.sidebar {
  width: 280px;
  min-width: 280px;
  background: var(--bg2);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.sidebar-header-actions {
  display: flex;
  align-items: center;
  gap: 4px;
}

.sidebar-close-btn {
  display: none;
}

/* ── Header ── */
.sidebar-header {
  display: flex;
  align-items: center;
  padding: 16px 16px 12px;
  border-bottom: 1px solid var(--border);
  gap: 8px;
  flex-shrink: 0;
}

.sidebar-brand {
  display: flex;
  align-items: center;
  flex: 1;
  min-width: 0;
}

.brand-name {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text);
}

.icon-btn {
  background: none;
  border: none;
  color: var(--text3);
  cursor: pointer;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  transition: background 0.15s, color 0.15s;
  flex-shrink: 0;
  padding: 0;
}

.icon-btn:hover {
  background: var(--bg4);
  color: var(--text);
}

/* ── Model section ── */
.model-section {
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.model-section-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--text3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 6px;
}

.model-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  flex-shrink: 0;
  transition: background 0.3s, box-shadow 0.3s;
}

.status-dot.status-ok {
  background: var(--success);
  box-shadow: 0 0 6px rgba(48,209,88,0.5);
}

.status-dot.status-error {
  background: var(--danger);
}

.status-dot.status-loading {
  background: var(--warning);
  animation: pulse 1.2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.35; }
}

.model-select {
  flex: 1;
  background: transparent;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 13px;
  padding: 6px 28px 6px 8px;
  outline: none;
  cursor: pointer;
  min-width: 0;
  font-family: inherit;
  transition: border-color 0.15s, background 0.15s;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6' viewBox='0 0 10 6'%3E%3Cpath d='M0 0l5 6 5-6z' fill='%236b7280'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 8px center;
}

.model-select:hover {
  background-color: var(--bg3);
  border-color: var(--border);
}

.model-select:focus {
  border-color: var(--accent);
  background-color: var(--bg3);
}

.model-select:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ── Sidebar actions ── */
.sidebar-actions {
  padding: 10px 16px 6px;
  flex-shrink: 0;
}

.new-chat-btn {
  width: 100%;
  background: var(--bg3);
  color: var(--text2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 8px;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
  font-family: inherit;
  height: 36px;
}

.new-chat-btn:hover {
  background: var(--bg4);
  color: var(--text);
  border-color: var(--border);
}

.new-chat-btn:active {
  transform: scale(0.98);
}

/* ── Chat list ── */
.chat-list-section-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--text3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 12px 16px 4px;
  flex-shrink: 0;
}

.chat-list {
  flex: 1;
  overflow-y: auto;
  padding: 4px 8px 8px;
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.chat-list-empty {
  text-align: center;
  color: var(--text3);
  font-size: 12px;
  padding: 24px 0;
  line-height: 1.6;
}

.chat-item {
  display: flex;
  align-items: center;
  gap: 4px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: var(--text2);
  transition: background 0.12s, color 0.12s;
  position: relative;
}

.chat-item-button {
  flex: 1;
  min-width: 0;
  display: flex;
  align-items: center;
  padding: 8px 10px;
  background: transparent;
  border: 0;
  color: inherit;
  cursor: pointer;
  font: inherit;
  text-align: left;
  border-radius: var(--radius-sm);
}

.chat-item:hover {
  background: var(--bg3);
  color: var(--text);
}

.chat-item:focus-within {
  background: var(--bg3);
  color: var(--text);
}

.chat-item.active {
  background: var(--bg4);
  color: var(--text);
}

.chat-item-title {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-size: 13px;
  line-height: 1.4;
}

.chat-item-del {
  opacity: 0;
  background: none;
  border: none;
  color: var(--text3);
  cursor: pointer;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  transition: opacity 0.15s, background 0.15s, color 0.15s;
  flex-shrink: 0;
  padding: 0;
  margin-right: 4px;
}

.chat-item:hover .chat-item-del {
  opacity: 1;
}

.chat-item:focus-within .chat-item-del,
.chat-item.active .chat-item-del {
  opacity: 1;
}

.chat-item-del:hover {
  background: rgba(240,64,64,0.15);
  color: var(--danger);
}

/* ── Footer ── */
.sidebar-footer {
  padding: 8px 16px;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-shrink: 0;
}

.footer-version {
  font-size: 10px;
  color: var(--text3);
  letter-spacing: 0.02em;
}

@media (max-width: 960px) {
  .sidebar {
    position: fixed;
    inset: 0 auto 0 0;
    width: min(86vw, 320px);
    min-width: 0;
    z-index: 20;
    transform: translateX(-100%);
    transition: transform 0.22s ease, box-shadow 0.22s ease;
    box-shadow: none;
  }

  .sidebar-open .sidebar {
    transform: translateX(0);
    box-shadow: var(--shadow-lg);
  }

  .sidebar-close-btn {
    display: inline-flex;
  }
}

@media (hover: none), (max-width: 960px) {
  .chat-item-del {
    opacity: 1;
  }
}