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

:root {
  --bg-primary: #1a1b1e;
  --bg-secondary: #25262b;
  --bg-tertiary: #2c2e33;
  --border-color: #373a40;
  --text-primary: #e9ecef;
  --text-secondary: #adb5bd;
  --accent-color: #4c6ef5;
  --accent-hover: #5c7cfa;
  --success-color: #51cf66;
  --danger-color: #ff6b6b;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  overflow: hidden;
  height: 100vh;
}

/* Header */
.header {
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  padding: 0 20px;
  height: 60px;
  display: flex;
  align-items: center;
  z-index: 100;
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.header-title {
  font-size: 20px;
  font-weight: 600;
  color: var(--text-primary);
}

.btn-login {
  background-color: var(--accent-color);
  color: white;
  border: none;
  padding: 8px 20px;
  border-radius: 6px;
  font-size: 14px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-login:hover {
  background-color: var(--accent-hover);
  transform: translateY(-1px);
}

/* Main Container */
.main-container {
  display: flex;
  height: calc(100vh - 60px);
}

/* Sidebar */
.sidebar {
  width: 320px;
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.sidebar-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-color);
}

.sidebar-header h2 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
}

.sidebar-content {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
}

.file-item {
  display: flex;
  align-items: center;
  padding: 10px 12px;
  margin-bottom: 4px;
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.file-item:hover {
  background-color: #33353a;
  border-color: var(--accent-color);
}

.file-item.loaded {
  border-color: var(--success-color);
  background-color: rgba(81, 207, 102, 0.1);
}

.file-checkbox {
  width: 18px;
  height: 18px;
  margin-right: 12px;
  cursor: pointer;
  accent-color: var(--accent-color);
}

.file-visibility {
  margin-left: auto;
  font-size: 18px;
  cursor: pointer;
  transition: opacity 0.2s ease;
}

.file-visibility:hover {
  opacity: 0.7;
}

.file-name {
  flex: 1;
  font-size: 13px;
  color: var(--text-primary);
  word-break: break-word;
}

/* Viewer Container */
.viewer-container {
  flex: 1;
  position: relative;
  overflow: hidden;
}

/* Toolbar */
.toolbar {
  position: absolute;
  top: 16px;
  left: 16px;
  right: 16px;
  background-color: rgba(37, 38, 43, 0.95);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 12px 16px;
  display: flex;
  gap: 8px;
  align-items: center;
  z-index: 10;
  backdrop-filter: blur(10px);
}

.toolbar-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-primary);
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.toolbar-btn:hover {
  background-color: var(--accent-color);
  border-color: var(--accent-color);
  transform: translateY(-1px);
}

.toolbar-btn.active {
  background-color: var(--accent-color);
  border-color: var(--accent-color);
}

.toolbar-btn .icon {
  font-size: 16px;
}

.toolbar-separator {
  width: 1px;
  height: 24px;
  background-color: var(--border-color);
}

/* Canvas */
#three-canvas {
  width: 100%;
  height: 100%;
  display: block;
  cursor: default;
}

#three-canvas.walk-mode {
  cursor: crosshair;
}

/* Loading Indicator */
.loading-indicator {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background-color: rgba(37, 38, 43, 0.95);
  padding: 30px 40px;
  border-radius: 12px;
  border: 1px solid var(--border-color);
  display: none;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  z-index: 50;
}

.loading-indicator.visible {
  display: flex;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid var(--border-color);
  border-top-color: var(--accent-color);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.loading-indicator p {
  font-size: 14px;
  color: var(--text-secondary);
}

/* Context Menu */
.context-menu {
  position: absolute;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 4px;
  min-width: 200px;
  display: none;
  z-index: 1000;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
}

.context-menu.visible {
  display: block;
}

.context-menu-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  cursor: pointer;
  border-radius: 6px;
  transition: all 0.2s ease;
  font-size: 13px;
  color: var(--text-primary);
}

.context-menu-item:hover {
  background-color: var(--accent-color);
}

.context-menu-item .icon {
  font-size: 16px;
}

/* Section Panel */
.section-panel {
  position: absolute;
  bottom: 20px;
  right: 20px;
  background-color: rgba(37, 38, 43, 0.95);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 16px;
  min-width: 280px;
  z-index: 10;
  backdrop-filter: blur(10px);
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.section-header h3 {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
}

.close-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 18px;
  cursor: pointer;
  padding: 0;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  transition: all 0.2s ease;
}

.close-btn:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.section-controls {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.section-controls label {
  font-size: 13px;
  color: var(--text-secondary);
}

.section-slider {
  width: 100%;
  height: 6px;
  background: var(--bg-tertiary);
  border-radius: 3px;
  outline: none;
  -webkit-appearance: none;
}

.section-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  background: var(--accent-color);
  border-radius: 50%;
  cursor: pointer;
  transition: all 0.2s ease;
}

.section-slider::-webkit-slider-thumb:hover {
  background: var(--accent-hover);
  transform: scale(1.1);
}

.section-slider::-moz-range-thumb {
  width: 18px;
  height: 18px;
  background: var(--accent-color);
  border-radius: 50%;
  cursor: pointer;
  border: none;
  transition: all 0.2s ease;
}

.section-slider::-moz-range-thumb:hover {
  background: var(--accent-hover);
  transform: scale(1.1);
}

.section-value {
  text-align: center;
  font-size: 14px;
  color: var(--text-primary);
  font-weight: 600;
}

/* Walk Mode Instructions */
.walk-instructions {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  background-color: rgba(37, 38, 43, 0.95);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 12px 20px;
  z-index: 10;
  backdrop-filter: blur(10px);
}

.walk-instructions p {
  font-size: 13px;
  color: var(--text-secondary);
  margin: 4px 0;
}

.walk-instructions strong {
  color: var(--text-primary);
}

/* Scrollbar Styling */
.sidebar-content::-webkit-scrollbar {
  width: 8px;
}

.sidebar-content::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

.sidebar-content::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 4px;
}

.sidebar-content::-webkit-scrollbar-thumb:hover {
  background: #4a4d55;
}

/* Responsive adjustments */
@media (max-width: 768px) {
  .sidebar {
    width: 280px;
  }
  
  .toolbar {
    flex-wrap: wrap;
  }
  
  .toolbar-btn span:not(.icon) {
    display: none;
  }
}