/* Mobile: 320px - 767px */
@media (max-width: 767px) {
  html { font-size: 15px; }

  .sidebar {
    width: 100%;
    max-width: 100%;
    position: fixed;
    top: 0;
    left: 0;
    bottom: auto;
    height: auto;
    z-index: var(--z-sticky);
    transform: translateY(-100%);
    transition: transform var(--transition-base);
    border-right: none;
    border-bottom: 1px solid var(--hairline);
  }
  .sidebar.open {
    transform: translateY(0);
  }
  .sidebar-toggle {
    display: flex;
  }

  .dashboard-main {
    padding-top: var(--space-xxl);
  }
  .dashboard-grid {
    grid-template-columns: 1fr;
  }
  .dashboard-header {
    flex-direction: column;
    gap: var(--space-xs);
  }

  .board-toolbar {
    position: fixed;
    bottom: 0;
    top: auto;
    left: 0;
    right: 0;
    height: 48px;
    overflow-x: auto;
    overflow-y: hidden;
    border-top: 1px solid var(--hairline);
    border-bottom: none;
    z-index: var(--z-sticky);
    background: var(--surface);
    -webkit-overflow-scrolling: touch;
  }
  .board-toolbar::-webkit-scrollbar { display: none; }
  .board-canvas {
    bottom: 48px;
    top: 0;
  }
  .toolbar-label { display: none; }
  .toolbar-divider { margin: 0 2px; }
  .toolbar-btn { min-width: 36px; }

  .minimap {
    width: 100px;
    height: 70px;
    bottom: 56px;
    right: var(--space-xs);
  }

  .modal-wrapper .modal {
    width: 92vw;
    max-width: 92vw;
    margin: 0;
    border-radius: var(--radius-lg);
  }

  .context-menu {
    min-width: 160px;
  }

  .ai-assistant-panel {
    width: 100%;
    max-width: 100%;
    right: 0;
    border-radius: 0;
  }

  .chat-panel {
    width: 100%;
    max-width: 100%;
    right: 0;
    border-radius: 0;
  }

  .share-dialog .modal {
    max-height: 80vh;
  }

  .file-manager {
    width: 100%;
    max-width: 100%;
    right: 0;
    border-radius: 0;
  }

  .media-player-modal .modal {
    width: 95vw;
  }

  .template-gallery-grid {
    grid-template-columns: 1fr 1fr;
  }

  .auth-card {
    width: 92vw;
    padding: var(--space-lg);
  }

  .board-item {
    touch-action: manipulation;
  }
  .item-resize-handle {
    width: 20px;
    height: 20px;
  }
}

/* Tablet: 768px - 1023px */
@media (min-width: 768px) and (max-width: 1023px) {
  html { font-size: 15px; }

  .sidebar { width: 220px; }
  .dashboard-main { margin-left: 220px; }

  .dashboard-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .board-canvas {
    top: var(--toolbar-height);
    bottom: 0;
    left: 0;
    right: 0;
  }

  .template-gallery-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .modal-wrapper .modal {
    width: 80vw;
    max-width: 600px;
  }

  .ai-assistant-panel {
    width: 340px;
  }

  .chat-panel {
    width: 340px;
  }

  .minimap {
    width: 130px;
    height: 90px;
  }
}

/* Desktop: 1024px+ */
@media (min-width: 1024px) {
  .dashboard-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .dashboard-grid:has(.board-card:only-child) {
    grid-template-columns: 1fr;
    max-width: 400px;
  }
  .template-gallery-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* Large Desktop: 1440px+ */
@media (min-width: 1440px) {
  .dashboard-grid {
    grid-template-columns: repeat(4, 1fr);
  }
  .template-gallery-grid {
    grid-template-columns: repeat(5, 1fr);
  }
}

.sidebar-toggle {
  display: none;
  position: fixed;
  top: var(--space-xs);
  left: var(--space-xs);
  z-index: calc(var(--z-sticky) + 1);
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  background: var(--surface);
  border: 1px solid var(--hairline);
  font-size: var(--text-body);
  cursor: pointer;
  align-items: center;
  justify-content: center;
}

.pwa-install-banner {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-md);
  background: var(--primary);
  color: var(--ink-inverse);
  font-size: var(--text-caption);
  border-radius: var(--radius-md);
  cursor: pointer;
}
.pwa-install-banner:hover {
  background: var(--primary-active);
}

@media print {
  .sidebar, .board-toolbar, .minimap, .context-menu,
  .modal-wrapper, .toast-container, .ai-assistant-panel,
  .chat-panel, .file-manager, .media-player-modal {
    display: none !important;
  }
  .board-canvas {
    position: static;
    overflow: visible;
  }
  .canvas-container {
    transform: none !important;
  }
  #canvas { overflow: visible; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

@media (prefers-contrast: high) {
  :root {
    --hairline: #000;
  }
  [data-theme="dark"] {
    --hairline: #fff;
  }
}