:root {
  /* Colors */
  --color-primary: #3498db;
  --color-primary-dark: #2980b9;
  --color-secondary: #2c3e50;
  --color-success: #2ecc71;
  --color-success-dark: #27ae60;
  --color-danger: #e74c3c;
  --color-danger-dark: #c0392b;
  --color-warning: #f39c12;
  --color-warning-light: #f1c40f;
  --color-gray-light: #ecf0f1;
  --color-gray: #7f8c8d;
  --color-gray-border: #ddd;
  --color-background: #f5f5f5;
  --color-white: #fff;

  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;

  /* Border radius */
  --radius-sm: 4px;
  --radius-md: 8px;

  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.2);

  /* Transitions */
  --transition-normal: 0.2s;
  --transition-slow: 0.3s;
}

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

/* Screen Reader Only - for accessibility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

body {
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu,
    Cantarell, sans-serif;
  background: var(--color-background);
  overflow: hidden;
}

#app {
  height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  background: var(--color-secondary);
  color: var(--color-white);
  padding: var(--spacing-md) var(--spacing-xl);
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: var(--shadow-sm);
}

header h1 {
  font-size: 1.5rem;
}

.header-controls {
  display: flex;
  gap: var(--spacing-sm);
  align-items: center;
}

.snapshot-controls {
  display: flex;
  gap: var(--spacing-xs);
  align-items: center;
  padding: var(--spacing-xs);
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
}

.container {
  display: flex;
  flex: 1;
  overflow: hidden;
  position: relative;
}

.sidebar {
  width: 320px;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-right: 1px solid rgba(221, 221, 221, 0.5);
  overflow-y: auto;
  padding: 4rem var(--spacing-md) var(--spacing-md) var(--spacing-md);
  position: absolute;
  left: 0;
  top: 0;
  height: 100%;
  transition:
    transform var(--transition-slow) ease,
    opacity var(--transition-slow) ease;
  z-index: 100;
}

.sidebar.hidden {
  transform: translateX(-100%);
  opacity: 0;
  pointer-events: none;
}

.sidebar.unpinned:not(:hover) {
  transform: translateX(-100%);
  opacity: 0;
}

.sidebar-pin-btn {
  position: absolute;
  top: var(--spacing-sm);
  left: var(--spacing-sm);
  background: rgba(52, 152, 219, 0.9);
  color: white;
  border: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition:
    background var(--transition-normal),
    left var(--transition-slow) ease;
  z-index: 102;
  box-shadow: var(--shadow-md);
}

.sidebar:not(.unpinned) ~ .sidebar-pin-btn {
  left: calc(320px - var(--spacing-sm) - 40px);
}

.sidebar-pin-btn:hover {
  background: rgba(41, 128, 185, 0.9);
}

.sidebar-hover-trigger {
  position: absolute;
  left: 0;
  top: 0;
  width: 20px;
  height: 100%;
  z-index: 99;
  pointer-events: all;
}

.sidebar.unpinned + .sidebar-hover-trigger {
  pointer-events: all;
}

.sidebar:not(.unpinned) + .sidebar-hover-trigger {
  pointer-events: none;
}

.btn {
  background: var(--color-primary);
  color: white;
  border: none;
  padding: 0.6rem 1.2rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.9rem;
  transition: background var(--transition-normal);
}

.btn:hover {
  background: var(--color-primary-dark);
}

.btn-danger {
  background: var(--color-danger);
}

.btn-danger:hover {
  background: var(--color-danger-dark);
}

.btn-secondary {
  background: #95a5a6;
  font-size: 0.85rem;
  padding: var(--spacing-sm) var(--spacing-md);
}

.btn-secondary:hover {
  background: var(--color-gray);
}

.btn-warning {
  background: var(--color-warning);
}

.btn-warning:hover {
  background: #e67e22;
}

#floorPlanUpload {
  width: 100%;
  padding: var(--spacing-sm);
  border: 2px dashed var(--color-gray-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.scale-config {
  margin-top: var(--spacing-md);
}

.scale-config label {
  display: block;
  margin-bottom: var(--spacing-sm);
}

.scale-config input,
.scale-config select {
  width: 100%;
  padding: var(--spacing-sm);
  border: 1px solid var(--color-gray-border);
  border-radius: var(--radius-sm);
  margin-top: var(--spacing-xs);
}

.detected-scale {
  padding: 0.75rem;
  background: var(--color-gray-light);
  border: 1px solid #bdc3c7;
  border-radius: var(--radius-sm);
  margin-top: var(--spacing-sm);
  font-weight: bold;
  color: var(--color-secondary);
  text-align: center;
}

.calibration-box {
  padding: 0.75rem;
  background: #e3f2fd;
  border: 1px solid #90caf9;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  color: #1565c0;
  margin-bottom: var(--spacing-sm);
}

#calibrationMeasure label {
  display: block;
  margin-bottom: var(--spacing-sm);
}

#calibrationMeasure input,
#calibrationMeasure select {
  width: 100%;
  padding: var(--spacing-sm);
  border: 1px solid var(--color-gray-border);
  border-radius: var(--radius-sm);
  margin-top: var(--spacing-xs);
}

#calibrationMeasure select {
  margin-top: var(--spacing-sm);
}

.furniture-categories {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.category-btn {
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--color-gray-border);
  background: white;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.85rem;
  transition: all var(--transition-normal);
}

.category-btn:hover {
  background: var(--color-gray-light);
}

.category-btn.active {
  background: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

.furniture-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-sm);
}

.furniture-item {
  padding: 0.8rem;
  border: 1px solid var(--color-gray-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-normal);
  background: white;
}

.furniture-item:hover {
  background: var(--color-gray-light);
  transform: translateX(4px);
}

.furniture-item h4 {
  font-size: 0.95rem;
  margin-bottom: var(--spacing-xs);
}

.furniture-item p {
  font-size: 0.8rem;
  color: var(--color-gray);
}

.furniture-properties label {
  display: block;
  margin-bottom: var(--spacing-md);
}

.furniture-properties input {
  width: 100%;
  padding: var(--spacing-sm);
  border: 1px solid var(--color-gray-border);
  border-radius: var(--radius-sm);
  margin-top: var(--spacing-xs);
}

.canvas-container {
  flex: 1;
  position: relative;
  overflow: hidden;
  background: var(--color-gray-light);
  width: 100%;
  max-width: 100%;
}

.canvas-controls {
  position: absolute;
  bottom: var(--spacing-md);
  right: var(--spacing-md);
  display: flex;
  gap: var(--spacing-sm);
  align-items: center;
  background: white;
  padding: var(--spacing-sm);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-md);
  z-index: 10;
}

.btn-icon {
  width: 36px;
  height: 36px;
  border: 1px solid var(--color-gray-border);
  background: white;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-normal);
}

.btn-icon:hover {
  background: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

#zoomLevel {
  font-size: 0.9rem;
  color: var(--color-gray);
  min-width: 50px;
  text-align: center;
}

.scale-separator {
  font-size: 0.9rem;
  color: #bdc3c7;
  margin: 0 var(--spacing-sm);
}

.scale-info {
  font-size: 0.85rem;
  color: var(--color-gray);
  padding: var(--spacing-xs) var(--spacing-sm);
  background: var(--color-gray-light);
  border-radius: var(--radius-sm);
}

.canvas-wrapper {
  width: 100%;
  height: 100%;
  overflow: auto;
  cursor: grab;
  position: relative;
}

.canvas-wrapper:active {
  cursor: grabbing;
}

.upload-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(245, 245, 245, 0.95);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 10;
}

.upload-box {
  text-align: center;
  padding: 3rem;
  background: white;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
}

.upload-box h2 {
  margin-bottom: var(--spacing-md);
  color: var(--color-secondary);
}

.upload-box p {
  margin-bottom: var(--spacing-md);
  color: var(--color-gray);
}

.project-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem;
  margin-bottom: var(--spacing-sm);
  background: #f8f9fa;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition-normal);
}

.project-item:hover {
  background: #e9ecef;
}

.project-item-info {
  flex: 1;
}

.project-item-name {
  font-weight: bold;
  color: var(--color-secondary);
}

.project-item-date {
  font-size: 0.85rem;
  color: var(--color-gray);
}

.project-item-delete {
  background: var(--color-danger);
  color: white;
  border: none;
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.9rem;
}

.project-item-delete:hover {
  background: var(--color-danger-dark);
}

.calibration-panel {
  position: absolute;
  bottom: 5rem;
  right: var(--spacing-md);
  background: white;
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  z-index: 11;
  min-width: 280px;
}

.calibration-panel h4 {
  margin: 0 0 var(--spacing-sm) 0;
  color: var(--color-secondary);
  font-size: 1rem;
}

.calibration-instructions {
  font-size: 0.85rem;
  color: var(--color-gray);
  margin-bottom: 0.75rem;
  line-height: 1.5;
}

.calibration-panel label {
  display: block;
  font-size: 0.9rem;
  margin-bottom: var(--spacing-sm);
}

.calibration-panel input,
.calibration-panel select {
  width: 100%;
  padding: 0.4rem;
  margin-top: var(--spacing-xs);
  border: 1px solid var(--color-gray-border);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
}

/* Crop Panel */
.crop-panel {
  position: absolute;
  bottom: 5rem;
  right: var(--spacing-md);
  background: white;
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  z-index: 11;
  min-width: 280px;
}

.crop-panel h4 {
  margin: 0 0 var(--spacing-sm) 0;
  color: var(--color-secondary);
  font-size: 1rem;
}

.crop-instructions {
  font-size: 0.85rem;
  color: var(--color-gray);
  margin-bottom: 0.75rem;
  line-height: 1.5;
}

.crop-controls {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-sm);
}

#cropDimensions {
  font-weight: bold;
  color: var(--color-primary);
}

#mainCanvas {
  display: block;
  background: white;
  box-shadow: var(--shadow-md);
}

/* Snapshot Graph Visualization in Header */
.snapshot-graph-header {
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, 0.1);
  padding: var(--spacing-sm);
  border-radius: var(--radius-sm);
  max-width: 280px;
  max-height: 48px;
  overflow-x: auto;
  overflow-y: hidden;
  gap: var(--spacing-sm);
  transition: all var(--transition-slow) ease;
  transform: scale(0.7);
  transform-origin: left center;
  margin: calc(-1 * var(--spacing-sm));
}

.snapshot-graph-header:hover {
  max-width: 600px;
  max-height: 200px;
  background: rgba(255, 255, 255, 0.15);
  box-shadow: var(--shadow-lg);
  z-index: 1000;
  transform: scale(1);
  margin: 0;
  padding: var(--spacing-md);
}

.snapshot-graph-header:empty {
  display: none;
}

.snapshot-graph-container {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-xs);
}

.snapshot-column {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  position: relative;
}

.snapshot-node {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--color-primary);
  border: 2px solid var(--color-primary-dark);
  cursor: pointer;
  transition: all var(--transition-normal);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 0.6rem;
  font-weight: bold;
  flex-shrink: 0;
}

.snapshot-node:hover {
  transform: scale(1.3);
  z-index: 10;
  box-shadow: var(--shadow-lg);
}

.snapshot-node.current {
  background: var(--color-danger);
  border-color: var(--color-danger-dark);
  box-shadow:
    0 0 20px rgba(231, 76, 60, 0.9),
    0 0 40px rgba(231, 76, 60, 0.5);
  animation: pulse-current 2s ease-in-out infinite;
}

@keyframes pulse-current {
  0%,
  100% {
    transform: scale(1);
    box-shadow:
      0 0 20px rgba(231, 76, 60, 0.9),
      0 0 40px rgba(231, 76, 60, 0.5);
  }
  50% {
    transform: scale(1.1);
    box-shadow:
      0 0 25px rgba(231, 76, 60, 1),
      0 0 50px rgba(231, 76, 60, 0.6);
  }
}

.snapshot-node.root {
  background: var(--color-success);
  border-color: var(--color-success-dark);
}

.snapshot-node.unsaved-hint {
  background: rgba(241, 196, 15, 0.9);
  border-color: var(--color-warning);
  animation: pulse-unsaved 1.5s ease-in-out infinite;
  cursor: default;
}

@keyframes pulse-unsaved {
  0%,
  100% {
    transform: scale(1);
    opacity: 0.8;
  }
  50% {
    transform: scale(1.15);
    opacity: 1;
  }
}

.snapshot-tooltip {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(44, 62, 80, 0.95);
  color: white;
  padding: var(--spacing-sm) 0.75rem;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  white-space: nowrap;
  pointer-events: none;
  opacity: 0;
  transition: opacity var(--transition-normal);
  margin-bottom: var(--spacing-sm);
  z-index: 100;
}

.snapshot-node:hover .snapshot-tooltip {
  opacity: 1;
}

.snapshot-delete-btn {
  position: absolute;
  top: -6px;
  right: -6px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-danger);
  color: white;
  border: 2px solid white;
  font-size: 10px;
  line-height: 12px;
  text-align: center;
  cursor: pointer;
  opacity: 0;
  transition: opacity var(--transition-normal);
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
}

.snapshot-node:hover .snapshot-delete-btn {
  opacity: 1;
}

.snapshot-delete-btn:hover {
  background: var(--color-danger-dark);
  transform: scale(1.1);
}

.snapshot-connection {
  position: absolute;
  height: 2px;
  background: var(--color-primary);
  top: 50%;
  transform: translateY(-50%);
}

.snapshot-branch-line {
  position: absolute;
  width: 2px;
  background: var(--color-primary);
  left: 50%;
  transform: translateX(-50%);
}

/* Project Name Display */
.project-name-display {
  max-width: 200px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  padding: var(--spacing-sm) var(--spacing-md);
}

/* Hidden Panel */
.panel-hidden {
  display: none;
}

/* Property Labels - Hidden State */
.property-label-hidden {
  display: none;
}

/* Project Name Input */
.project-name-input {
  width: 100%;
  padding: 0.75rem;
  margin-bottom: var(--spacing-md);
  border: 1px solid var(--color-gray-border);
  border-radius: var(--radius-sm);
  font-size: 1rem;
}

/* Upload Button Sized */
.upload-btn-sized {
  font-size: 1.2rem;
  padding: 1rem 2rem;
  width: 100%;
}

/* Project List Section */
.project-list-section {
  margin-top: var(--spacing-xl);
  padding-top: var(--spacing-xl);
  border-top: 1px solid var(--color-gray-border);
}

.project-list-section h3 {
  margin-bottom: var(--spacing-md);
  font-size: 1.1rem;
}

.project-list-container {
  max-height: 300px;
  overflow-y: auto;
}

/* Calibration Controls */
.calibration-controls {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-sm);
}

.calibration-controls .btn {
  flex: 1;
}

/* Language Selector */
.language-selector {
  background: rgba(255, 255, 255, 0.1);
  color: white;
  border: 1px solid rgba(255, 255, 255, 0.2);
  padding: 0.5rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.9rem;
  transition: background var(--transition-normal);
}

.language-selector:hover {
  background: rgba(255, 255, 255, 0.15);
}

.language-selector option {
  background: var(--color-secondary);
  color: white;
}