrame.tsx
new file mode 100644
index 0000000..86866b2
--- /dev/null
+++ b/app/components/showcase/BrowserFrame.tsx
@@ -0,0 +1,66 @@
+import type { CSSProperties, ReactNode } from "react";
+
+/** Endereço mostrado na barra: o do site publicado, ou o do código quando não há demonstração. */
+export function displayUrl(project: {
+  demoUrl?: string | null;
+  githubUrl?: string | null;
+}): { text: string; secure: boolean } | null {
+  for (const raw of [project.demoUrl, project.githubUrl]) {
+    if (!raw) continue;
+    try {
+      const url = new URL(raw);
+      const path = url.pathname === "/" ? "" : url.pathname.replace(/\/$/, "");
+      return {
+        text: `${url.host.replace(/^www\./, "")}${path}`,
+        secure: url.protocol === "https:",
+      };
+    } catch {}
+  }
+  return null;
+}
+
+/**
+ * Janela de navegador em volta da captura: três pontos, barra com o endereço real e a tela.
+ * A barra é decoração (aria-hidden); o endereço também aparece como texto no próprio card.
+ */
+export function BrowserFrame({
+  url,
+  children,
+  className = "",
+  style,
+}: {
+  url: { text: string; secure: boolean } | null;
+  children: ReactNode;
+  className?: string;
+  style?: CSSProperties;
+}) {
+  return (
+    <div className={`ds-bframe ${className}`.trim()} style={style}>
+      <div className="ds-bframe-bar" aria-hidden="true">
+        <span className="ds-bframe-dots">
+          <i />
+          <i />
+          <i />
+        </span>
+        <span className="ds-bframe-url">
+          {url?.secure && (
+            <svg
+              viewBox="0 0 12 12"
+              width="10"
+              height="10"
+              fill="none"
+              stroke="currentColor"
+              strokeWidth="1.4"
+              aria-hidden="true"
+            >
+              <rect x="2.5" y="5.5" width="7" height="5" />
+              <path d="M4 5.5V4a2 2 0 0 1 4 0v1.5" />
+            </svg>
+          )}
+          <span>{url?.text ?? "pré-visualização"}</span>
+        </span>
+      </div>
+      {children}
+    </div>
+  );
+}
diff --git a/app/components/showcase/PhoneFrame.tsx b/app/components/showcase/PhoneFrame.tsx
new file mode 100644
index 0000000..808e820
--- /dev/null
+++ b/app/components/showcase/PhoneFrame.tsx
@@ -0,0 +1,25 @@
+import type { CSSProperties, ReactNode } from "react";
+
+/** Moldura de celular para o vídeo mobile (proporção 390x844 do vídeo; o recorte da tela segue a mesma conta). */
+export function PhoneFrame({
+  children,
+  poster,
+  className = "",
+  style,
+}: {
+  children: ReactNode;
+  poster?: string;
+  className?: string;
+  style?: CSSProperties;
+}) {
+  return (
+    <div className={`ds-phone ${className}`.trim()} style={style}>
+      <div
+        className="ds-phone-screen"
+        style={poster ? { backgroundImage: `url(${poster})` } : undefined}
+      >
+        {children}
+      </div>
+    </div>
+  );
+}
diff --git a/app/components/showcase/ProjectLightbox.test.tsx b/app/components/showcase/ProjectLightbox.test.tsx
new file mode 100644
index 0000000..1ffb082
--- /dev/null
+++ b/app/components/showcase/ProjectLightbox.test.tsx
@@ -0,0 +1,393 @@
+import {
+  act,
+  cleanup,
+  fireEvent,
+  render,
+  screen,
+  within,
+} from "@testing-library/react";
+import { StrictMode } from "react";
+import { getFeaturedProjects } from "@/lib/portfolio-data";
+import {
+  chapterFraction,
+  getShowcaseConfig,
+  mobileFractionAt,
+} from "@/lib/project-showcase";
+import { ShowcaseProvider, useShowcaseCard } from "./ShowcaseProvider";
+
+let reducedMotion = false;
+jest.mock("@/app/hooks/useReducedMotion", () => ({
+  useReducedMotion: () => reducedMotion,
+}));
+
+function Card({ id }: { id: string }) {
+  const { frameRef, open } = useShowcaseCard(id);
+  return (
+    <article className="ds-card">
+      <div ref={frameRef} />
+      <button type="button" onClick={open}>
+        ampliar {id}
+      </button>
+    </article>
+  );
+}
+
+const projects = getFeaturedProjects(null);
+const lavacao = getShowcaseConfig("lavacao-047");
+
+function setup(id = "lavacao-047") {
+  render(
+    <ShowcaseProvider projects={projects}>
+      <Card id="sev-modaintima" />
+      <Card id="lavacao-047" />
+      <Card id="nutriscan" />
+      <Card id="as-servicos" />
+    </ShowcaseProvider>,
+  );
+  fireEvent.click(screen.getByRole("button", { name: `ampliar ${id}` }));
+  return screen.getByRole("dialog");
+}
+
+/** jsdom não carrega mídia: o teste dá ao <video> uma duração e deixa o componente reagir como no navegador. */
+function loadVideo(dialog: HTMLElement, duration = 30) {
+  const video = dialog.querySelector("video") as HTMLVideoElement;
+  Object.defineProperty(video, "duration", {
+    configurable: true,
+    value: duration,
+  });
+  let time = 0;
+  Object.defineProperty(video, "currentTime", {
+    configurable: true,
+    get: () => time,
+    set: (value: number) => {
+      time = value;
+    },
+  });
+  act(() => {
+    video.dispatchEvent(new Event("loadedmetadata"));
+  });
+  return video;
+}
+
+beforeAll(() => {
+  window.matchMedia = jest.fn().mockImplementation((query: string) => ({
+    matches: false,
+    media: query,
+    addEventListener() {},
+    removeEventListener() {},
+  }));
+  // jsdom ainda não implementa o <dialog> modal
+  HTMLDialogElement.prototype.showModal = function showModal(
+    this: HTMLDialogElement,
+  ) {
+    this.setAttribute("open", "");
+  };
+  HTMLDialogElement.prototype.close = function close(this: HTMLDialogElement) {
+    this.removeAttribute("open");
+    this.dispatchEvent(new Event("close"));
+  };
+});
+
+beforeEach(() => {
+  reducedMotion = false;
+  jest
+    .spyOn(HTMLMediaElement.prototype, "play")
+    .mockImplementation(function play(this: HTMLMediaElement) {
+      // jsdom não toca nada: o teste mantém `paused` e os eventos como o navegador faria
+      Object.defineProperty(this, "paused", {
+        configurable: true,
+        value: false,
+      });
+      this.dispatchEvent(new Event("play"));
+      return Promise.resolve();
+    });
+  jest
+    .spyOn(HTMLMediaElement.prototype, "pause")
+    .mockImplementation(function pause(this: HTMLMediaElement) {
+      Object.defineProperty(this, "paused", {
+        configurable: true,
+        value: true,
+      });
+      this.dispatchEvent(new Event("pause"));
+    });
+});
+
+afterEach(() => {
+  jest.restoreAllMocks();
+  document.documentElement.classList.remove("ds-lb-open");
+});
+
+describe("ProjectLightbox", () => {
+  it("opens a modal dialog for the clicked project, locks page scroll and puts focus on close", () => {
+    const dialog = setup();
+
+    expect(dialog).toHaveAttribute("open");
+    expect(dialog).toHaveAccessibleName("Lavação 047");
+    expect(dialog).toHaveAttribute("data-lenis-prevent");
+    expect(document.documentElement).toHaveClass("ds-lb-open");
+    expect(
+      within(dialog).getByRole("button", { name: "Fechar" }),
+    ).toHaveFocus();
+    expect(within(dialog).getByText("02 / 05")).toBeInTheDocument();
+  });
+
+  it("shows the desktop video in a browser frame by default and the phone version on request", () => {
+    const dialog = setup();
+    const toggle = within(dialog).getByRole("group", {
+      name: "Versão do site",
+    });
+
+    expect(
+      within(toggle).getByRole("button", { name: "Computador" }),
+    ).toHaveAttribute("aria-pressed", "true");
+    expect(dialog.querySelector(".ds-lb-frame")).not.toBeNull();
+    expect(dialog.querySelector('source[src$="desktop.webm"]')).not.toBeNull();
+
+    fireEvent.click(within(toggle).getByRole("button", { name: "Celular" }));
+    expect(
+      within(toggle).getByRole("button", { name: "Celular" }),
+    ).toHaveAttribute("aria-pressed", "true");
+    expect(dialog.querySelector(".ds-lb-phone")).not.toBeNull();
+    expect(dialog.querySelector('source[src$="mobile.webm"]')).not.toBeNull();
+  });
+
+  it("keeps the same point of the site when switching devices", () => {
+    if (!lavacao) throw new Error("config ausente");
+    const dialog = setup();
+    const desktop = loadVideo(dialog, lavacao.durations.desktop);
+
+    // meio do vídeo desktop
+    desktop.currentTime = lavacao.durations.desktop * 0.5;
+    fireEvent.click(within(dialog).getByRole("button", { name: "Celular" }));
+    const phone = loadVideo(dialog, lavacao.durations.mobile);
+
+    expect(phone.currentTime).toBeCloseTo(
+      mobileFractionAt(lavacao, 0.5) * lavacao.durations.mobile,
+      5,
+    );
+  });
+
+  it("jumps to a chapter and marks it as current", () => {
+    if (!lavacao) throw new Error("config ausente");
+    const dialog = setup();
+    const video = loadVideo(dialog, lavacao.durations.desktop);
+
+    fireEvent.click(
+      within(dialog).getByRole("button", { name: /Do sujo ao brilho/ }),
+    );
+
+    expect(video.currentTime).toBeCloseTo(
+      chapterFraction(lavacao, 2, "desktop") * lavacao.durations.desktop,
+      5,
+    );
+    expect(
+      within(dialog).getByRole("button", { name: /Do sujo ao brilho/ }),
+    ).toHaveAttribute("aria-current", "true");
+  });
+
+  it("toggles play and pause with an accessible name", () => {
+    const dialog = setup();
+    loadVideo(dialog);
+
+    const play = within(dialog).getByRole("button", { name: "Reproduzir" });
+    fireEvent.click(play);
+    expect(
+      within(dialog).getByRole("button", { name: "Pausar" }),
+    ).toBeInTheDocument();
+    fireEvent.click(within(dialog).getByRole("button", { name: "Pausar" }));
+    expect(
+      within(dialog).getByRole("button", { name: "Reproduzir" }),
+    ).toBeInTheDocument();
+  });
+
+  it("seeks with the range slider", () => {
+    const dialog = setup();
+    const video = loadVideo(dialog, 30);
+
+    fireEvent.change(
+      within(dialog).getByRole("slider", { name: "Posição do vídeo" }),
+      { target: { value: "500" } },
+    );
+    expect(video.currentTime).toBeCloseTo(15, 5);
+  });
+
+  it("moves between projects and disables the arrows at both ends", () => {
+    const dialog = setup("sev-modaintima");
+    expect(
+      within(dialog).getByRole("button", { name: "Projeto anterior" }),
+    ).toBeDisabled();
+
+    fireEvent.click(
+      within(dialog).getByRole("button", { name: "Próximo projeto" }),
+    );
+    expect(screen.getByRole("dialog")).toHaveAccessibleName("Lavação 047");
+
+    fireEvent.keyDown(screen.getByRole("dialog"), { key: "ArrowLeft" });
+    expect(screen.getByRole("dialog")).toHaveAccessibleName("SEV Moda Íntima");
+  });
+
+  it("offers the site and the code when they exist", () => {
+    const dialog = setup("lavacao-047");
+    expect(
+      within(dialog).getByRole("link", { name: /Abrir projeto/ }),
+    ).toHaveAttribute("href", "https://landing-page-lavacao047.vercel.app");
+    expect(
+      within(dialog).queryByRole("link", { name: /Ver codigo/ }),
+    ).toBeNull();
+  });
+
+  it("closes with the close button, with the backdrop or with Esc, and unlocks the page", () => {
+    setup();
+    fireEvent.click(screen.getByRole("button", { name: "Fechar" }));
+    expect(screen.queryByRole("dialog")).toBeNull();
+    expect(document.documentElement).not.toHaveClass("ds-lb-open");
+
+    cleanup();
+    const dialog = setup();
+    fireEvent.pointerDown(dialog);
+    fireEvent.click(dialog); // clique no fundo (o próprio <dialog>)
+    expect(screen.queryByRole("dialog")).toBeNull();
+
+    cleanup();
+    const again = setup();
+    act(() => {
+      again.removeAttribute("open"); // o Esc nativo fecha o <dialog> e só então dispara `close`
+      again.dispatchEvent(new Event("close"));
+    });
+    expect(screen.queryByRole("dialog")).toBeNull();
+    expect(document.documentElement).not.toHaveClass("ds-lb-open");
+  });
+
+  it("does not autoplay for users who prefer reduced motion", () => {
+    reducedMotion = true;
+    const dialog = setup();
+    expect(dialog.querySelector("video")).not.toHaveAttribute("autoplay");
+  });
+});
+
+describe("ProjectLightbox: revisão", () => {
+  it("survives React StrictMode in development: the double effect must not close the window it just opened", () => {
+    // o `close` real é assíncrono: o teste reproduz isso para pegar o evento atrasado
+    HTMLDialogElement.prototype.close = function close(
+      this: HTMLDialogElement,
+    ) {
+      this.removeAttribute("open");
+      queueMicrotask(() => this.dispatchEvent(new Event("close")));
+    };
+    jest.useFakeTimers();
+    try {
+      render(
+        <StrictMode>
+          <ShowcaseProvider projects={projects}>
+            <Card id="lavacao-047" />
+          </ShowcaseProvider>
+        </StrictMode>,
+      );
+      fireEvent.click(
+        screen.getByRole("button", { name: "ampliar lavacao-047" }),
+      );
+      act(() => {
+        jest.advanceTimersByTime(50);
+      });
+      expect(screen.getByRole("dialog")).toHaveAttribute("open");
+    } finally {
+      jest.useRealTimers();
+      HTMLDialogElement.prototype.close = function close(
+        this: HTMLDialogElement,
+      ) {
+        this.removeAttribute("open");
+        this.dispatchEvent(new Event("close"));
+      };
+    }
+  });
+
+  it("ignores a late close event from a dialog that is open again", () => {
+    const dialog = setup();
+    act(() => {
+      dialog.dispatchEvent(new Event("close"));
+    });
+    expect(screen.getByRole("dialog")).toBeInTheDocument();
+  });
+
+  it("does not close when a press starts inside the panel and is released on the backdrop", () => {
+    const dialog = setup();
+    fireEvent.pointerDown(
+      within(dialog).getByRole("slider", { name: "Posição do vídeo" }),
+    );
+    fireEvent.click(dialog);
+    expect(screen.getByRole("dialog")).toBeInTheDocument();
+  });
+
+  it("stays paused after switching device when the visitor had paused", () => {
+    const dialog = setup();
+    loadVideo(dialog);
+    fireEvent.click(within(dialog).getByRole("button", { name: "Reproduzir" }));
+    fireEvent.click(within(dialog).getByRole("button", { name: "Pausar" }));
+
+    fireEvent.click(within(dialog).getByRole("button", { name: "Celular" }));
+    expect(dialog.querySelector("video")).not.toHaveAttribute("autoplay");
+    expect(
+      within(dialog).getByRole("button", { name: "Reproduzir" }),
+    ).toBeInTheDocument();
+  });
+
+  it("keeps playing after switching device when the video was playing", () => {
+    const dialog = setup();
+    loadVideo(dialog);
+    fireEvent.click(within(dialog).getByRole("button", { name: "Reproduzir" }));
+
+    fireEvent.click(within(dialog).getByRole("button", { name: "Celular" }));
+    expect(dialog.querySelector("video")).toHaveAttribute("autoplay");
+  });
+
+  it("keeps the position when the visitor flips the device twice before the new video loads", () => {
+    if (!lavacao) throw new Error("config ausente");
+    const dialog = setup();
+    const desktop = loadVideo(dialog, lavacao.durations.desktop);
+    desktop.currentTime = lavacao.durations.desktop * 0.5;
+
+    fireEvent.click(within(dialog).getByRole("button", { name: "Celular" }));
+    // o vídeo do celular ainda não carregou (sem duração): volta de novo para o computador
+    fireEvent.click(within(dialog).getByRole("button", { name: "Computador" }));
+    const back = loadVideo(dialog, lavacao.durations.desktop);
+
+    expect(back.currentTime / lavacao.durations.desktop).toBeCloseTo(0.5, 1);
+  });
+
+  it("moves focus to the opposite arrow when the pressed one reaches its end", () => {
+    const dialog = setup("nutriscan");
+    // anterior, anterior: chega ao primeiro e o botão "Anterior" fica desabilitado
+    let current = within(dialog).getByRole("button", {
+      name: "Projeto anterior",
+    });
+    current.focus();
+    fireEvent.click(current);
+    current = within(screen.getByRole("dialog")).getByRole("button", {
+      name: "Projeto anterior",
+    });
+    current.focus();
+    fireEvent.click(current);
+
+    const after = within(screen.getByRole("dialog"));
+    expect(screen.getByRole("dialog")).toHaveAccessibleName("SEV Moda Íntima");
+    expect(
+      after.getByRole("button", { name: "Projeto anterior" }),
+    ).toBeDisabled();
+    expect(
+      after.getByRole("button", { name: "Próximo projeto" }),
+    ).toHaveFocus();
+  });
+
+  it("announces which project is on screen", () => {
+    const dialog = setup("nutriscan");
+    expect(dialog.querySelector("[aria-live='polite']")).toHaveTextContent(
+      "NutriScan, projeto 3 de 5",
+    );
+  });
+
+  it("ignores arrow keys combined with modifiers, which belong to the browser", () => {
+    const dialog = setup("lavacao-047");
+    fireEvent.keyDown(dialog, { key: "ArrowRight", altKey: true });
+    expect(screen.getByRole("dialog")).toHaveAccessibleName("Lavação 047");
+  });
+});
diff --git a/app/components/showcase/ProjectLightbox.tsx b/app/components/showcase/ProjectLightbox.tsx
new file mode 100644
index 0000000..4e4b3a1
--- /dev/null
+++ b/app/components/showcase/ProjectLightbox.tsx
@@ -0,0 +1,400 @@
+"use client";
+
+import {
+  type ChangeEvent,
+  type CSSProperties,
+  type KeyboardEvent,
+  type MouseEvent,
+  type PointerEvent,
+  useCallback,
+  useEffect,
+  useId,
+  useRef,
+  useState,
+} from "react";
+import { useReducedMotion } from "@/app/hooks/useReducedMotion";
+import {
+  chapterFraction,
+  chapterIndexAt,
+  type Device,
+  desktopFractionAt,
+  getShowcaseAssets,
+  mobileFractionAt,
+} from "@/lib/project-showcase";
+import { BrowserFrame, displayUrl } from "./BrowserFrame";
+import { PhoneFrame } from "./PhoneFrame";
+import type { ShowcaseItem } from "./ShowcaseProvider";
+
+const formatTime = (seconds: number) => {
+  const whole = Math.max(0, Math.floor(seconds));
+  return `${Math.floor(whole / 60)}:${String(whole % 60).padStart(2, "0")}`;
+};
+
+/**
+ * Vídeo ampliado: janela modal nativa (<dialog>: foco preso, Esc fecha, foco volta ao botão que abriu),
+ * com troca desktop/celular que mantém o ponto do site, capítulos clicáveis e controles próprios.
+ */
+export function ProjectLightbox({
+  items,
+  index,
+  onClose,
+  onNavigate,
+}: {
+  items: ShowcaseItem[];
+  index: number;
+  onClose: () => void;
+  onNavigate: (index: number) => void;
+}) {
+  const { config, project } = items[index];
+  const reducedMotion = useReducedMotion();
+  const titleId = useId();
+  const dialogRef = useRef<HTMLDialogElement>(null);
+  const videoRef = useRef<HTMLVideoElement>(null);
+  const closeRef = useRef<HTMLButtonElement>(null);
+  const previousRef = useRef<HTMLButtonElement>(null);
+  const nextRef = useRef<HTMLButtonElement>(null);
+  const pendingFraction = useRef<number | null>(null);
+  const pressedOnBackdrop = useRef(false);
+
+  const [device, setDevice] = useState<Device>(() =>
+    window.matchMedia("(max-width: 639px)").matches ? "mobile" : "desktop",
+  );
+  // o vídeo de cada aparelho/projeto nasce tocando só se o visitante não pausou e não pediu menos movimento
+  const [autoplay, setAutoplay] = useState(
+    () => !window.matchMedia("(prefers-reduced-motion: reduce)").matches,
+  );
+  const wantsToPlay = useRef(autoplay);
+  const [playing, setPlaying] = useState(false);
+  const [fraction, setFraction] = useState(0);
+  const [duration, setDuration] = useState(0);
+
+  useEffect(() => {
+    if (!reducedMotion) return;
+    wantsToPlay.current = false;
+    setAutoplay(false);
+  }, [reducedMotion]);
+
+  useEffect(() => {
+    const dialog = dialogRef.current;
+    if (!dialog) return;
+    if (!dialog.open) dialog.showModal();
+    closeRef.current?.focus();
+    // travar a rolagem da página tira a barra de rolagem clássica: o espaço dela é devolvido para nada pular
+    const root = document.documentElement;
+    root.style.setProperty(
+      "--ds-scrollbar",
+      `${Math.max(0, window.innerWidth - root.clientWidth)}px`,
+    );
+    root.classList.add("ds-lb-open");
+    return () => {
+      root.classList.remove("ds-lb-open");
+      root.style.removeProperty("--ds-scrollbar");
+      // sem dialog.close() aqui: no StrictMode do dev a limpeza roda no meio da abertura e o evento `close`
+      // (assíncrono) chegaria depois de reaberto; sair do DOM já basta para soltar a janela modal
+    };
+  }, []);
+
+  // o marcador acompanha o vídeo quadro a quadro enquanto ele toca (timeupdate só chega umas 4 vezes por segundo)
+  useEffect(() => {
+    if (!playing) return;
+    let id = 0;
+    const tick = () => {
+      const current = videoRef.current;
+      if (current?.duration)
+        setFraction(current.currentTime / current.duration);
+      id = requestAnimationFrame(tick);
+    };
+    id = requestAnimationFrame(tick);
+    return () => cancelAnimationFrame(id);
+  }, [playing]);
+
+  const assets = getShowcaseAssets(config.id, device);
+  const desktopFraction =
+    device === "desktop" ? fraction : desktopFractionAt(config, fraction);
+  const chapter = chapterIndexAt(config, desktopFraction);
+  const url = displayUrl(project);
+  const canOpenSite =
+    project.demoUrl &&
+    (project.demoAvailability === "available" ||
+      project.demoAvailability === "unknown");
+
+  const switchDevice = (next: Device) => {
+    if (next === device) return;
+    const video = videoRef.current;
+    // se o novo vídeo ainda não tem duração (duplo clique), vale a posição já gravada no estado
+    const current = video?.duration
+      ? video.currentTime / video.duration
+      : fraction;
+    pendingFraction.current =
+      next === "mobile"
+        ? mobileFractionAt(config, current)
+        : desktopFractionAt(config, current);
+    setFraction(pendingFraction.current);
+    setPlaying(false);
+    setAutoplay(wantsToPlay.current);
+    setDevice(next);
+  };
+
+  const navigate = (next: number) => {
+    if (next < 0 || next >= items.length) return;
+    pendingFraction.current = null;
+    setFraction(0);
+    setPlaying(false);
+    setAutoplay(wantsToPlay.current);
+    // o botão que acabou de chegar ao limite fica desabilitado: o foco passa para o do outro lado
+    const active = document.activeElement;
+    if (active === previousRef.current && next === 0) nextRef.current?.focus();
+    if (active === nextRef.current && next === items.length - 1)
+      previousRef.current?.focus();
+    onNavigate(next);
+  };
+
+  const handleMetadata = () => {
+    const video = videoRef.current;
+    if (!video) return;
+    setDuration(video.duration);
+    if (pendingFraction.current !== null) {
+      video.currentTime = pendingFraction.current * video.duration;
+      pendingFraction.current = null;
+    }
+  };
+
+  const handleTime = () => {
+    const video = videoRef.current;
+    if (video?.duration) setFraction(video.currentTime / video.duration);
+  };
+
+  const togglePlay = () => {
+    const video = videoRef.current;
+    if (!video) return;
+    wantsToPlay.current = video.paused;
+    if (video.paused) video.play().catch(() => {});
+    else video.pause();
+  };
+
+  const seekTo = useCallback((next: number) => {
+    const video = videoRef.current;
+    if (!video?.duration) return;
+    video.currentTime = Math.min(1, Math.max(0, next)) * video.duration;
+    setFraction(next);
+  }, []);
+
+  const onKeyDown = (event: KeyboardEvent<HTMLDialogElement>) => {
+    if (event.target instanceof HTMLInputElement) return;
+    // Alt+Seta é "voltar/avançar" do navegador
+    if (event.altKey || event.ctrlKey || event.metaKey || event.shiftKey)
+      return;
+    if (event.key === "ArrowLeft") navigate(index - 1);
+    if (event.key === "ArrowRight") navigate(index + 1);
+  };
+
+  // clique no fundo escuro fecha, mas só se o toque também começou nele (arrastar a barra de posição e soltar fora não conta)
+  const onBackdropPointerDown = (event: PointerEvent<HTMLDialogElement>) => {
+    pressedOnBackdrop.current = event.target === event.currentTarget;
+  };
+  const onBackdropClick = (event: MouseEvent<HTMLDialogElement>) => {
+    if (event.target === event.currentTarget && pressedOnBackdrop.current)
+      dialogRef.current?.close();
+    pressedOnBackdrop.current = false;
+  };
+
+  const video = (
+    // biome-ignore lint/a11y/useMediaCaption: demonstração sem áudio; a descrição está no título e nos capítulos
+    <video
+      key={`${config.id}-${device}`}
+      ref={videoRef}
+      className="ds-lb-video"
+      autoPlay={autoplay}
+      muted
+      loop
+      playsInline
+      preload="auto"
+      poster={assets.poster}
+      width={assets.width}
+      height={assets.height}
+      onLoadedMetadata={handleMetadata}
+      onPlay={() => setPlaying(true)}
+      onPause={() => setPlaying(false)}
+      onTimeUpdate={handleTime}
+      aria-label={`Vídeo de ${project.title}, versão ${device === "desktop" ? "para computador" : "para celular"}`}
+    >
+      {assets.sources.map((source) => (
+        <source key={source.src} src={source.src} type={source.type} />
+      ))}
+    </video>
+  );
+
+  return (
+    <dialog
+      ref={dialogRef}
+      className="ds-lb"
+      aria-labelledby={titleId}
+      data-lenis-prevent
+      style={{ "--accent": config.accent } as CSSProperties}
+      onClose={(event) => {
+        // um `close` atrasado de uma janela que já foi reaberta (StrictMode) não pode fechar a nova
+        if (!event.currentTarget.open) onClose();
+      }}
+      onPointerDown={onBackdropPointerDown}
+      onClick={onBackdropClick}
+      onKeyDown={onKeyDown}
+    >
+      <div className="ds-lb-panel">
+        <p className="sr-only" aria-live="polite">
+          {`${project.title}, projeto ${index + 1} de ${items.length}`}
+        </p>
+        <header className="ds-lb-head">
+          <div className="ds-lb-heading">
+            <p className="ds-lb-count">
+              {String(index + 1).padStart(2, "0")} /{" "}
+              {String(items.length).padStart(2, "0")}
+            </p>
+            <h3 id={titleId} className="ds-lb-title">
+              {project.title}
+            </h3>
+          </div>
+
+          <fieldset className="ds-lb-toggle">
+            <legend className="sr-only">Versão do site</legend>
+            {(["desktop", "mobile"] as const).map((option) => (
+              <button
+                key={option}
+                type="button"
+                aria-pressed={device === option}
+                onClick={() => switchDevice(option)}
+              >
+                {option === "desktop" ? "Computador" : "Celular"}
+              </button>
+            ))}
+          </fieldset>
+
+          <div className="ds-lb-nav">
+            <button
+              ref={previousRef}
+              type="button"
+              onClick={() => navigate(index - 1)}
+              disabled={index === 0}
+              aria-label="Projeto anterior"
+            >
+              <svg viewBox="0 0 16 16" aria-hidden="true">
+                <path d="M10 3 5 8l5 5" />
+              </svg>
+            </button>
+            <button
+              ref={nextRef}
+              type="button"
+              onClick={() => navigate(index + 1)}
+              disabled={index === items.length - 1}
+              aria-label="Próximo projeto"
+            >
+              <svg viewBox="0 0 16 16" aria-hidden="true">
+                <path d="m6 3 5 5-5 5" />
+              </svg>
+            </button>
+            <button
+              ref={closeRef}
+              type="button"
+              className="ds-lb-close"
+              onClick={() => dialogRef.current?.close()}
+              aria-label="Fechar"
+            >
+              <svg viewBox="0 0 16 16" aria-hidden="true">
+                <path d="m3 3 10 10M13 3 3 13" />
+              </svg>
+            </button>
+          </div>
+        </header>
+
+        <div className="ds-lb-stage" data-device={device}>
+          {device === "desktop" ? (
+            <BrowserFrame url={url} className="ds-lb-frame">
+              <div
+                className="ds-lb-screen"
+                style={{ backgroundImage: `url(${assets.poster})` }}
+              >
+                {video}
+              </div>
+            </BrowserFrame>
+          ) : (
+            <PhoneFrame className="ds-lb-phone" poster={assets.poster}>
+              {video}
+            </PhoneFrame>
+          )}
+        </div>
+
+        <div className="ds-lb-controls">
+          <button
+            type="button"
+            className="ds-lb-play"
+            onClick={togglePlay}
+            aria-label={playing ? "Pausar" : "Reproduzir"}
+          >
+            <svg viewBox="0 0 16 16" aria-hidden="true">
+              {playing ? (
+                <path d="M4 3h3v10H4zM9 3h3v10H9z" />
+              ) : (
+                <path d="M4 2.5v11l9-5.5z" />
+              )}
+            </svg>
+          </button>
+          <span className="ds-lb-time" aria-hidden="true">
+            {formatTime(fraction * duration)} / {formatTime(duration)}
+          </span>
+          <input
+            type="range"
+            className="ds-lb-range"
+            min={0}
+            max={1000}
+            step={1}
+            value={Math.round(fraction * 1000)}
+            onChange={(event: ChangeEvent<HTMLInputElement>) =>
+              seekTo(Number(event.target.value) / 1000)
+            }
+            aria-label="Posição do vídeo"
+            aria-valuetext={`${formatTime(fraction * duration)} de ${formatTime(duration)}`}
+          />
+        </div>
+
+        <ol className="ds-lb-chapters" aria-label="Trechos do site">
+          {config.chapters.map((entry, i) => (
+            <li key={entry.label}>
+              <button
+                type="button"
+                aria-current={i === chapter ? "true" : undefined}
+                onClick={() => seekTo(chapterFraction(config, i, device))}
+              >
+                <span aria-hidden="true">{String(i + 1).padStart(2, "0")}</span>{" "}
+                {entry.label}
+              </button>
+            </li>
+          ))}
+        </ol>
+
+        <div className="ds-lb-links">
+          {canOpenSite && (
+            <a
+              className="ds-link ds-link-accent"
+              href={project.demoUrl ?? undefined}
+              target="_blank"
+              rel="noreferrer"
+            >
+              Abrir projeto
+              <span className="sr-only"> (abre em nova aba)</span>
+            </a>
+          )}
+          {project.githubUrl && (
+            <a
+              className="ds-link ds-link-muted"
+              href={project.githubUrl}
+              target="_blank"
+              rel="noreferrer"
+            >
+              Ver codigo
+              <span className="sr-only"> (abre em nova aba)</span>
+            </a>
+          )}
+        </div>
+      </div>
+    </dialog>
+  );
+}
diff --git a/app/components/showcase/ProjectMedia.test.tsx b/app/components/showcase/ProjectMedia.test.tsx
new file mode 100644
index 0000000..d2120e0
--- /dev/null
+++ b/app/components/showcase/ProjectMedia.test.tsx
@@ -0,0 +1,177 @@
+import { act, fireEvent, render, screen } from "@testing-library/react";
+import { getFeaturedProjects } from "@/lib/portfolio-data";
+import { ProjectMedia } from "./ProjectMedia";
+import { ShowcaseProvider } from "./ShowcaseProvider";
+
+let reducedMotion = false;
+jest.mock("@/app/hooks/useReducedMotion", () => ({
+  useReducedMotion: () => reducedMotion,
+}));
+jest.mock("./ProjectLightbox", () => ({
+  ProjectLightbox: () => <div role="dialog" aria-label="ampliado" />,
+}));
+
+const projects = getFeaturedProjects(null);
+const nutriscan = projects.find((project) => project.id === "nutriscan");
+if (!nutriscan) throw new Error("projeto ausente");
+
+type Callback = IntersectionObserverCallback;
+const callbacks: Callback[] = [];
+const Original = global.IntersectionObserver;
+
+beforeEach(() => {
+  jest.useFakeTimers();
+  reducedMotion = false;
+  callbacks.length = 0;
+  global.IntersectionObserver = class {
+    constructor(callback: Callback) {
+      callbacks.push(callback);
+    }
+    observe() {}
+    unobserve() {}
+    disconnect() {}
+    takeRecords() {
+      return [];
+    }
+  } as unknown as typeof IntersectionObserver;
+  jest.spyOn(HTMLMediaElement.prototype, "play").mockResolvedValue();
+  jest.spyOn(HTMLMediaElement.prototype, "pause").mockImplementation(() => {});
+  jest.spyOn(HTMLMediaElement.prototype, "load").mockImplementation(() => {});
+});
+
+afterEach(() => {
+  jest.useRealTimers();
+  jest.restoreAllMocks();
+  global.IntersectionObserver = Original;
+});
+
+function renderCard() {
+  const view = render(
+    <ShowcaseProvider projects={projects}>
+      <article className="ds-card">
+        <ProjectMedia project={nutriscan as NonNullable<typeof nutriscan>} />
+      </article>
+    </ShowcaseProvider>,
+  );
+  const frame = view.container.querySelector(".ds-frame") as HTMLElement;
+  frame.getBoundingClientRect = () =>
+    ({
+      top: 300,
+      height: 300,
+      bottom: 600,
+      left: 0,
+      right: 400,
+      width: 400,
+      x: 0,
+      y: 300,
+    }) as DOMRect;
+  return { ...view, frame };
+}
+
+function show(frame: HTMLElement) {
+  act(() => {
+    for (const callback of callbacks)
+      callback(
+        [
+          {
+            target: frame,
+            intersectionRatio: 1,
+            isIntersecting: true,
+          } as unknown as IntersectionObserverEntry,
+        ],
+        {} as IntersectionObserver,
+      );
+    jest.advanceTimersByTime(40);
+  });
+}
+
+describe("ProjectMedia", () => {
+  it("frames the video with the project's address and a button that enlarges it", () => {
+    renderCard();
+
+    expect(screen.getByText("nutriscan.evandro.dev.br")).toBeInTheDocument();
+    const expand = screen.getByRole("button", {
+      name: "Ampliar o vídeo de NutriScan",
+    });
+    expect(expand).toHaveAttribute("aria-haspopup", "dialog");
+    fireEvent.click(expand);
+    expect(
+      screen.getByRole("dialog", { name: "ampliado" }),
+    ).toBeInTheDocument();
+  });
+
+  it("plays only while the card is the active one", () => {
+    const { frame, container } = renderCard();
+    const video = container.querySelector("video") as HTMLVideoElement;
+    expect(container.querySelector(".ds-frame")).toHaveAttribute(
+      "data-active",
+      "false",
+    );
+    expect(video.querySelectorAll("source")).toHaveLength(0);
+
+    show(frame);
+    expect(container.querySelector(".ds-frame")).toHaveAttribute(
+      "data-active",
+      "true",
+    );
+    expect(video.querySelectorAll("source")).toHaveLength(2);
+  });
+
+  it("lets the visitor pause the videos that play on their own, and resume them", () => {
+    const { frame, container } = renderCard();
+    show(frame);
+    expect(container.querySelector(".ds-frame")).toHaveAttribute(
+      "data-active",
+      "true",
+    );
+
+    fireEvent.click(
+      screen.getByRole("button", { name: "Pausar os vídeos dos projetos" }),
+    );
+    act(() => {
+      jest.advanceTimersByTime(40);
+    });
+    expect(container.querySelector(".ds-frame")).toHaveAttribute(
+      "data-active",
+      "false",
+    );
+
+    fireEvent.click(
+      screen.getByRole("button", { name: "Retomar os vídeos dos projetos" }),
+    );
+    act(() => {
+      jest.advanceTimersByTime(40);
+    });
+    expect(container.querySelector(".ds-frame")).toHaveAttribute(
+      "data-active",
+      "true",
+    );
+  });
+
+  it("has no pause button when nothing plays on its own (reduced motion)", () => {
+    reducedMotion = true;
+    renderCard();
+    expect(
+      screen.queryByRole("button", { name: /vídeos dos projetos/ }),
+    ).toBeNull();
+  });
+
+  it("renders nothing for a project without a recorded video", () => {
+    const { container } = render(
+      <ShowcaseProvider projects={projects}>
+        <ProjectMedia project={{ id: "twins-lab", title: "Twins Lab" }} />
+      </ShowcaseProvider>,
+    );
+    expect(container.querySelector(".ds-frame")).toBeNull();
+  });
+
+  it("does nothing, without crashing, when used outside the provider", () => {
+    const { container } = render(
+      <ProjectMedia project={nutriscan as NonNullable<typeof nutriscan>} />,
+    );
+    fireEvent.click(
+      screen.getByRole("button", { name: "Ampliar o vídeo de NutriScan" }),
+    );
+    expect(container.querySelector(".ds-frame")).not.toBeNull();
+  });
+});
diff --git a/app/components/showcase/ProjectMedia.tsx b/app/components/showcase/ProjectMedia.tsx
new file mode 100644
index 0000000..ebeba22
--- /dev/null
+++ b/app/components/showcase/ProjectMedia.tsx
@@ -0,0 +1,79 @@
+"use client";
+
+import type { CSSProperties } from "react";
+import { useReducedMotion } from "@/app/hooks/useReducedMotion";
+import { getProjectVideo, getShowcaseConfig } from "@/lib/project-showcase";
+import { ProjectVideo } from "../ProjectVideo";
+import { BrowserFrame, displayUrl } from "./BrowserFrame";
+import { useShowcaseCard } from "./ShowcaseProvider";
+
+/**
+ * Capa do card com vídeo: o vídeo dentro de uma moldura de navegador, com brilho da cor do site quando é o
+ * card que toca, e o botão que amplia (a tela inteira é o botão).
+ */
+export function ProjectMedia({
+  project,
+}: {
+  project: {
+    id: string;
+    title: string;
+    demoUrl?: string | null;
+    githubUrl?: string | null;
+  };
+}) {
+  const { frameRef, active, open, userPaused, toggleAutoplay } =
+    useShowcaseCard(project.id);
+  const reducedMotion = useReducedMotion();
+  const video = getProjectVideo(project.id);
+  const config = getShowcaseConfig(project.id);
+  if (!video || !config) return null;
+
+  return (
+    <div
+      ref={frameRef}
+      className="ds-frame"
+      data-active={active}
+      style={{ "--accent": config.accent } as CSSProperties}
+    >
+      <BrowserFrame url={displayUrl(project)}>
+        <div
+          className="ds-frame-screen"
+          style={{ backgroundImage: `url(${video.poster})` }}
+        >
+          <ProjectVideo video={video} title={project.title} active={active} />
+          <button
+            type="button"
+            className="ds-frame-expand"
+            onClick={open}
+            aria-haspopup="dialog"
+            aria-label={`Ampliar o vídeo de ${project.title}`}
+          >
+            <span className="ds-frame-chip" aria-hidden="true">
+              Ampliar
+            </span>
+          </button>
+          {!reducedMotion && (
+            <button
+              type="button"
+              className="ds-frame-pause"
+              onClick={toggleAutoplay}
+              aria-label={
+                userPaused
+                  ? "Retomar os vídeos dos projetos"
+                  : "Pausar os vídeos dos projetos"
+              }
+            >
+              <svg viewBox="0 0 16 16" aria-hidden="true">
+                {userPaused ? (
+                  <path d="M4 2.5v11l9-5.5z" />
+                ) : (
+                  <path d="M4 3h3v10H4zM9 3h3v10H9z" />
+                )}
+              </svg>
+            </button>
+          )}
+        </div>
+      </BrowserFrame>
+    </div>
+  );
+}
diff --git a/app/components/showcase/ShowcaseProvider.test.tsx b/app/components/showcase/ShowcaseProvider.test.tsx
new file mode 100644
index 0000000..9e64dec
--- /dev/null
+++ b/app/components/showcase/ShowcaseProvider.test.tsx
@@ -0,0 +1,277 @@
+import { act, fireEvent, render, screen } from "@testing-library/react";
+import { getFeaturedProjects } from "@/lib/portfolio-data";
+import {
+  buildShowcaseItems,
+  ShowcaseProvider,
+  useShowcaseCard,
+} from "./ShowcaseProvider";
+
+let reducedMotion = false;
+jest.mock("@/app/hooks/useReducedMotion", () => ({
+  useReducedMotion: () => reducedMotion,
+}));
+jest.mock("./ProjectLightbox", () => ({
+  ProjectLightbox: ({
+    index,
+    onClose,
+  }: {
+    index: number;
+    onClose: () => void;
+  }) => (
+    <div role="dialog" aria-label="ampliado">
+      aberto:{index}
+      <button type="button" onClick={onClose}>
+        fechar
+      </button>
+    </div>
+  ),
+}));
+
+type FakeObserver = {
+  callback: IntersectionObserverCallback;
+  targets: Set<Element>;
+};
+let observers: FakeObserver[] = [];
+const OriginalObserver = global.IntersectionObserver;
+
+class FakeIntersectionObserver {
+  private readonly state: FakeObserver;
+  constructor(callback: IntersectionObserverCallback) {
+    this.state = { callback, targets: new Set() };
+    observers.push(this.state);
+  }
+  observe(element: Element) {
+    this.state.targets.add(element);
+  }
+  unobserve(element: Element) {
+    this.state.targets.delete(element);
+  }
+  disconnect() {
+    this.state.targets.clear();
+  }
+  takeRecords() {
+    return [];
+  }
+}
+
+function setVisibility(element: Element, ratio: number) {
+  for (const observer of observers) {
+    if (!observer.targets.has(element)) continue;
+    act(() => {
+      observer.callback(
+        [
+          {
+            target: element,
+            intersectionRatio: ratio,
+            isIntersecting: ratio > 0,
+          } as IntersectionObserverEntry,
+        ],
+        observer as unknown as IntersectionObserver,
+      );
+    });
+  }
+}
+
+function place(element: Element, top: number) {
+  element.getBoundingClientRect = () =>
+    ({
+      top,
+      height: 300,
+      bottom: top + 300,
+      left: 0,
+      right: 400,
+      width: 400,
+      x: 0,
+      y: top,
+    }) as DOMRect;
+}
+
+function flush() {
+  act(() => {
+    jest.advanceTimersByTime(40);
+  });
+}
+
+function Card({ id }: { id: string }) {
+  const { frameRef, active, open } = useShowcaseCard(id);
+  return (
+    <article className="ds-card">
+      <div ref={frameRef} data-testid={id} data-active={active} />
+      <button type="button" onClick={open}>
+        ampliar {id}
+      </button>
+    </article>
+  );
+}
+
+const projects = getFeaturedProjects(null);
+
+function setup() {
+  const view = render(
+    <ShowcaseProvider projects={projects}>
+      <Card id="sev-modaintima" />
+      <Card id="lavacao-047" />
+      <Card id="nutriscan" />
+    </ShowcaseProvider>,
+  );
+  const frames = {
+    sev: screen.getByTestId("sev-modaintima"),
+    lavacao: screen.getByTestId("lavacao-047"),
+    nutri: screen.getByTestId("nutriscan"),
+  };
+  // tela de 768px de altura (jsdom): o meio fica em 384
+  place(frames.sev, 100); // centro 250
+  place(frames.lavacao, 230); // centro 380
+  place(frames.nutri, 900); // fora da tela
+  return { view, frames };
+}
+
+beforeEach(() => {
+  jest.useFakeTimers();
+  reducedMotion = false;
+  observers = [];
+  global.IntersectionObserver =
+    FakeIntersectionObserver as unknown as typeof IntersectionObserver;
+});
+
+afterEach(() => {
+  jest.useRealTimers();
+  global.IntersectionObserver = OriginalObserver;
+});
+
+const isActive = (element: Element) =>
+  element.getAttribute("data-active") === "true";
+
+describe("ShowcaseProvider", () => {
+  it("lists only projects that have a recorded showcase, in showcase order", () => {
+    const items = buildShowcaseItems(projects);
+    expect(items.map((item) => item.config.id)).toEqual([
+      "sev-modaintima",
+      "lavacao-047",
+      "nutriscan",
+      "sc-plus",
+      "as-servicos",
+    ]);
+    expect(
+      buildShowcaseItems(projects.filter((p) => p.id === "twins-lab")),
+    ).toEqual([]);
+  });
+
+  it("plays nothing until a card is on screen, then the one closest to the middle", () => {
+    const { frames } = setup();
+    flush();
+    expect(Object.values(frames).some(isActive)).toBe(false);
+
+    setVisibility(frames.sev, 0.8);
+    setVisibility(frames.lavacao, 0.8);
+    flush();
+    expect(isActive(frames.lavacao)).toBe(true);
+    expect(isActive(frames.sev)).toBe(false);
+  });
+
+  it("does not count a card with less than a third on screen", () => {
+    const { frames } = setup();
+    setVisibility(frames.sev, 0.2);
+    setVisibility(frames.lavacao, 0.1);
+    flush();
+    expect(Object.values(frames).some(isActive)).toBe(false);
+  });
+
+  it("hands the video to the card under the mouse and takes it back when the mouse leaves", () => {
+    const { frames } = setup();
+    setVisibility(frames.sev, 0.8);
+    setVisibility(frames.lavacao, 0.8);
+    flush();
+
+    const sevCard = frames.sev.closest(".ds-card") as HTMLElement;
+    fireEvent.pointerEnter(sevCard, { pointerType: "mouse" });
+    flush();
+    expect(isActive(frames.sev)).toBe(true);
+    expect(isActive(frames.lavacao)).toBe(false);
+
+    fireEvent.pointerLeave(sevCard, { pointerType: "mouse" });
+    flush();
+    expect(isActive(frames.lavacao)).toBe(true);
+  });
+
+  it("ignores touch pointers: there is no hover on a phone", () => {
+    const { frames } = setup();
+    setVisibility(frames.sev, 0.8);
+    setVisibility(frames.lavacao, 0.8);
+    flush();
+
+    fireEvent.pointerEnter(frames.sev.closest(".ds-card") as HTMLElement, {
+      pointerType: "touch",
+    });
+    flush();
+    expect(isActive(frames.sev)).toBe(false);
+    expect(isActive(frames.lavacao)).toBe(true);
+  });
+
+  it("follows keyboard focus inside a card", () => {
+    const { frames } = setup();
+    setVisibility(frames.sev, 0.8);
+    setVisibility(frames.lavacao, 0.8);
+    flush();
+
+    fireEvent.focusIn(
+      screen.getByRole("button", { name: "ampliar sev-modaintima" }),
+    );
+    flush();
+    expect(isActive(frames.sev)).toBe(true);
+  });
+
+  it("re-evaluates on scroll", () => {
+    const { frames } = setup();
+    setVisibility(frames.sev, 0.8);
+    setVisibility(frames.lavacao, 0.8);
+    flush();
+    expect(isActive(frames.lavacao)).toBe(true);
+
+    place(frames.sev, 230);
+    place(frames.lavacao, 600);
+    act(() => {
+      window.dispatchEvent(new Event("scroll"));
+    });
+    flush();
+    expect(isActive(frames.sev)).toBe(true);
+  });
+
+  it("pauses every card while the enlarged window is open, and resumes after", () => {
+    const { frames } = setup();
+    setVisibility(frames.lavacao, 0.8);
+    flush();
+    expect(isActive(frames.lavacao)).toBe(true);
+
+    fireEvent.click(
+      screen.getByRole("button", { name: "ampliar lavacao-047" }),
+    );
+    flush();
+    expect(screen.getByRole("dialog", { name: "ampliado" })).toHaveTextContent(
+      "aberto:1",
+    );
+    expect(isActive(frames.lavacao)).toBe(false);
+
+    fireEvent.click(screen.getByRole("button", { name: "fechar" }));
+    flush();
+    expect(screen.queryByRole("dialog")).toBeNull();
+    expect(isActive(frames.lavacao)).toBe(true);
+  });
+
+  it("never plays a card for users who prefer reduced motion", () => {
+    reducedMotion = true;
+    const { frames } = setup();
+    setVisibility(frames.lavacao, 1);
+    flush();
+    expect(isActive(frames.lavacao)).toBe(false);
+  });
+
+  it("stops listening when it unmounts", () => {
+    const { view, frames } = setup();
+    setVisibility(frames.lavacao, 1);
+    view.unmount();
+    expect(observers.every((observer) => observer.targets.size === 0)).toBe(
+      true,
+    );
+  });
+});
diff --git a/app/components/showcase/ShowcaseProvider.tsx b/app/components/showcase/ShowcaseProvider.tsx
new file mode 100644
index 0000000..4c1362b
--- /dev/null
+++ b/app/components/showcase/ShowcaseProvider.tsx
@@ -0,0 +1,251 @@
+"use client";
+
+import {
+  createContext,
+  type ReactNode,
+  useCallback,
+  useContext,
+  useEffect,
+  useMemo,
+  useRef,
+  useState,
+} from "react";
+import { useReducedMotion } from "@/app/hooks/useReducedMotion";
+import type { PortfolioProjectView } from "@/lib/portfolio-data";
+import { SHOWCASE, type ShowcaseConfig } from "@/lib/project-showcase";
+import { ProjectLightbox } from "./ProjectLightbox";
+import { pickActiveCard } from "./showcase-math";
+import "./showcase.css";
+
+export interface ShowcaseItem {
+  config: ShowcaseConfig;
+  project: PortfolioProjectView;
+}
+
+interface ShowcaseApi {
+  register(id: string, element: HTMLElement): () => void;
+  setHover(id: string, hovered: boolean): void;
+  open(id: string): void;
+  /** Pausa (ou retoma) os vídeos que tocam sozinhos nos cards: quem não quer movimento na página tem como desligar. */
+  toggleAutoplay(): void;
+  items: ShowcaseItem[];
+}
+
+interface ActiveState {
+  activeId: string | null;
+  userPaused: boolean;
+}
+
+const ApiContext = createContext<ShowcaseApi | null>(null);
+const ActiveContext = createContext<ActiveState>({
+  activeId: null,
+  userPaused: false,
+});
+
+/** Só aparece como card com vídeo o projeto que existe na lista e tem vídeo gravado. */
+export function buildShowcaseItems(
+  projects: PortfolioProjectView[],
+): ShowcaseItem[] {
+  const items: ShowcaseItem[] = [];
+  for (const config of SHOWCASE) {
+    const project = projects.find((candidate) => candidate.id === config.id);
+    if (project) items.push({ config, project });
+  }
+  return items;
+}
+
+/** Itens da vitrine para quem está dentro do provedor (a vitrine animada usa a mesma lista dos cards). */
+export function useShowcaseItems() {
+  return useContext(ApiContext)?.items ?? [];
+}
+
+/** Abre a janela ampliada de um projeto (nada acontece fora do provedor). */
+export function useShowcaseOpen() {
+  const api = useContext(ApiContext);
+  return useCallback((id: string) => api?.open(id), [api]);
+}
+
+/**
+ * Um vídeo por vez nos cards: toca o card sob o mouse (ou com foco); sem mouse sobre nenhum, o mais perto do
+ * centro da tela. Também guarda qual card está ampliado e mostra a janela ampliada.
+ */
+export function ShowcaseProvider({
+  projects,
+  children,
+}: {
+  projects: PortfolioProjectView[];
+  children: ReactNode;
+}) {
+  const reducedMotion = useReducedMotion();
+  const items = useMemo(() => buildShowcaseItems(projects), [projects]);
+  const [activeId, setActiveId] = useState<string | null>(null);
+  const [openId, setOpenId] = useState<string | null>(null);
+  const [userPaused, setUserPaused] = useState(false);
+
+  const cards = useRef(
+    new Map<string, { el: HTMLElement; visible: boolean }>(),
+  );
+  const hovered = useRef<string | null>(null);
+  const paused = useRef(false);
+  const queued = useRef(false);
+  const frame = useRef(0);
+  const observer = useRef<IntersectionObserver | null>(null);
+
+  const evaluate = useCallback(() => {
+    queued.current = false;
+    if (paused.current || document.hidden) {
+      setActiveId(null);
+      return;
+    }
+    const middle = window.innerHeight / 2;
+    const candidates = [...cards.current].map(([id, { el, visible }]) => {
+      // só quem está à vista entra na disputa: os outros nem têm o layout lido a cada quadro de rolagem
+      if (!visible) return { id, visible, distance: Number.POSITIVE_INFINITY };
+      const rect = el.getBoundingClientRect();
+      return {
+        id,
+        visible,
+        distance: Math.abs(rect.top + rect.height / 2 - middle),
+      };
+    });
+    setActiveId(pickActiveCard(candidates, hovered.current));
+  }, []);
+
+  const schedule = useCallback(() => {
+    if (queued.current) return;
+    queued.current = true;
+    frame.current = requestAnimationFrame(evaluate);
+  }, [evaluate]);
+
+  // com a janela ampliada aberta, ou com preferência por menos movimento, nenhum card toca
+  useEffect(() => {
+    paused.current = reducedMotion || openId !== null || userPaused;
+    schedule();
+  }, [schedule, openId, reducedMotion, userPaused]);
+
+  useEffect(() => {
+    window.addEventListener("scroll", schedule, { passive: true });
+    window.addEventListener("resize", schedule);
+    document.addEventListener("visibilitychange", schedule);
+    return () => {
+      window.removeEventListener("scroll", schedule);
+      window.removeEventListener("resize", schedule);
+      document.removeEventListener("visibilitychange", schedule);
+      cancelAnimationFrame(frame.current);
+      queued.current = false;
+      observer.current?.disconnect();
+      observer.current = null;
+    };
+  }, [schedule]);
+
+  const api = useMemo<ShowcaseApi>(
+    () => ({
+      items,
+      register(id, element) {
+        if (!observer.current && typeof IntersectionObserver !== "undefined") {
+          observer.current = new IntersectionObserver(
+            (entries) => {
+              for (const entry of entries) {
+                for (const card of cards.current.values()) {
+                  // um card só vale como "à vista" com pelo menos um terço dele na tela
+                  if (card.el === entry.target)
+                    card.visible = entry.intersectionRatio >= 0.33;
+                }
+              }
+              schedule();
+            },
+            { threshold: [0, 0.33, 0.66, 1] },
+          );
+        }
+        cards.current.set(id, { el: element, visible: false });
+        observer.current?.observe(element);
+        return () => {
+          observer.current?.unobserve(element);
+          cards.current.delete(id);
+          if (hovered.current === id) hovered.current = null;
+          schedule();
+        };
+      },
+      setHover(id, isHovered) {
+        if (isHovered) hovered.current = id;
+        else if (hovered.current === id) hovered.current = null;
+        schedule();
+      },
+      open(id) {
+        setOpenId(id);
+      },
+      toggleAutoplay() {
+        setUserPaused((paused) => !paused);
+      },
+    }),
+    [items, schedule],
+  );
+
+  const activeState = useMemo(
+    () => ({ activeId, userPaused }),
+    [activeId, userPaused],
+  );
+
+  const openIndex = openId
+    ? items.findIndex((item) => item.config.id === openId)
+    : -1;
+
+  return (
+    <ApiContext.Provider value={api}>
+      <ActiveContext.Provider value={activeState}>
+        {children}
+        {openIndex >= 0 && (
+          <ProjectLightbox
+            items={items}
+            index={openIndex}
+            onClose={() => setOpenId(null)}
+            onNavigate={(index) => setOpenId(items[index]?.config.id ?? null)}
+          />
+        )}
+      </ActiveContext.Provider>
+    </ApiContext.Provider>
+  );
+}
+
+/** Liga um card à vitrine: devolve a ref da moldura, se ele é o card que toca agora e como ampliá-lo. */
+export function useShowcaseCard(id: string) {
+  const api = useContext(ApiContext);
+  const { activeId, userPaused } = useContext(ActiveContext);
+  const frameRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    const element = frameRef.current;
+    if (!api || !element) return;
+    const unregister = api.register(id, element);
+    const card = element.closest<HTMLElement>(".ds-card") ?? element;
+    const enter = (event: PointerEvent) => {
+      // no toque não existe "passar o mouse": só o mouse e a caneta mandam na vitrine
+      if (event.pointerType !== "touch") api.setHover(id, true);
+    };
+    const leave = () => api.setHover(id, false);
+    const focusIn = () => api.setHover(id, true);
+    const focusOut = (event: FocusEvent) => {
+      if (!card.contains(event.relatedTarget as Node | null))
+        api.setHover(id, false);
+    };
+    card.addEventListener("pointerenter", enter);
+    card.addEventListener("pointerleave", leave);
+    card.addEventListener("focusin", focusIn);
+    card.addEventListener("focusout", focusOut);
+    return () => {
+      unregister();
+      card.removeEventListener("pointerenter", enter);
+      card.removeEventListener("pointerleave", leave);
+      card.removeEventListener("focusin", focusIn);
+      card.removeEventListener("focusout", focusOut);
+    };
+  }, [api, id]);
+
+  return {
+    frameRef,
+    active: activeId === id,
+    userPaused,
+    toggleAutoplay: useCallback(() => api?.toggleAutoplay(), [api]),
+    open: useCallback(() => api?.open(id), [api, id]),
+  };
+}
diff --git a/app/components/showcase/showcase-math.test.ts b/app/components/showcase/showcase-math.test.ts
new file mode 100644
index 0000000..55d2673
--- /dev/null
+++ b/app/components/showcase/showcase-math.test.ts
@@ -0,0 +1,104 @@
+import {
+  easeToward,
+  locateInReel,
+  pickActiveCard,
+  reelStarts,
+  videoProgress,
+} from "./showcase-math";
+
+const card = (id: string, visible: boolean, distance: number) => ({
+  id,
+  visible,
+  distance,
+});
+
+describe("pickActiveCard", () => {
+  it("plays the visible card closest to the middle of the screen", () => {
+    expect(
+      pickActiveCard(
+        [card("a", true, 300), card("b", true, 80), card("c", false, 5)],
+        null,
+      ),
+    ).toBe("b");
+  });
+
+  it("lets the hovered card win over a closer one, but only while it is visible", () => {
+    const cards = [card("a", true, 10), card("b", true, 400)];
+    expect(pickActiveCard(cards, "b")).toBe("b");
+    expect(
+      pickActiveCard([card("a", true, 10), card("b", false, 0)], "b"),
+    ).toBe("a");
+  });
+
+  it("keeps the first card on a tie, so the left one of a row wins", () => {
+    expect(
+      pickActiveCard(
+        [card("left", true, 120), card("right", true, 120.3)],
+        null,
+      ),
+    ).toBe("left");
+  });
+
+  it("plays nothing when no card is on screen", () => {
+    expect(pickActiveCard([card("a", false, 0)], null)).toBeNull();
+    expect(pickActiveCard([], null)).toBeNull();
+  });
+});
+
+describe("locateInReel", () => {
+  const weights = [1, 2, 1];
+
+  it("maps overall progress to a project and a position inside it", () => {
+    expect(locateInReel(weights, 0)).toEqual({ index: 0, local: 0 });
+    expect(locateInReel(weights, 0.125)).toEqual({ index: 0, local: 0.5 });
+    const middle = locateInReel(weights, 0.5);
+    expect(middle.index).toBe(1);
+    expect(middle.local).toBeCloseTo(0.5);
+    expect(locateInReel(weights, 1)).toEqual({ index: 2, local: 1 });
+  });
+
+  it("clamps progress outside the pinned range", () => {
+    expect(locateInReel(weights, -3)).toEqual({ index: 0, local: 0 });
+    expect(locateInReel(weights, 7)).toEqual({ index: 2, local: 1 });
+  });
+
+  it("copes with an empty reel", () => {
+    expect(locateInReel([], 0.4)).toEqual({ index: 0, local: 0 });
+  });
+
+  it("gives each project the share of the scroll that its weight asks for", () => {
+    expect(reelStarts(weights)).toEqual([0, 0.25, 0.75]);
+  });
+});
+
+describe("videoProgress", () => {
+  it("holds still at the start and at the end of each project's stretch", () => {
+    expect(videoProgress(0)).toBe(0);
+    expect(videoProgress(0.1)).toBe(0);
+    expect(videoProgress(0.5)).toBeCloseTo(0.5);
+    expect(videoProgress(0.9)).toBe(1);
+    expect(videoProgress(1)).toBe(1);
+  });
+});
+
+describe("easeToward", () => {
+  it("moves toward the target and never overshoots", () => {
+    const first = easeToward(0, 1, 1 / 60);
+    expect(first).toBeGreaterThan(0);
+    expect(first).toBeLessThan(1);
+    expect(easeToward(0.5, 0.5, 1)).toBe(0.5);
+    expect(easeToward(0, 1, 10)).toBeCloseTo(1, 5);
+  });
+
+  it("does not depend on the frame rate", () => {
+    let sixty = 0;
+    for (let i = 0; i < 60; i += 1) sixty = easeToward(sixty, 1, 1 / 60);
+    let thirty = 0;
+    for (let i = 0; i < 30; i += 1) thirty = easeToward(thirty, 1, 1 / 30);
+    expect(sixty).toBeCloseTo(thirty, 6);
+  });
+
+  it("stands still when no time has passed", () => {
+    expect(easeToward(0.2, 1, 0)).toBe(0.2);
+  });
+});
diff --git a/app/components/showcase/showcase-math.ts b/app/components/showcase/showcase-math.ts
new file mode 100644
index 0000000..3cd82d8
--- /dev/null
+++ b/app/components/showcase/showcase-math.ts
@@ -0,0 +1,91 @@
+/** Contas puras da vitrine (sem DOM), separadas para serem testadas uma a uma. */
+
+export interface CardCandidate {
+  id: string;
+  visible: boolean;
+  /** Distância do centro do card ao centro da tela, em pixels. */
+  distance: number;
+}
+
+/**
+ * Qual card toca: o que está sob o mouse (se visível); senão o visível mais perto do centro da tela.
+ * Empate fica com o primeiro da lista (ordem do DOM: esquerda antes de direita).
+ */
+export function pickActiveCard(
+  candidates: CardCandidate[],
+  hoveredId: string | null,
+): string | null {
+  const visible = candidates.filter((candidate) => candidate.visible);
+  if (hoveredId && visible.some((candidate) => candidate.id === hoveredId))
+    return hoveredId;
+  let best: CardCandidate | null = null;
+  for (const candidate of visible) {
+    if (!best || candidate.distance < best.distance - 0.5) best = candidate;
+  }
+  return best?.id ?? null;
+}
+
+export interface ReelPosition {
+  /** Projeto em cena. */
+  index: number;
+  /** Quanto do trecho do projeto já passou (0 a 1). */
+  local: number;
+}
+
+/** Em que projeto e em que ponto dele a rolagem está, dado o avanço total `t` (0 a 1) e o peso de cada trecho. */
+export function locateInReel(weights: number[], t: number): ReelPosition {
+  const total = weights.reduce((sum, weight) => sum + weight, 0);
+  if (weights.length === 0 || total <= 0) return { index: 0, local: 0 };
+  const position = Math.min(1, Math.max(0, t)) * total;
+  let start = 0;
+  for (let index = 0; index < weights.length; index += 1) {
+    const end = start + weights[index];
+    if (position < end || index === weights.length - 1) {
+      const local = (position - start) / weights[index];
+      return { index, local: Math.min(1, Math.max(0, local)) };
+    }
+    start = end;
+  }
+  return { index: weights.length - 1, local: 1 };
+}
+
+/** Início do trecho de cada projeto, como fração (0 a 1) do avanço total. */
+export function reelStarts(weights: number[]): number[] {
+  const total = weights.reduce((sum, weight) => sum + weight, 0);
+  let acc = 0;
+  return weights.map((weight) => {
+    const start = total > 0 ? acc / total : 0;
+    acc += weight;
+    return start;
+  });
+}
+
+/** Fração do trecho de cada projeto em que o vídeo fica parado, no começo e no fim. */
+export const REEL_HOLD = 0.1;
+
+/** Avanço total (0 a 1) em que o projeto `index` está em `local` (0 a 1) do trecho dele. */
+export function reelOffset(weights: number[], index: number, local: number) {
+  const total = weights.reduce((sum, weight) => sum + weight, 0);
+  if (total <= 0 || index < 0 || index >= weights.length) return 0;
+  return reelStarts(weights)[index] + (local * weights[index]) / total;
+}
+
+/**
+ * O trecho de cada projeto tem uma pausa no começo e outra no fim: o vídeo só anda no meio.
+ * Isso dá tempo de ler o título antes de o site começar a rolar e de descansar antes da troca.
+ */
+export function videoProgress(local: number, hold = REEL_HOLD): number {
+  const span = 1 - hold * 2;
+  return Math.min(1, Math.max(0, (local - hold) / span));
+}
+
+/** Aproxima `current` de `target` de forma suave, independente da taxa de quadros (`tau` em segundos). */
+export function easeToward(
+  current: number,
+  target: number,
+  deltaSeconds: number,
+  tau = 0.07,
+): number {
+  const factor = 1 - Math.exp(-Math.max(0, deltaSeconds) / tau);
+  return current + (target - current) * factor;
+}
diff --git a/app/components/showcase/showcase.css b/app/components/showcase/showcase.css
new file mode 100644
index 0000000..75920f4
--- /dev/null
+++ b/app/components/showcase/showcase.css
@@ -0,0 +1,1238 @@
+/*
+ * Vitrine dos projetos: moldura de navegador, capa dos cards, celular, vitrine animada (.ds-reel) e vídeo
+ * ampliado (.ds-lb). Tudo pensado para a seção escura de Projetos: cantos retos, rótulos em mono, lima como
+ * única cor de ação e a cor do site de cada projeto (--accent) só no brilho ao redor do vídeo.
+ */
+
+/* ─────────────────────────── Moldura de navegador ─────────────────────────── */
+
+.ds-bframe {
+  display: flex;
+  flex-direction: column;
+  min-width: 0;
+  border: 1px solid rgba(255, 255, 255, 0.12);
+  background: #0b0b0b;
+  box-shadow: 0 28px 60px -34px rgba(0, 0, 0, 0.9);
+}
+
+.ds-bframe-bar {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  flex: none;
+  height: 30px;
+  padding: 0 10px;
+  background: #141414;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
+}
+
+.ds-bframe-dots {
+  display: flex;
+  flex: none;
+  gap: 6px;
+
+  & i {
+    width: 7px;
+    height: 7px;
+    border-radius: 50%;
+    background: rgba(255, 255, 255, 0.2);
+  }
+}
+
+.ds-bframe-url {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  flex: 1 1 auto;
+  min-width: 0;
+  max-width: 360px;
+  height: 20px;
+  margin-inline: auto;
+  padding: 0 9px;
+  font-family: var(--font-mono);
+  font-size: 10px;
+  letter-spacing: 0.04em;
+  color: rgba(255, 255, 255, 0.6);
+  background: rgba(255, 255, 255, 0.05);
+  border: 1px solid rgba(255, 255, 255, 0.08);
+
+  & svg {
+    flex: none;
+    opacity: 0.7;
+  }
+
+  & span {
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+}
+
+@media (max-width: 479px) {
+  .ds-bframe-bar {
+    height: 26px;
+    gap: 8px;
+    padding: 0 8px;
+  }
+
+  .ds-bframe-dots i {
+    width: 6px;
+    height: 6px;
+  }
+
+  .ds-bframe-url {
+    height: 18px;
+    font-size: 9px;
+  }
+}
+
+/* ─────────────────────────── Capa dos cards ─────────────────────────── */
+
+.ds-frame {
+  --accent: var(--slash);
+  position: relative;
+  isolation: isolate;
+  flex: none; /* o card é uma coluna flex: sem isto a capa encolhe e perde a proporção */
+  margin-bottom: var(--sp-5);
+
+  /* brilho na cor do site, só no card que está tocando */
+  &::after {
+    content: "";
+    position: absolute;
+    z-index: -1;
+    inset: 4% 6% 4%;
+    background: radial-gradient(
+      60% 70% at 50% 50%,
+      color-mix(in srgb, var(--accent) 45%, transparent),
+      transparent 72%
+    );
+    filter: blur(32px);
+    opacity: 0;
+    transition: opacity 0.7s var(--ease-out);
+    pointer-events: none;
+  }
+
+  &[data-active="true"]::after {
+    opacity: 0.5;
+  }
+}
+
+.ds-frame-screen {
+  position: relative;
+  aspect-ratio: 16 / 10;
+  overflow: hidden;
+  background: #0a0a0a center top / cover no-repeat;
+
+  & > video,
+  & > img {
+    position: absolute;
+    inset: 0;
+    width: 100%;
+    height: 100%;
+    object-fit: cover;
+    object-position: top;
+    transform-origin: top center;
+    transition:
+      transform 0.7s var(--ease-out),
+      opacity 0.6s ease;
+  }
+
+  /* o poster já está de fundo: o vídeo entra em fade quando começa a tocar */
+  & > video {
+    opacity: 0;
+  }
+
+  & > video[data-ready="true"] {
+    opacity: 1;
+  }
+}
+
+@media (hover: hover) {
+  .ds-card:hover .ds-frame-screen > video,
+  .ds-card:hover .ds-frame-screen > img {
+    transform: scale(1.02);
+  }
+}
+
+.ds-frame-expand {
+  position: absolute;
+  inset: 0;
+  padding: 0;
+  border: 0;
+  background: transparent;
+  cursor: zoom-in;
+
+  &:focus-visible {
+    outline: 2px solid var(--slash);
+    outline-offset: -4px;
+  }
+}
+
+.ds-frame-chip {
+  position: absolute;
+  right: 10px;
+  bottom: 10px;
+  display: inline-flex;
+  align-items: center;
+  gap: 6px;
+  min-height: 28px;
+  padding: 0 10px;
+  font-family: var(--font-mono);
+  font-size: 10px;
+  letter-spacing: 0.1em;
+  text-transform: uppercase;
+  color: var(--ink);
+  background: var(--slash);
+  opacity: 0;
+  transform: translateY(6px);
+  transition:
+    opacity 0.25s ease,
+    transform 0.25s var(--ease-out);
+  pointer-events: none;
+
+  &::after {
+    content: "↗";
+  }
+}
+
+.ds-frame-expand:hover .ds-frame-chip,
+.ds-frame-expand:focus-visible .ds-frame-chip {
+  opacity: 1;
+  transform: none;
+}
+
+/* pausa dos vídeos que tocam sozinhos (WCAG 2.2.2): alvo de toque de 44px, ícone de 28px */
+.ds-frame-pause {
+  position: absolute;
+  left: 2px;
+  bottom: 2px;
+  display: grid;
+  place-items: center;
+  width: 44px;
+  height: 44px;
+  padding: 0;
+  border: 0;
+  color: #fff;
+  background: transparent;
+  cursor: pointer;
+
+  & svg {
+    width: 28px;
+    height: 28px;
+    padding: 7px;
+    fill: currentColor;
+    background: rgba(5, 5, 5, 0.66);
+    border: 1px solid rgba(255, 255, 255, 0.22);
+    transition: background 0.2s ease;
+  }
+
+  &:hover svg {
+    background: rgba(5, 5, 5, 0.9);
+  }
+
+  &:focus-visible {
+    outline: 2px solid var(--slash);
+    outline-offset: -4px;
+  }
+}
+
+/* sem mouse não existe "passar por cima": o aviso fica sempre à vista */
+@media (hover: none) {
+  .ds-frame-chip {
+    opacity: 1;
+    transform: none;
+  }
+}
+
+/* ─────────────────────────── Celular ─────────────────────────── */
+
+.ds-phone {
+  position: relative;
+  flex: none;
+  aspect-ratio: 390 / 844;
+  padding: 7px;
+  background: #111;
+  border: 1px solid rgba(255, 255, 255, 0.16);
+  border-radius: 30px;
+  box-shadow:
+    0 30px 60px -28px rgba(0, 0, 0, 0.9),
+    inset 0 0 0 1px rgba(255, 255, 255, 0.05);
+
+  &::before {
+    content: "";
+    position: absolute;
+    z-index: 2;
+    top: 11px;
+    left: 50%;
+    width: 24%;
+    height: 4px;
+    transform: translateX(-50%);
+    border-radius: 4px;
+    background: #000;
+    opacity: 0.8;
+  }
+}
+
+.ds-phone-screen {
+  position: relative;
+  width: 100%;
+  height: 100%;
+  overflow: hidden;
+  border-radius: 24px;
+  background: #0a0a0a center top / cover no-repeat;
+
+  & > video {
+    position: absolute;
+    inset: 0;
+    display: block;
+    width: 100%;
+    height: 100%;
+    object-fit: cover;
+    object-position: top;
+  }
+}
+
+/* ─────────────────────────── Vitrine animada ─────────────────────────── */
+
+.ds-reel {
+  --pin-h: calc(100svh - var(--site-header-height));
+  position: relative;
+  margin-top: var(--sp-16);
+  /* a cena fica presa durante (soma dos pesos) alturas de tela de rolagem */
+  height: calc(var(--pin-h) + var(--reel-sum, 1) * 100svh);
+}
+
+.ds-reel-pin {
+  position: sticky;
+  top: var(--site-header-height);
+  height: var(--pin-h);
+  overflow: clip;
+}
+
+.ds-reel-grid {
+  display: grid;
+  grid-template-columns: minmax(0, 1fr);
+  grid-template-rows: auto minmax(0, 1fr);
+  gap: var(--sp-4);
+  height: 100%;
+  padding-block: var(--sp-4);
+}
+
+@media (min-width: 1024px) {
+  .ds-reel-grid {
+    grid-template-columns: minmax(190px, 250px) minmax(0, 1fr);
+    grid-template-rows: minmax(0, 1fr);
+    gap: var(--sp-10);
+    padding-block: var(--sp-6);
+  }
+}
+
+/* lista de projetos: faixa rolável na horizontal em telas pequenas, coluna no desktop */
+.ds-reel-index {
+  min-width: 0;
+
+  & > ol {
+    display: flex;
+    gap: 8px;
+    list-style: none;
+    overflow-x: auto;
+    scrollbar-width: none;
+  }
+
+  & > ol::-webkit-scrollbar {
+    display: none;
+  }
+
+  & > ol > li > button {
+    position: relative;
+    display: flex;
+    align-items: center;
+    gap: 10px;
+    min-height: 44px;
+    padding: 0 14px;
+    font-family: var(--font-mono);
+    font-size: 11px;
+    letter-spacing: 0.06em;
+    white-space: nowrap;
+    color: rgba(255, 255, 255, 0.66);
+    background: rgba(255, 255, 255, 0.03);
+    border: 1px solid rgba(255, 255, 255, 0.12);
+    cursor: pointer;
+    transition:
+      color 0.25s ease,
+      border-color 0.25s ease,
+      background 0.25s ease;
+
+    @media (hover: hover) {
+      &:hover {
+        color: #fff;
+        border-color: rgba(255, 255, 255, 0.3);
+      }
+    }
+
+    /* por dentro: a faixa rolável (overflow-x) cortaria o anel desenhado para fora */
+    &:focus-visible {
+      outline: 2px solid var(--slash);
+      outline-offset: -4px;
+    }
+
+    &[aria-current="true"] {
+      color: #fff;
+      border-color: rgba(204, 255, 0, 0.55);
+      background: rgba(204, 255, 0, 0.07);
+    }
+  }
+}
+
+.ds-reel-hint {
+  display: none;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: 6px 10px;
+  margin-bottom: var(--sp-5);
+  font-family: var(--font-mono);
+  font-size: 10px;
+  letter-spacing: 0.14em;
+  text-transform: uppercase;
+  color: var(--slash);
+}
+
+.ds-reel-hint-line {
+  width: 24px;
+  height: 1px;
+  background: var(--slash);
+}
+
+.ds-reel-hint-sub {
+  width: 100%;
+  color: rgba(255, 255, 255, 0.5);
+}
+
+.ds-reel-num {
+  color: var(--slash);
+}
+
+.ds-reel-name {
+  display: none;
+}
+
+/* trechos do projeto em cena: só no desktop, onde sobra coluna; cada um leva ao ponto do vídeo */
+.ds-reel-chapters {
+  display: none;
+  list-style: none;
+  margin: 6px 0 10px 16px;
+  border-left: 1px solid rgba(255, 255, 255, 0.12);
+
+  & button {
+    display: flex;
+    align-items: center;
+    width: 100%;
+    min-height: 32px;
+    gap: 10px;
+    padding: 0 12px;
+    border: 0;
+    background: transparent;
+    font-size: 10px;
+    letter-spacing: 0.08em;
+    text-transform: uppercase;
+    color: rgba(255, 255, 255, 0.55);
+    text-align: left;
+
+    & span {
+      color: rgba(255, 255, 255, 0.5);
+    }
+
+    @media (hover: hover) {
+      &:hover {
+        color: #fff;
+      }
+    }
+
+    &[aria-current="true"] {
+      color: var(--slash);
+      background: transparent;
+      border: 0;
+
+      & span {
+        color: var(--slash);
+      }
+    }
+  }
+}
+
+@media (min-width: 1024px) {
+  .ds-reel-chapters {
+    display: grid;
+  }
+}
+
+@media (min-width: 1024px) and (pointer: coarse) {
+  .ds-reel-chapters button {
+    min-height: 44px;
+  }
+}
+
+.ds-reel-bar {
+  position: absolute;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  height: 2px;
+  background: var(--slash);
+  transform: scaleX(var(--p, 0));
+  transform-origin: left;
+  opacity: 0;
+}
+
+.ds-reel-index > ol > li > button[aria-current="true"] .ds-reel-bar {
+  opacity: 1;
+}
+
+@media (min-width: 640px) {
+  .ds-reel-name {
+    display: inline;
+  }
+}
+
+@media (min-width: 1024px) {
+  .ds-reel-hint {
+    display: flex;
+  }
+
+  .ds-reel-index > ol {
+    flex-direction: column;
+    gap: 6px;
+    overflow: visible;
+  }
+
+  .ds-reel-index > ol > li > button {
+    width: 100%;
+    gap: 14px;
+    padding: 0 16px;
+  }
+}
+
+.ds-reel-stage {
+  position: relative;
+  min-height: 0;
+  /* o palco mede a si mesmo: o conjunto cresce até o limite da largura ou da altura que sobrar */
+  container-type: size;
+}
+
+.ds-reel-layer {
+  --accent: var(--slash);
+  position: absolute;
+  inset: 0;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  opacity: 0;
+  visibility: hidden;
+  transform: translateY(14px);
+  transition:
+    opacity 0.5s ease,
+    transform 0.6s var(--ease-out),
+    visibility 0s linear 0.5s;
+
+  &[data-state="before"] {
+    transform: translateY(-14px);
+  }
+
+  &[data-state="active"] {
+    opacity: 1;
+    visibility: visible;
+    transform: none;
+    transition-delay: 0s;
+  }
+}
+
+/* aparelhos + legenda, um bloco só: a legenda tem sempre a mesma largura e o mesmo canto esquerdo do notebook */
+.ds-reel-set {
+  --caption-h: 13.75rem; /* reserva da legenda: título, trecho atual e botões */
+  --gap: var(--sp-6);
+  display: flex;
+  flex-direction: column;
+  gap: var(--gap);
+  /* cabe na largura (com folga para o celular sobrepor) e na altura (legenda + barra de 30px + tela 16:10) */
+  width: min(90cqw, calc((100cqh - var(--caption-h) - var(--gap) - 30px) * 1.6));
+  min-width: min(100%, 320px);
+}
+
+.ds-reel-devices {
+  position: relative;
+
+  &::before {
+    content: "";
+    position: absolute;
+    inset: -4% 0;
+    z-index: -1;
+    background: radial-gradient(
+      55% 60% at 50% 50%,
+      color-mix(in srgb, var(--accent) 42%, transparent),
+      transparent 72%
+    );
+    filter: blur(44px);
+    opacity: 0.45;
+    pointer-events: none;
+  }
+}
+
+.ds-reel-set {
+  isolation: isolate;
+}
+
+.ds-reel-laptop {
+  width: 100%;
+}
+
+.ds-reel-screen {
+  position: relative;
+  aspect-ratio: 16 / 10;
+  overflow: hidden;
+  background: #0a0a0a center top / cover no-repeat;
+
+  & > video {
+    position: absolute;
+    inset: 0;
+    display: block;
+    width: 100%;
+    height: 100%;
+    object-fit: cover;
+    object-position: top;
+  }
+}
+
+.ds-reel-phone {
+  position: absolute;
+  right: -5%;
+  bottom: -3%;
+  width: 22%;
+  min-width: 88px;
+}
+
+/* celular: o celular é o aparelho principal (o notebook some) e a legenda ocupa a largura toda */
+@media (max-width: 639px) {
+  .ds-reel-grid {
+    /* respiro para o botão fixo de preferências de analytics, que ocupa o canto de baixo */
+    padding-bottom: 68px;
+  }
+
+  .ds-reel-layer {
+    align-items: stretch;
+  }
+
+  .ds-reel-set {
+    --caption-h: 12.5rem;
+    width: min(100cqw, 460px);
+    height: 100%;
+    margin-inline: auto;
+    justify-content: space-between;
+  }
+
+  .ds-reel-devices {
+    flex: 1 1 0;
+    min-height: 0;
+    display: flex;
+    justify-content: center;
+  }
+
+  .ds-reel-laptop {
+    display: none;
+  }
+
+  .ds-reel-phone {
+    position: relative;
+    inset: auto;
+    width: auto;
+    min-width: 0;
+    height: 100%;
+    max-width: 100%;
+  }
+}
+
+.ds-reel-caption {
+  flex: none;
+  display: grid;
+  gap: 6px;
+  min-width: 0;
+}
+
+.ds-reel-title {
+  font-family: var(--font-display);
+  font-size: clamp(22px, 3vw, 38px);
+  font-weight: 800;
+  line-height: 1.02;
+  letter-spacing: -0.03em;
+  color: #fff;
+}
+
+.ds-reel-sub {
+  font-size: 14px;
+  line-height: 1.5;
+  color: rgba(255, 255, 255, 0.68);
+  display: -webkit-box;
+  -webkit-line-clamp: 2;
+  -webkit-box-orient: vertical;
+  overflow: hidden;
+}
+
+.ds-reel-chapter {
+  display: flex;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: 6px 12px;
+  margin-top: 4px;
+  font-size: 13px;
+  color: #fff;
+
+  & strong {
+    font-weight: 600;
+  }
+}
+
+.ds-reel-chapter-count {
+  font-family: var(--font-mono);
+  font-size: 11px;
+  letter-spacing: 0.08em;
+  color: var(--slash);
+}
+
+.ds-reel-ticks {
+  display: flex;
+  gap: 4px;
+  list-style: none;
+
+  & li {
+    width: 18px;
+    height: 3px;
+    background: rgba(255, 255, 255, 0.18);
+    transition: background 0.3s ease;
+  }
+
+  & li[data-state="done"] {
+    background: rgba(204, 255, 0, 0.5);
+  }
+
+  & li[data-state="now"] {
+    background: var(--slash);
+  }
+}
+
+.ds-reel-actions {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--sp-3);
+  margin-top: var(--sp-2);
+}
+
+.ds-reel-actions .ds-link-muted {
+  border-color: rgba(255, 255, 255, 0.18);
+  color: #fff;
+}
+
+/* tela baixa (celular deitado, janela de desktop curta): a vitrine não cabe, e os cards já mostram os vídeos */
+@media (max-height: 560px) {
+  .ds-reel {
+    display: none;
+  }
+}
+
+/* desktop com pouca altura: a lista de projetos e os trechos têm de caber na altura do pin */
+@media (min-width: 1024px) and (max-height: 700px) {
+  .ds-reel-hint {
+    display: none;
+  }
+}
+
+@media (min-width: 1024px) and (max-height: 700px) and (pointer: fine) {
+  .ds-reel-index > ol > li > button {
+    min-height: 38px;
+  }
+
+  .ds-reel-chapters button {
+    min-height: 28px;
+  }
+}
+
+/* janela curta: sem o subtítulo a legenda cabe em menos altura e o notebook ganha tela */
+@media (min-width: 640px) and (max-height: 700px) {
+  .ds-reel-set {
+    --caption-h: 10.5rem;
+  }
+
+  .ds-reel-sub {
+    display: none;
+  }
+}
+
+/* celular: o subtítulo sai para o aparelho ter mais tela, e o contador "02/05" já faz o papel dos tiques */
+@media (max-width: 639px) {
+  .ds-reel-sub,
+  .ds-reel-ticks {
+    display: none;
+  }
+}
+
+/* celular baixo demais: o aparelho ficaria uma cápsula ilegível */
+@media (max-width: 639px) and (max-height: 600px) {
+  .ds-reel {
+    display: none;
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .ds-reel {
+    display: none;
+  }
+}
+
+/* sem JavaScript a vitrine nunca monta: o espaço reservado por ela some */
+@media (scripting: none) {
+  .ds-reel-placeholder {
+    display: none;
+  }
+}
+
+/* ─────────────────────────── Vídeo ampliado ─────────────────────────── */
+
+html.ds-lb-open {
+  overflow: hidden;
+  /* a barra de rolagem clássica some junto: devolve o espaço dela para a página não pular */
+  padding-right: var(--ds-scrollbar, 0px);
+}
+
+.ds-lb {
+  --accent: var(--slash);
+  color-scheme: dark;
+  position: fixed;
+  inset: 0;
+  width: 100%;
+  height: 100%;
+  max-width: none;
+  max-height: none;
+  margin: 0;
+  padding: clamp(12px, 3vw, 32px);
+  border: 0;
+  color: #fff;
+  background: rgba(5, 5, 5, 0.88);
+  backdrop-filter: blur(8px);
+  overscroll-behavior: contain;
+
+  &[open] {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    animation: ds-lb-in 0.28s var(--ease-out);
+  }
+
+  &::backdrop {
+    background: transparent;
+  }
+}
+
+@keyframes ds-lb-in {
+  from {
+    opacity: 0;
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .ds-lb[open] {
+    animation: none;
+  }
+}
+
+.ds-lb-panel {
+  display: flex;
+  flex-direction: column;
+  gap: var(--sp-4);
+  width: min(1180px, 100%);
+  height: min(100%, 900px);
+  min-height: 0;
+  padding: clamp(14px, 2.4vw, 24px);
+  overflow: auto;
+  background: #0c0c0c;
+  border: 1px solid rgba(255, 255, 255, 0.12);
+  box-shadow: 0 0 120px -30px color-mix(in srgb, var(--accent) 55%, transparent);
+}
+
+.ds-lb-head {
+  display: flex;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: var(--sp-3) var(--sp-4);
+}
+
+.ds-lb-heading {
+  flex: 1 1 200px;
+  min-width: 0;
+}
+
+.ds-lb-count {
+  font-family: var(--font-mono);
+  font-size: 10px;
+  letter-spacing: 0.14em;
+  color: var(--slash);
+}
+
+.ds-lb-title {
+  font-family: var(--font-display);
+  font-size: clamp(20px, 2.6vw, 30px);
+  font-weight: 800;
+  line-height: 1.05;
+  letter-spacing: -0.03em;
+}
+
+.ds-lb-toggle {
+  display: inline-flex;
+  min-width: 0;
+  margin: 0;
+  padding: 0;
+  border: 1px solid rgba(255, 255, 255, 0.16);
+
+  & button {
+    min-height: 44px;
+    padding: 0 16px;
+    font-family: var(--font-mono);
+    font-size: 11px;
+    letter-spacing: 0.08em;
+    text-transform: uppercase;
+    color: rgba(255, 255, 255, 0.7);
+    background: transparent;
+    border: 0;
+    cursor: pointer;
+    transition:
+      background 0.2s ease,
+      color 0.2s ease;
+
+    &[aria-pressed="true"] {
+      color: var(--ink);
+      background: var(--slash);
+    }
+
+    &:focus-visible {
+      outline: 2px solid var(--slash);
+      outline-offset: -3px;
+    }
+  }
+}
+
+.ds-lb-nav {
+  display: flex;
+  gap: 6px;
+
+  & button {
+    display: grid;
+    place-items: center;
+    width: 44px;
+    height: 44px;
+    padding: 0;
+    color: #fff;
+    background: transparent;
+    border: 1px solid rgba(255, 255, 255, 0.16);
+    cursor: pointer;
+    transition: border-color 0.2s ease;
+
+    @media (hover: hover) {
+      &:hover:not(:disabled) {
+        border-color: rgba(255, 255, 255, 0.5);
+      }
+    }
+
+    &:disabled {
+      opacity: 0.3;
+      cursor: default;
+    }
+
+    &:focus-visible {
+      outline: 2px solid var(--slash);
+      outline-offset: 2px;
+    }
+
+    & svg {
+      width: 16px;
+      height: 16px;
+      fill: none;
+      stroke: currentColor;
+      stroke-width: 1.6;
+    }
+  }
+}
+
+/* o palco mede a si mesmo: o aparelho cresce até o limite da largura ou da altura que sobrar */
+.ds-lb-stage {
+  flex: 1 1 0;
+  min-height: 200px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  container-type: size;
+}
+
+.ds-lb-frame {
+  width: min(100cqw, calc((100cqh - 30px) * 1.6));
+}
+
+.ds-lb-screen {
+  position: relative;
+  aspect-ratio: 16 / 10;
+  overflow: hidden;
+  background: #0a0a0a center top / cover no-repeat;
+}
+
+.ds-lb-video {
+  position: absolute;
+  inset: 0;
+  display: block;
+  width: 100%;
+  height: 100%;
+  object-fit: cover;
+  object-position: top;
+}
+
+.ds-lb-phone {
+  height: min(100cqh, calc(100cqw * 844 / 390));
+}
+
+.ds-lb-controls {
+  display: flex;
+  align-items: center;
+  gap: var(--sp-3);
+}
+
+.ds-lb-play {
+  display: grid;
+  flex: none;
+  place-items: center;
+  width: 44px;
+  height: 44px;
+  padding: 0;
+  color: var(--ink);
+  background: var(--slash);
+  border: 0;
+  cursor: pointer;
+
+  &:focus-visible {
+    outline: 2px solid #fff;
+    outline-offset: 2px;
+  }
+
+  & svg {
+    width: 16px;
+    height: 16px;
+    fill: currentColor;
+  }
+}
+
+.ds-lb-time {
+  flex: none;
+  min-width: 72px;
+  font-family: var(--font-mono);
+  font-size: 11px;
+  font-variant-numeric: tabular-nums;
+  color: rgba(255, 255, 255, 0.7);
+}
+
+.ds-lb-range {
+  flex: 1 1 auto;
+  min-width: 0;
+  height: 44px;
+  margin: 0;
+  background: transparent;
+  appearance: none;
+  -webkit-appearance: none;
+  cursor: pointer;
+
+  &::-webkit-slider-runnable-track {
+    height: 3px;
+    background: rgba(255, 255, 255, 0.22);
+  }
+
+  &::-moz-range-track {
+    height: 3px;
+    background: rgba(255, 255, 255, 0.22);
+  }
+
+  &::-webkit-slider-thumb {
+    -webkit-appearance: none;
+    width: 14px;
+    height: 14px;
+    margin-top: -5.5px;
+    border: 0;
+    border-radius: 0;
+    background: var(--slash);
+  }
+
+  &::-moz-range-thumb {
+    width: 14px;
+    height: 14px;
+    border: 0;
+    border-radius: 0;
+    background: var(--slash);
+  }
+
+  &:focus-visible {
+    outline: 2px solid var(--slash);
+    outline-offset: 2px;
+  }
+}
+
+.ds-lb-chapters {
+  display: flex;
+  flex: none; /* é filha de coluna flex: sem isto a fileira rolável encolhe a quase nada em celular baixo */
+  flex-wrap: wrap;
+  gap: 8px;
+  list-style: none;
+
+  & button {
+    min-height: 36px;
+    padding: 0 12px;
+    font-family: var(--font-mono);
+    font-size: 10px;
+    letter-spacing: 0.08em;
+    text-transform: uppercase;
+    white-space: nowrap;
+    color: rgba(255, 255, 255, 0.7);
+    background: transparent;
+    border: 1px solid rgba(255, 255, 255, 0.14);
+    cursor: pointer;
+    transition:
+      color 0.2s ease,
+      border-color 0.2s ease;
+
+    & span {
+      color: var(--slash);
+    }
+
+    @media (hover: hover) {
+      &:hover {
+        color: #fff;
+        border-color: rgba(255, 255, 255, 0.4);
+      }
+    }
+
+    &[aria-current="true"] {
+      color: #fff;
+      border-color: var(--slash);
+    }
+
+    &:focus-visible {
+      outline: 2px solid var(--slash);
+      outline-offset: -4px;
+    }
+  }
+}
+
+@media (pointer: coarse) {
+  .ds-lb-chapters button {
+    min-height: 44px;
+  }
+}
+
+.ds-lb-links {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--sp-3);
+
+  & .ds-link-muted {
+    color: #fff;
+    border-color: rgba(255, 255, 255, 0.18);
+  }
+}
+
+@media (max-width: 639px) {
+  .ds-lb {
+    padding: 0;
+  }
+
+  .ds-lb-panel {
+    width: 100%;
+    height: 100%;
+    border: 0;
+  }
+
+  .ds-lb-chapters {
+    flex-wrap: nowrap;
+    overflow-x: auto;
+    scrollbar-width: none;
+    padding-bottom: 2px;
+  }
+
+  .ds-lb-chapters::-webkit-scrollbar {
+    display: none;
+  }
+
+  .ds-lb-time {
+    display: none;
+  }
+}
+
+/* telas muito estreitas: nome, versão e setas não cabem na mesma linha; o alternador de versão ocupa uma só */
+@media (max-width: 389px) {
+  .ds-lb-panel {
+    gap: var(--sp-3);
+  }
+
+  .ds-lb-heading {
+    flex-basis: 0;
+  }
+
+  .ds-lb-toggle {
+    order: 3;
+    flex: 1 1 100%;
+  }
+
+  .ds-lb-toggle button {
+    flex: 1;
+  }
+}
+
+/* celular deitado: vídeo grande ao lado, controles em coluna (empilhado, o vídeo ficava com 200px de altura) */
+@media (max-height: 520px) and (min-width: 640px) {
+  .ds-lb {
+    padding: 0;
+  }
+
+  .ds-lb-panel {
+    display: grid;
+    grid-template-columns: minmax(260px, 320px) minmax(0, 1fr);
+    grid-template-rows: auto auto minmax(0, 1fr) auto;
+    grid-template-areas:
+      "head stage"
+      "ctrl stage"
+      "chap stage"
+      "links stage";
+    gap: var(--sp-3) var(--sp-4);
+    width: 100%;
+    height: 100%;
+    border: 0;
+  }
+
+  .ds-lb-head {
+    grid-area: head;
+  }
+
+  .ds-lb-controls {
+    grid-area: ctrl;
+  }
+
+  .ds-lb-chapters {
+    grid-area: chap;
+    flex-wrap: nowrap;
+    overflow-x: auto;
+    scrollbar-width: none;
+  }
+
+  .ds-lb-chapters::-webkit-scrollbar {
+    display: none;
+  }
+
+  .ds-lb-links {
+    grid-area: links;
+  }
+
+  .ds-lb-stage {
+    grid-area: stage;
+    min-height: 0;
+  }
+}
diff --git a/lib/project-showcase.test.ts b/lib/project-showcase.test.ts
new file mode 100644
index 0000000..b7de05e
--- /dev/null
+++ b/lib/project-showcase.test.ts
@@ -0,0 +1,94 @@
+import { existsSync, statSync } from "node:fs";
+import { join } from "node:path";
+import {
+  chapterAnchors,
+  chapterFraction,
+  chapterIndexAt,
+  desktopFractionAt,
+  getOgImagePath,
+  getProjectVideo,
+  getScrubSource,
+  getShowcaseAssets,
+  mobileFractionAt,
+  PROJECT_VIDEO_IDS,
+  SHOWCASE,
+} from "./project-showcase";
+
+const MAX_BYTES = 3 * 1024 * 1024;
+const publicFile = (path: string) => join(process.cwd(), "public", path);
+
+describe("showcase chapters", () => {
+  it.each(SHOWCASE)("$id has ordered chapters inside both videos", (config) => {
+    const [first] = config.chapters;
+    expect(first.desktop).toBe(0);
+    expect(first.mobile).toBe(0);
+    config.chapters.forEach((chapter, index) => {
+      expect(chapter.label.trim()).not.toBe("");
+      expect(chapter.desktop).toBeLessThan(config.durations.desktop);
+      expect(chapter.mobile).toBeLessThan(config.durations.mobile);
+      if (index > 0) {
+        expect(chapter.desktop).toBeGreaterThan(
+          config.chapters[index - 1].desktop,
+        );
+        expect(chapter.mobile).toBeGreaterThan(
+          config.chapters[index - 1].mobile,
+        );
+      }
+    });
+    expect(config.weight).toBeGreaterThan(0);
+  });
+
+  it.each(SHOWCASE)("$id keeps the two timelines in sync", (config) => {
+    const anchors = chapterAnchors(config);
+    expect(anchors[0]).toEqual([0, 0]);
+    expect(anchors[anchors.length - 1]).toEqual([1, 1]);
+    for (const fraction of [0, 0.13, 0.5, 0.77, 1]) {
+      const mobile = mobileFractionAt(config, fraction);
+      expect(mobile).toBeGreaterThanOrEqual(0);
+      expect(mobile).toBeLessThanOrEqual(1);
+      expect(desktopFractionAt(config, mobile)).toBeCloseTo(fraction, 9);
+    }
+    config.chapters.forEach((_, index) => {
+      expect(
+        mobileFractionAt(config, chapterFraction(config, index, "desktop")),
+      ).toBeCloseTo(chapterFraction(config, index, "mobile"), 9);
+    });
+  });
+
+  it("finds the chapter on screen", () => {
+    const lavacao = SHOWCASE.find((config) => config.id === "lavacao-047");
+    expect(lavacao).toBeDefined();
+    if (!lavacao) return;
+    expect(chapterIndexAt(lavacao, 0)).toBe(0);
+    expect(chapterIndexAt(lavacao, 3 / lavacao.durations.desktop)).toBe(1);
+    expect(chapterIndexAt(lavacao, 10 / lavacao.durations.desktop)).toBe(2);
+    expect(chapterIndexAt(lavacao, 1)).toBe(lavacao.chapters.length - 1);
+    expect(chapterIndexAt(lavacao, 2)).toBe(lavacao.chapters.length - 1);
+    expect(chapterIndexAt(lavacao, -1)).toBe(0);
+  });
+});
+
+describe("showcase assets", () => {
+  it("returns undefined for projects without a recorded video", () => {
+    expect(getProjectVideo("reddit-explorer")).toBeUndefined();
+  });
+
+  it.each(PROJECT_VIDEO_IDS)(
+    "has every file on disk for %s, each video within 3 MB",
+    (id) => {
+      const files = [
+        ...(["desktop", "mobile"] as const).flatMap((device) => {
+          const assets = getShowcaseAssets(id, device);
+          return [assets.poster, ...assets.sources.map((s) => s.src)];
+        }),
+        getScrubSource(id, "desktop"),
+        getScrubSource(id, "mobile"),
+        getOgImagePath(id),
+      ];
+      for (const file of files) {
+        expect(existsSync(publicFile(file))).toBe(true);
+        expect(statSync(publicFile(file)).size).toBeLessThanOrEqual(MAX_BYTES);
+      }
+    },
+  );
+});
diff --git a/lib/project-showcase.ts b/lib/project-showcase.ts
new file mode 100644
index 0000000..9ab7628
--- /dev/null
+++ b/lib/project-showcase.ts
@@ -0,0 +1,211 @@
+/**
+ * Vitrine dos projetos: tudo o que os cards, a vitrine animada e a janela ampliada sabem sobre os vídeos.
+ *
+ * Arquivos em public/videos/<id>/ (gravados com scripts/record-project-videos.mjs):
+ * - desktop.{webm,mp4,webp} e mobile.{webm,mp4,webp}: reprodução normal, até 3 MB cada vídeo;
+ * - scrub-desktop.mp4 e scrub-mobile.mp4: mesmos vídeos com um quadro-chave a cada 6 quadros, para a imagem
+ *   acompanhar a rolagem sem travar quando o tempo é mudado a cada quadro;
+ * - og.jpg: capa 1200x630 das imagens de compartilhamento.
+ */
+
+export interface ShowcaseChapter {
+  label: string;
+  /** Segundo do vídeo desktop em que o trecho começa. */
+  desktop: number;
+  /** Segundo do vídeo mobile em que o mesmo trecho começa (as páginas têm alturas diferentes). */
+  mobile: number;
+}
+
+export interface ShowcaseConfig {
+  id: string;
+  /** Cor de destaque do site, usada só no brilho ao redor do vídeo. */
+  accent: string;
+  /** Duração dos vídeos gravados, em segundos (os capítulos são medidos nelas). */
+  durations: { desktop: number; mobile: number };
+  /** Comprimento da rolagem deste projeto na vitrine, em alturas de tela. */
+  weight: number;
+  chapters: readonly ShowcaseChapter[];
+}
+
+/** Ordem da vitrine = ordem dos cards na home. Capítulos marcados nos quadros dos próprios vídeos. */
+export const SHOWCASE: readonly ShowcaseConfig[] = [
+  {
+    id: "sev-modaintima",
+    accent: "#c2303a",
+    durations: { desktop: 17.9, mobile: 30.1 },
+    weight: 1,
+    chapters: [
+      { label: "Abertura", desktop: 0, mobile: 0 },
+      { label: "Categorias", desktop: 2.7, mobile: 1.9 },
+      { label: "As favoritas", desktop: 7.2, mobile: 5.6 },
+      { label: "Nossa essência", desktop: 10.7, mobile: 8.6 },
+      { label: "Coleção completa", desktop: 13.4, mobile: 11 },
+    ],
+  },
+  {
+    id: "lavacao-047",
+    accent: "#4aa3ff",
+    durations: { desktop: 30.07, mobile: 30.1 },
+    weight: 1.4,
+    chapters: [
+      { label: "Abertura", desktop: 0, mobile: 0 },
+      { label: "Tabela de preços", desktop: 1.5, mobile: 1.9 },
+      { label: "Do sujo ao brilho", desktop: 5.5, mobile: 5.6 },
+      { label: "Como funciona", desktop: 13.5, mobile: 13.2 },
+      { label: "Galeria e mapa", desktop: 18.5, mobile: 17.5 },
+      { label: "Perguntas e contato", desktop: 24, mobile: 22 },
+    ],
+  },
+  {
+    id: "nutriscan",
+    accent: "#2f9e5f",
+    durations: { desktop: 15.67, mobile: 26.4 },
+    weight: 0.9,
+    chapters: [
+      { label: "Busca", desktop: 0, mobile: 0 },
+      { label: "Por que confiar", desktop: 2.3, mobile: 3 },
+      { label: "Quatro etapas", desktop: 7, mobile: 8 },
+      { label: "Apoio ao projeto", desktop: 10.9, mobile: 16.3 },
+    ],
+  },
+  {
+    id: "sc-plus",
+    accent: "#22c55e",
+    durations: { desktop: 13, mobile: 19.67 },
+    weight: 0.85,
+    chapters: [
+      { label: "Abertura", desktop: 0, mobile: 0 },
+      { label: "Sobre", desktop: 1.5, mobile: 2.2 },
+      { label: "Áreas e projetos", desktop: 3.8, mobile: 4.6 },
+      { label: "Apoiadores e participação", desktop: 7.5, mobile: 12.8 },
+      { label: "Contato", desktop: 10.4, mobile: 16.9 },
+    ],
+  },
+  {
+    id: "as-servicos",
+    accent: "#2563eb",
+    durations: { desktop: 5.07, mobile: 7.7 },
+    weight: 0.6,
+    chapters: [
+      { label: "Três áreas", desktop: 0, mobile: 0 },
+      { label: "Critérios de entrega", desktop: 1.5, mobile: 3 },
+      { label: "Contato direto", desktop: 2.4, mobile: 4.4 },
+    ],
+  },
+];
+
+export const PROJECT_VIDEO_IDS = SHOWCASE.map((config) => config.id);
+
+const byId = new Map(SHOWCASE.map((config) => [config.id, config]));
+
+export function getShowcaseConfig(id: string): ShowcaseConfig | undefined {
+  return byId.get(id);
+}
+
+export type Device = "desktop" | "mobile";
+
+export interface ShowcaseAssets {
+  poster: string;
+  width: number;
+  height: number;
+  sources: Array<{ src: string; type: string }>;
+}
+
+export function getShowcaseAssets(id: string, device: Device) {
+  const base = `/videos/${id}/${device}`;
+  return {
+    poster: `${base}.webp`,
+    width: device === "desktop" ? 1440 : 390,
+    height: device === "desktop" ? 900 : 844,
+    sources: [
+      { src: `${base}.webm`, type: 'video/webm; codecs="vp9"' },
+      { src: `${base}.mp4`, type: "video/mp4" },
+    ],
+  } satisfies ShowcaseAssets;
+}
+
+export function getScrubSource(id: string, device: Device) {
+  return `/videos/${id}/scrub-${device}.mp4`;
+}
+
+export function getOgImagePath(id: string) {
+  return `/videos/${id}/og.jpg`;
+}
+
+/** Vídeo desktop de um projeto da vitrine: é o que as capas dos cards tocam. */
+export function getProjectVideo(id: string): ShowcaseAssets | undefined {
+  return byId.has(id) ? getShowcaseAssets(id, "desktop") : undefined;
+}
+
+// ---------------------------------------------------------------------------------------------------------
+// Capítulos e sincronia entre as duas telas
+// ---------------------------------------------------------------------------------------------------------
+
+/** Pontos [fração do desktop, fração do mobile] que dizem onde cada capítulo começa em cada vídeo. */
+export function chapterAnchors(
+  config: ShowcaseConfig,
+): Array<[number, number]> {
+  const { desktop, mobile } = config.durations;
+  const points: Array<[number, number]> = [[0, 0]];
+  for (const chapter of config.chapters) {
+    const point: [number, number] = [
+      chapter.desktop / desktop,
+      chapter.mobile / mobile,
+    ];
+    const last = points[points.length - 1];
+    if (point[0] > last[0] && point[1] > last[1]) points.push(point);
+  }
+  points.push([1, 1]);
+  return points;
+}
+
+function interpolate(
+  points: Array<[number, number]>,
+  value: number,
+  from: 0 | 1,
+): number {
+  const to = from === 0 ? 1 : 0;
+  const x = Math.min(1, Math.max(0, value));
+  for (let i = 1; i < points.length; i += 1) {
+    const [a, b] = [points[i - 1], points[i]];
+    if (x <= b[from]) {
+      const span = b[from] - a[from];
+      const ratio = span === 0 ? 0 : (x - a[from]) / span;
+      return a[to] + ratio * (b[to] - a[to]);
+    }
+  }
+  return 1;
+}
+
+/** Fração do vídeo mobile que mostra o mesmo ponto do site que a fração `fraction` do vídeo desktop. */
+export function mobileFractionAt(config: ShowcaseConfig, fraction: number) {
+  return interpolate(chapterAnchors(config), fraction, 0);
+}
+
+/** O contrário: fração do desktop para uma fração do vídeo mobile. */
+export function desktopFractionAt(config: ShowcaseConfig, fraction: number) {
+  return interpolate(chapterAnchors(config), fraction, 1);
+}
+
+/** Capítulo em exibição quando o vídeo desktop está na fração `fraction`. */
+export function chapterIndexAt(config: ShowcaseConfig, fraction: number) {
+  const seconds = Math.min(1, Math.max(0, fraction)) * config.durations.desktop;
+  let index = 0;
+  config.chapters.forEach((chapter, i) => {
+    if (seconds >= chapter.desktop - 1e-6) index = i;
+  });
+  return index;
+}
+
+/** Fração (0 a 1) do vídeo `device` em que o capítulo `index` começa. */
+export function chapterFraction(
+  config: ShowcaseConfig,
+  index: number,
+  device: Device,
+) {
+  const chapter = config.chapters[index];
+  if (!chapter) return 0;
+  return device === "desktop"
+    ? chapter.desktop / config.durations.desktop
+    : chapter.mobile / config.durations.mobile;
+}
diff --git a/lib/project-videos.ts b/lib/project-videos.ts
deleted file mode 100644
index 5e0db07..0000000
--- a/lib/project-videos.ts
+++ /dev/null
@@ -1,34 +0,0 @@
-/**
- * Vídeos de rolagem dos projetos: public/videos/<id>/desktop.{webm,mp4,webp}.
- * Gravados com scripts/record-project-videos.mjs; só entram aqui os ids que têm os três arquivos.
- */
-export interface ProjectVideoAsset {
-  poster: string;
-  width: number;
-  height: number;
-  sources: Array<{ src: string; type: string }>;
-}
-
-export const PROJECT_VIDEO_IDS = [
-  "sev-modaintima",
-  "lavacao-047",
-  "nutriscan",
-  "sc-plus",
-  "as-servicos",
-] as const;
-
-const recorded = new Set<string>(PROJECT_VIDEO_IDS);
-
-export function getProjectVideo(id: string): ProjectVideoAsset | undefined {
-  if (!recorded.has(id)) return undefined;
-  const base = `/videos/${id}/desktop`;
-  return {
-    poster: `${base}.webp`,
-    width: 1440,
-    height: 900,
-    sources: [
-      { src: `${base}.webm`, type: 'video/webm; codecs="vp9"' },
-      { src: `${base}.mp4`, type: "video/mp4" },
-    ],
-  };
-}