:root {
  --bg-primary: #0a0a1a;
  --bg-secondary: #12122a;
  --bg-tertiary: #1a1a3e;
  --glass-bg: rgba(255, 255, 255, 0.04);
  --glass-border: rgba(255, 255, 255, 0.08);
  --glass-hover: rgba(255, 255, 255, 0.08);
  --glass-active: rgba(99, 102, 241, 0.15);
  --accent: #6366f1;
  --accent-hover: #818cf8;
  --accent-glow: rgba(99, 102, 241, 0.3);
  --text-primary: #e8e8f0;
  --text-secondary: #8888aa;
  --text-muted: #555577;
  --danger: #ef4444;
  --danger-hover: #f87171;
  --success: #22c55e;
  --warning: #eab308;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --transition: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --sidebar-width: 260px;
  --toolbar-width: 64px;
  --topbar-height: 52px;
}

*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html, body {
  height: 100%;
  overflow: hidden;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
}

::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--text-muted); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-secondary); }

.glass {
  background: var(--glass-bg);
  backdrop-filter: blur(20px) saturate(1.2);
  -webkit-backdrop-filter: blur(20px) saturate(1.2);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
}

.hidden { display: none !important; }

/* Modal */
.modal-overlay {
  position: fixed; inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  display: flex; align-items: center; justify-content: center;
  z-index: 1000;
  animation: fadeIn 200ms ease;
}

.modal {
  width: 400px; max-width: 90vw;
  padding: 32px;
  animation: modalIn 300ms ease;
}

.modal-sm { width: 360px; }

.modal-header { text-align: center; margin-bottom: 24px; }
.modal-header h2 { font-size: 1.5rem; font-weight: 700; background: linear-gradient(135deg, var(--accent), #a78bfa); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.modal-subtitle { font-size: 0.85rem; color: var(--text-secondary); margin-top: 4px; }

.modal-body {
  display: flex; flex-direction: column; gap: 16px;
}

.form-group { display: flex; flex-direction: column; gap: 6px; }
.form-group label { font-size: 0.8rem; font-weight: 500; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 0.5px; }
.form-group input {
  padding: 10px 14px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 0.9rem;
  outline: none;
  transition: var(--transition);
}
.form-group input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.auth-error { color: var(--danger); font-size: 0.85rem; text-align: center; }

.btn {
  padding: 10px 20px;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
}
.btn-primary {
  background: var(--accent);
  color: white;
}
.btn-primary:hover { background: var(--accent-hover); box-shadow: 0 0 20px var(--accent-glow); }
.btn-secondary {
  background: rgba(255,255,255,0.06);
  color: var(--text-primary);
  border: 1px solid var(--glass-border);
}
.btn-secondary:hover { background: rgba(255,255,255,0.1); }
.btn-sm { padding: 6px 14px; font-size: 0.8rem; }

.link-btn {
  background: none;
  border: none;
  color: var(--accent);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 600;
}
.link-btn:hover { color: var(--accent-hover); }

.auth-switch { text-align: center; font-size: 0.85rem; color: var(--text-secondary); }
.divider { display: flex; align-items: center; gap: 12px; color: var(--text-muted); font-size: 0.8rem; }
.divider::before, .divider::after { content: ''; flex: 1; height: 1px; background: var(--glass-border); }

/* Topbar */
#topbar {
  height: var(--topbar-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  background: rgba(10, 10, 26, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--glass-border);
  z-index: 100;
  position: relative;
}

.topbar-left, .topbar-center, .topbar-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo { font-size: 1.2rem; font-weight: 800; letter-spacing: -0.5px; }
.accent { color: var(--accent); }

.room-info { display: flex; align-items: center; gap: 6px; font-size: 0.85rem; }
.room-label { color: var(--text-secondary); }
.room-id {
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 1px;
}

.icon-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 6px;
  border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center;
  transition: var(--transition);
}
.icon-btn:hover { color: var(--text-primary); background: var(--glass-hover); }
.icon-btn:disabled { opacity: 0.3; cursor: not-allowed; }
.icon-btn.danger:hover { color: var(--danger); background: rgba(239,68,68,0.1); }
.icon-btn-sm {
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  cursor: pointer;
  width: 28px; height: 28px;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  display: flex; align-items: center; justify-content: center;
  transition: var(--transition);
}
.icon-btn-sm:hover { background: rgba(255,255,255,0.1); }

.divider-v { width: 1px; height: 24px; background: var(--glass-border); }
.divider-h { height: 1px; width: 100%; background: var(--glass-border); margin: 8px 0; }

.user-avatar {
  width: 32px; height: 32px;
  border-radius: 50%;
  background: var(--accent);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.8rem; font-weight: 700;
  cursor: pointer;
  position: relative;
  transition: var(--transition);
}
.user-avatar:hover { box-shadow: 0 0 16px var(--accent-glow); }

.dropdown {
  position: absolute;
  top: 38px;
  right: 0;
  background: var(--bg-secondary);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  padding: 8px;
  min-width: 180px;
  box-shadow: var(--shadow);
  z-index: 200;
}
.dropdown hr { border: none; border-top: 1px solid var(--glass-border); margin: 6px 0; }
.dropdown-user { padding: 4px 8px; font-size: 0.85rem; }
.dropdown-item {
  display: block;
  width: 100%;
  padding: 8px 12px;
  text-align: left;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 0.85rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
}
.dropdown-item:hover { background: var(--glass-hover); }

/* Main Content */
#main-content {
  display: flex;
  height: calc(100vh - var(--topbar-height));
  position: relative;
}

/* Toolbar */
#toolbar {
  width: var(--toolbar-width);
  background: rgba(10, 10, 26, 0.8);
  backdrop-filter: blur(20px);
  border-right: 1px solid var(--glass-border);
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 12px 8px;
  gap: 4px;
  z-index: 50;
}

.tool-group {
  display: flex;
  flex-direction: column;
  gap: 2px;
  width: 100%;
}

.tool-btn {
  width: 48px; height: 48px;
  display: flex; align-items: center; justify-content: center;
  background: none;
  border: none;
  color: var(--text-secondary);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: var(--transition);
  position: relative;
}
.tool-btn:hover { color: var(--text-primary); background: var(--glass-hover); }
.tool-btn.active {
  color: var(--accent);
  background: var(--glass-active);
}
.tool-btn.active::before {
  content: '';
  position: absolute;
  left: -8px;
  width: 3px;
  height: 20px;
  background: var(--accent);
  border-radius: 0 3px 3px 0;
}

.tool-setting {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 8px 0;
}

.setting-label {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-muted);
  font-weight: 600;
}

#color-picker {
  width: 32px; height: 32px;
  border: 2px solid var(--glass-border);
  border-radius: 50%;
  cursor: pointer;
  padding: 0;
  background: none;
}
#color-picker::-webkit-color-swatch-wrapper { padding: 0; }
#color-picker::-webkit-color-swatch { border: none; border-radius: 50%; }

.size-control {
  display: flex;
  align-items: center;
  gap: 4px;
}
#stroke-width {
  width: 40px;
  height: 4px;
  -webkit-appearance: none;
  appearance: none;
  background: var(--glass-border);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
}
#stroke-width::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 14px; height: 14px;
  background: var(--accent);
  border-radius: 50%;
  cursor: pointer;
}
#stroke-width-label {
  font-size: 0.75rem;
  color: var(--text-secondary);
  width: 16px;
  text-align: center;
  font-weight: 600;
}

/* Canvas */
#canvas-container {
  flex: 1;
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(99, 102, 241, 0.03) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 50%, rgba(167, 139, 250, 0.03) 0%, transparent 50%);
}

#whiteboard {
  display: block;
  position: absolute;
  top: 0; left: 0;
  cursor: crosshair;
}

#whiteboard.panning { cursor: grab; }
#whiteboard.panning:active { cursor: grabbing; }
#whiteboard.eraser-mode { cursor: cell; }

#cursors-layer {
  position: absolute;
  top: 0; left: 0;
  pointer-events: none;
  z-index: 10;
}

.remote-cursor {
  position: absolute;
  transition: transform 100ms linear;
  pointer-events: none;
}
.remote-cursor svg { filter: drop-shadow(0 2px 4px rgba(0,0,0,0.3)); }
.remote-label {
  position: absolute;
  top: 20px; left: 12px;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 0.7rem;
  font-weight: 600;
  white-space: nowrap;
  background: rgba(0,0,0,0.6);
  color: white;
}

/* Zoom Controls */
#zoom-controls {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 6px;
  background: rgba(10, 10, 26, 0.8);
  backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 6px 12px;
  z-index: 50;
}
#zoom-level {
  font-size: 0.8rem;
  font-weight: 600;
  min-width: 48px;
  text-align: center;
  color: var(--text-secondary);
}

/* Sticky Notes */
#sticky-notes-container {
  position: absolute;
  top: 0; left: 0;
  pointer-events: none;
  z-index: 5;
}

.sticky-note {
  position: absolute;
  min-width: 160px;
  min-height: 160px;
  background: #fff9c4;
  border-radius: 4px;
  box-shadow: 0 4px 16px rgba(0,0,0,0.2), 0 0 0 1px rgba(0,0,0,0.05);
  pointer-events: all;
  cursor: move;
  display: flex;
  flex-direction: column;
  transition: box-shadow var(--transition);
  font-size: 0.85rem;
  color: #333;
}
.sticky-note:hover { box-shadow: 0 6px 24px rgba(0,0,0,0.3); }
.sticky-note.selected { box-shadow: 0 0 0 2px var(--accent), 0 6px 24px rgba(0,0,0,0.3); }
.sticky-note-header {
  padding: 8px 12px;
  display: flex;
  justify-content: flex-end;
  cursor: move;
  user-select: none;
}
.sticky-note-delete {
  background: none;
  border: none;
  cursor: pointer;
  color: rgba(0,0,0,0.3);
  font-size: 1rem;
  padding: 2px;
  line-height: 1;
  border-radius: 2px;
  transition: var(--transition);
}
.sticky-note-delete:hover { color: rgba(0,0,0,0.7); background: rgba(0,0,0,0.05); }
.sticky-note-body {
  flex: 1;
  padding: 0 12px 12px;
  cursor: text;
}
.sticky-note-body textarea {
  width: 100%;
  height: 100%;
  min-height: 120px;
  background: none;
  border: none;
  outline: none;
  resize: none;
  font-family: inherit;
  font-size: 0.85rem;
  color: #333;
  line-height: 1.5;
}

/* Sidebar */
#sidebar {
  width: var(--sidebar-width);
  background: rgba(10, 10, 26, 0.8);
  backdrop-filter: blur(20px);
  border-left: 1px solid var(--glass-border);
  display: flex;
  flex-direction: column;
  position: relative;
  transition: width var(--transition), opacity var(--transition);
  overflow: hidden;
  z-index: 50;
}
#sidebar.collapsed {
  width: 0;
  opacity: 0;
  border: none;
}

.sidebar-toggle {
  position: absolute;
  left: -36px;
  top: 12px;
  width: 36px; height: 36px;
  background: rgba(10, 10, 26, 0.8);
  backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-right: none;
  border-radius: var(--radius-md) 0 0 var(--radius-md);
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}
.sidebar-toggle:hover { color: var(--text-primary); }
#sidebar.collapsed .sidebar-toggle { left: -36px; }

.sidebar-content {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 20px;
  overflow-y: auto;
  flex: 1;
}

.sidebar-panel {}
.panel-title {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  font-weight: 600;
  margin-bottom: 10px;
}

#user-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.user-list-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  padding: 6px 8px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}
.user-list-item:hover { background: var(--glass-hover); }
.user-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}
.user-list-name {
  flex: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.user-list-me {
  font-size: 0.65rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

#layers-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.layer-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  cursor: pointer;
  transition: var(--transition);
}
.layer-item:hover { background: var(--glass-hover); }
.layer-item.active { background: var(--glass-active); }
.layer-visibility {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 2px;
  display: flex;
}
.layer-visibility:hover { color: var(--text-primary); }
.layer-name { flex: 1; }

.action-btn {
  width: 100%;
  justify-content: flex-start;
  margin-bottom: 4px;
}

/* Minimap */
#minimap {
  position: fixed;
  bottom: 70px;
  right: 16px;
  width: 180px;
  height: 120px;
  background: rgba(10, 10, 26, 0.8);
  backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  z-index: 40;
  transition: var(--transition);
}
#minimap.collapsed { display: none; }
#minimap-canvas { width: 100%; height: 100%; display: block; }

#minimap-toggle {
  position: fixed;
  bottom: 16px;
  right: 16px;
  width: 40px; height: 40px;
  background: rgba(10, 10, 26, 0.8);
  backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  border-radius: 50%;
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 40;
  transition: var(--transition);
}
#minimap-toggle:hover { color: var(--text-primary); background: var(--glass-hover); }

/* Share modal */
.share-code {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--glass-bg);
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--glass-border);
}
#share-room-id {
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 4px;
  color: var(--accent);
  flex: 1;
  text-align: center;
}

.share-link-desc { font-size: 0.8rem; color: var(--text-secondary); }
.share-link-row {
  display: flex;
  gap: 8px;
}
.share-link-row input {
  flex: 1;
  padding: 8px 12px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 0.8rem;
  outline: none;
}

.modal-close {
  position: absolute;
  top: 12px;
  right: 12px;
}

/* Toast */
#toast-container {
  position: fixed;
  top: 70px;
  right: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  z-index: 2000;
  pointer-events: none;
}
.toast {
  padding: 10px 18px;
  background: var(--bg-secondary);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  gap: 8px;
  box-shadow: var(--shadow);
  animation: toastIn 300ms ease, toastOut 300ms ease 2.7s forwards;
  pointer-events: all;
}

/* Animations */
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes modalIn {
  from { opacity: 0; transform: scale(0.95) translateY(10px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}
@keyframes toastIn {
  from { opacity: 0; transform: translateX(20px); }
  to { opacity: 1; transform: translateX(0); }
}
@keyframes toastOut {
  from { opacity: 1; transform: translateX(0); }
  to { opacity: 0; transform: translateX(20px); }
}

/* Responsive */
@media (max-width: 768px) {
  #sidebar { display: none; }
  #toolbar { width: 52px; }
  .tool-btn { width: 36px; height: 36px; }
  .topbar-center { gap: 6px; }
  .room-label { display: none; }
}