:root {
  --primary-color: #2563eb;
  --secondary-color: #dc2626;
  --success-color: #16a34a;
  --warning-color: #f59e0b;
  --bg-color: #f8fafc;
  --card-bg: #ffffff;
  --text-color: #1e293b;
  --border-color: #e2e8f0;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

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

body {
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu,
    sans-serif;
  background: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
  padding: 20px;
}

.container {
  max-width: 1400px;
  margin: 0 auto;
}

header {
  text-align: center;
  margin-bottom: 30px;
  padding: 20px;
  background: var(--card-bg);
  border-radius: 12px;
  box-shadow: var(--shadow);
}

header h1 {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: 10px;
}

.subtitle {
  color: #64748b;
  font-size: 1rem;
}

/* Controls Section */
.controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
  margin-bottom: 30px;
}

.control-group {
  background: var(--card-bg);
  padding: 20px;
  border-radius: 12px;
  box-shadow: var(--shadow);
}

.control-group h3 {
  font-size: 1.1rem;
  margin-bottom: 15px;
  color: var(--text-color);
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 8px;
}

.control-row {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 15px;
}

.control-row label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.9rem;
  gap: 10px;
  width: 100%;
  min-width: 0;
}

.control-row label > span:first-child {
  flex: 1;
  min-width: 120px;
}

.control-row label > span:last-child {
  flex: 0 0 40px;
  min-width: 40px;
  text-align: right;
  font-weight: 600;
  color: var(--primary-color);
}

.control-row select,
.control-row input[type="range"] {
  flex: 1;
}

.control-row select {
  padding: 8px 12px;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  background: white;
  font-size: 0.9rem;
  cursor: pointer;
  transition: border-color 0.2s;
}

.control-row select:hover {
  border-color: var(--primary-color);
}

.control-row input[type="range"] {
  height: 6px;
  background: var(--border-color);
  border-radius: 3px;
  outline: none;
  cursor: pointer;
}

.control-row input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  background: var(--primary-color);
  border-radius: 50%;
  cursor: pointer;
}

.control-row label > input[type="range"] {
  min-width: 0;
}

.mode-btn {
  padding: 10px 16px;
  border: 2px solid var(--border-color);
  background: white;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: all 0.2s;
  font-weight: 500;
  color: var(--text-color);
}

.mode-btn:hover {
  border-color: var(--primary-color);
  background: #eff6ff;
  color: var(--primary-color);
}

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

button {
  padding: 10px 16px;
  border: none;
  border-radius: 8px;
  background: var(--primary-color);
  color: white;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.2s;
}

button:hover {
  background: #1d4ed8;
  transform: translateY(-1px);
  box-shadow: var(--shadow);
}

button:active {
  transform: translateY(0);
}

#resetBtn {
  background: var(--secondary-color);
}

#resetBtn:hover {
  background: #b91c1c;
}

/* Visualization Section */
.visualization {
  display: grid;
  gap: 25px;
  margin-bottom: 30px;
}

.plot-container {
  background: var(--card-bg);
  padding: 20px;
  border-radius: 12px;
  box-shadow: var(--shadow);
}

.plot-container h3 {
  font-size: 1.1rem;
  margin-bottom: 15px;
  color: var(--text-color);
}

.plot-container canvas {
  width: 100%;
  height: auto;
  display: block;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: white;
}

#signalCanvas {
  height: 250px;
}

#scalogramCanvas {
  height: 300px;
}

.colorbar {
  margin-top: 10px;
  display: flex;
  align-items: center;
  gap: 10px;
}

#colorbarCanvas {
  width: 100%;
  height: 30px;
  border: 1px solid var(--border-color);
  border-radius: 4px;
}

.plot-info {
  display: flex;
  flex-wrap: wrap;
  gap: 15px;
  margin-top: 10px;
  font-size: 0.85rem;
  color: #64748b;
}

.plot-info span {
  display: flex;
  align-items: center;
  gap: 6px;
}

.plot-info span::before {
  content: "";
  width: 12px;
  height: 12px;
  border-radius: 2px;
}

.plot-info span:nth-child(1)::before {
  background: #2563eb;
}

.plot-info span:nth-child(2)::before {
  background: #dc2626;
}

.plot-info span:nth-child(3)::before {
  background: #16a34a;
}

/* DWT Tree */
.dwt-tree {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.dwt-level {
  background: #f1f5f9;
  padding: 15px;
  border-radius: 8px;
  margin-bottom: 10px;
}

.dwt-level h4 {
  font-size: 0.95rem;
  margin-bottom: 10px;
  color: var(--text-color);
}

.dwt-coeffs {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 15px;
}

.coeff-plot {
  background: white;
  padding: 10px;
  border-radius: 6px;
  border: 1px solid var(--border-color);
}

.coeff-plot h5 {
  font-size: 0.85rem;
  margin-bottom: 8px;
  color: #64748b;
}

.coeff-plot canvas {
  width: 100%;
  height: 80px;
  border: none;
  border-radius: 4px;
}

/* Comparison Grid */
.compare-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.compare-grid > div {
  background: #f1f5f9;
  padding: 15px;
  border-radius: 8px;
}

.compare-grid h4 {
  font-size: 0.95rem;
  margin-bottom: 10px;
  color: var(--text-color);
}

.compare-grid canvas {
  width: 100%;
  height: 200px;
}

/* Reconstruction Stats */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 15px;
  margin-top: 15px;
}

.stat-box {
  background: #f1f5f9;
  padding: 12px;
  border-radius: 8px;
  text-align: center;
}

.stat-box .label {
  font-size: 0.8rem;
  color: #64748b;
  margin-bottom: 5px;
}

.stat-box .value {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--primary-color);
}

/* Custom Drawing */
.custom-draw {
  background: var(--card-bg);
  padding: 20px;
  border-radius: 12px;
  box-shadow: var(--shadow);
  margin-bottom: 30px;
}

.custom-draw h3 {
  font-size: 1.1rem;
  margin-bottom: 15px;
}

#customDrawCanvas {
  width: 100%;
  height: 200px;
  border: 2px dashed var(--border-color);
  border-radius: 8px;
  cursor: crosshair;
  background: white;
}

.custom-draw p {
  margin-top: 10px;
  font-size: 0.9rem;
  color: #64748b;
}

.custom-draw button {
  margin-top: 15px;
}

/* Educational Content */
.educational {
  background: var(--card-bg);
  padding: 25px;
  border-radius: 12px;
  box-shadow: var(--shadow);
  margin-bottom: 30px;
}

.tabs {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 10px 20px;
  border: 2px solid var(--border-color);
  background: white;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.2s;
  color: var(--text-color);
}

.tab-btn:hover {
  border-color: var(--primary-color);
  background: #eff6ff;
  color: var(--primary-color);
}

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

.tab-content {
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.tab-content h4 {
  font-size: 1rem;
  color: var(--text-color);
  margin: 20px 0 10px 0;
}

.formula {
  background: #f8fafc;
  padding: 15px;
  border-radius: 8px;
  border-left: 4px solid var(--primary-color);
  font-size: 1.1rem;
  overflow-x: auto;
}

.tab-content p {
  color: #64748b;
  margin: 10px 0;
  line-height: 1.7;
}

.concept-card,
.application-card {
  background: #f8fafc;
  padding: 15px;
  border-radius: 8px;
  margin-bottom: 15px;
  border-left: 4px solid var(--primary-color);
}

.concept-card h4,
.application-card h4 {
  margin: 0 0 10px 0;
  color: var(--text-color);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 15px;
}

.comparison-table th,
.comparison-table td {
  padding: 12px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.comparison-table th {
  background: #f1f5f9;
  font-weight: 600;
  color: var(--text-color);
}

.comparison-table tr:hover {
  background: #f8fafc;
}

/* Stats Panel */
.stats-panel {
  background: var(--card-bg);
  padding: 20px;
  border-radius: 12px;
  box-shadow: var(--shadow);
  margin-bottom: 30px;
}

.stats-panel h3 {
  font-size: 1.1rem;
  margin-bottom: 15px;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 15px;
}

.stat-item {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 12px;
  background: #f1f5f9;
  border-radius: 8px;
}

.stat-item span:first-child {
  font-size: 0.8rem;
  color: #64748b;
}

.stat-item span:last-child {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--primary-color);
}

/* Wavelet Info Panel */
.wavelet-info {
  background: var(--card-bg);
  padding: 20px;
  border-radius: 12px;
  box-shadow: var(--shadow);
  margin-bottom: 30px;
}

.wavelet-info h3 {
  font-size: 1.1rem;
  margin-bottom: 15px;
}

.wavelet-properties {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 15px;
}

.wavelet-prop {
  background: #f1f5f9;
  padding: 12px;
  border-radius: 8px;
}

.wavelet-prop .label {
  font-size: 0.8rem;
  color: #64748b;
  margin-bottom: 5px;
}

.wavelet-prop .value {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-color);
}

/* Responsive Design */
@media (max-width: 768px) {
  body {
    padding: 10px;
  }

  header h1 {
    font-size: 1.5rem;
  }

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

  .control-row {
    flex-direction: column;
  }

  .control-row label {
    flex-direction: column;
    align-items: flex-start;
    width: 100%;
  }

  .control-row label span {
    min-width: 0;
    width: 100%;
  }

  .control-row select,
  .control-row input[type="range"] {
    width: 100%;
  }

  .mode-btn,
  #animateBtn,
  #stepBtn,
  #resetBtn,
  #applyCustomDraw,
  #clearCustomDraw {
    width: 100%;
  }

  #signalCanvas {
    height: 200px;
  }

  #scalogramCanvas {
    height: 240px;
  }

  .compare-grid canvas {
    height: 180px;
  }

  #customDrawCanvas {
    height: 180px;
  }

  .plot-info {
    flex-direction: column;
    gap: 8px;
  }

  .stats-grid,
  .wavelet-properties {
    grid-template-columns: 1fr 1fr;
  }

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

  .tabs {
    flex-direction: column;
  }

  .tab-btn {
    width: 100%;
  }
}

@media (max-width: 480px) {
  header h1 {
    font-size: 1.2rem;
  }

  .stats-grid,
  .wavelet-properties {
    grid-template-columns: 1fr;
  }

  #signalCanvas {
    height: 180px;
  }

  #scalogramCanvas {
    height: 220px;
  }

  #customDrawCanvas {
    height: 160px;
  }
}

/* Utility Classes */
.hidden {
  display: none !important;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Loading State */
.loading {
  opacity: 0.6;
  pointer-events: none;
}

/* Tooltip */
.tooltip {
  position: relative;
  display: inline-block;
}

.tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  background: #1e293b;
  color: white;
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 0.8rem;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s;
}

.tooltip:hover::after {
  opacity: 1;
}