/* ================================================================
   Cache Access Pattern Visualizer — Styles
   ================================================================ */

:root {
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-tertiary: #21262d;
  --bg-elevated: #1c2128;
  --border: #30363d;
  --border-light: #3d444d;
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --text-muted: #484f58;
  --accent: #58a6ff;
  --accent-glow: rgba(88, 166, 255, 0.25);
  --green: #3fb950;
  --green-bg: rgba(63, 185, 80, 0.15);
  --green-glow: rgba(63, 185, 80, 0.4);
  --red: #f85149;
  --red-bg: rgba(248, 81, 73, 0.15);
  --red-glow: rgba(248, 81, 73, 0.4);
  --orange: #d29922;
  --orange-bg: rgba(210, 153, 34, 0.15);
  --purple: #bc8cff;
  --purple-bg: rgba(188, 140, 255, 0.15);
  --yellow: #e3b341;
  --radius: 8px;
  --radius-sm: 4px;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --font-sans: 'Inter', -apple-system, sans-serif;
  --transition: 150ms ease;
}

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

html {
  font-size: 14px;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  overflow: hidden;
}

/* ── Header ──────────────────────────────────────────── */

.app-header {
  padding: 14px 24px 10px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.app-header h1 {
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--accent), var(--purple));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 0.78rem;
  margin-top: 1px;
}

/* ── Three-Panel Layout ──────────────────────────────── */

.app-layout {
  display: grid;
  grid-template-columns: 280px 1fr 240px;
  gap: 0;
  height: calc(100vh - 62px);
}

.panel {
  padding: 12px;
  overflow-y: auto;
  border-right: 1px solid var(--border);
}

.panel:last-child {
  border-right: none;
}

.panel-title {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ── Controls Panel ──────────────────────────────────── */

.control-group {
  margin-bottom: 14px;
}

.group-label {
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.input-grid {
  display: grid;
  gap: 5px;
}

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

.cache-grid-inputs {
  grid-template-columns: 1fr 1fr;
}

.input-grid label {
  display: flex;
  flex-direction: column;
  gap: 2px;
  font-size: 0.68rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.input-grid input[type="number"] {
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  padding: 5px 7px;
  width: 100%;
  outline: none;
  transition: border-color var(--transition);
}

.input-grid input[type="number"]:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-glow);
}

#code-editor {
  width: 100%;
  height: 140px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  line-height: 1.5;
  padding: 8px 10px;
  resize: vertical;
  outline: none;
  tab-size: 2;
  transition: border-color var(--transition);
}

#code-editor:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-glow);
}

.speed-control {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 8px;
}

.speed-label {
  font-size: 0.68rem;
  color: var(--text-secondary);
  font-weight: 500;
  white-space: nowrap;
}

.speed-val {
  font-size: 0.65rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  white-space: nowrap;
  min-width: 42px;
}

#speed-slider {
  flex: 1;
  accent-color: var(--accent);
  height: 4px;
}

.anim-buttons {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5px;
}

.btn {
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 0.72rem;
  font-weight: 500;
  padding: 6px 8px;
  cursor: pointer;
  transition: all var(--transition);
  user-select: none;
}

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

.btn:active {
  transform: scale(0.97);
}

.btn-sm {
  padding: 3px 8px;
  font-size: 0.72rem;
  font-weight: 600;
}

.btn-primary {
  background: linear-gradient(135deg, rgba(88, 166, 255, 0.2), rgba(188, 140, 255, 0.2));
  border-color: var(--accent);
  color: var(--accent);
}

.btn-primary:hover {
  background: linear-gradient(135deg, rgba(88, 166, 255, 0.35), rgba(188, 140, 255, 0.35));
}

.btn-danger {
  color: var(--red);
  border-color: rgba(248, 81, 73, 0.3);
}

.btn-danger:hover {
  background: var(--red-bg);
}

/* ── Stats ───────────────────────────────────────────── */

.stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5px;
  margin-bottom: 10px;
}

.stat-card {
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 7px 9px;
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.stat-value {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
}

.stat-label {
  font-size: 0.6rem;
  font-weight: 500;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.stat-hit .stat-value {
  color: var(--green);
}

.stat-miss .stat-value {
  color: var(--red);
}

.progress-container {
  margin-top: 2px;
}

.progress-label {
  display: flex;
  justify-content: space-between;
  font-size: 0.65rem;
  color: var(--text-muted);
  margin-bottom: 3px;
}

.progress-bar-bg {
  height: 5px;
  background: var(--bg-tertiary);
  border-radius: 3px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--purple));
  border-radius: 3px;
  transition: width 100ms ease;
}

/* ── Center Panel — Canvas Areas ─────────────────────── */

.panel-center {
  display: flex;
  flex-direction: column;
  gap: 0;
  padding: 0;
  overflow: hidden;
}

.canvas-section {
  display: flex;
  flex-direction: column;
  min-height: 60px;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
}

.canvas-section:last-child {
  border-bottom: none;
}

#array-section {
  border-top: none;
}

.canvas-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 12px 4px;
  flex-shrink: 0;
}

.canvas-header .panel-title {
  margin-bottom: 0;
}

.zoom-controls {
  display: flex;
  align-items: center;
  gap: 4px;
}

.zoom-label {
  font-size: 0.65rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  min-width: 36px;
  text-align: right;
}

.cache-info {
  font-size: 0.65rem;
  font-weight: 400;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.canvas-wrapper {
  flex: 1;
  overflow: hidden;
  position: relative;
  cursor: grab;
  background: var(--bg-primary);
}

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

.canvas-wrapper canvas {
  position: absolute;
  top: 0;
  left: 0;
  image-rendering: pixelated;
}

/* Resize Handle */

.resize-handle {
  height: 8px;
  flex-shrink: 0;
  cursor: row-resize;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  transition: background 150ms ease;
  user-select: none;
}

.resize-handle:hover,
.resize-handle.active {
  background: var(--bg-tertiary);
}

.resize-grip {
  width: 40px;
  height: 3px;
  border-radius: 2px;
  background: var(--border-light);
}

/* ── Right Panel — Index Viz + Legend ─────────────────── */

.index-viz {
  margin-bottom: 12px;
}

.index-dim {
  margin-bottom: 8px;
}

.index-dim-label {
  font-size: 0.65rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 3px;
  display: flex;
  justify-content: space-between;
}

.index-dim-label .idx-value {
  font-family: var(--font-mono);
  color: var(--accent);
}

.index-bar {
  display: flex;
  gap: 1px;
  flex-wrap: wrap;
}

.index-cell {
  width: 12px;
  height: 12px;
  border-radius: 2px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  transition: background 180ms ease, border-color 180ms ease;
}

.index-cell.active {
  background: var(--accent);
  border-color: var(--accent);
  box-shadow: 0 0 5px var(--accent-glow);
}

/* Legend */

.legend {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.68rem;
  color: var(--text-secondary);
}

.legend-swatch {
  width: 14px;
  height: 14px;
  border-radius: 3px;
  flex-shrink: 0;
}

.legend-hit {
  background: #3fb950;
}

.legend-miss {
  background: #f85149;
}

.legend-occupied {
  background: #2d333b;
  border: 1px solid #58a6ff;
}

.legend-empty {
  background: #161b22;
  border: 1px solid #30363d;
}

.legend-hot {
  background: #f97316;
}

.legend-cold {
  background: #1e293b;
  border: 1px solid #334155;
}

.legend-touched {
  background: #58a6ff;
}

/* ── Scrollbar ───────────────────────────────────────── */

::-webkit-scrollbar {
  width: 5px;
  height: 5px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--border-light);
}

/* ── Responsive ──────────────────────────────────────── */

@media (max-width: 1100px) {
  .app-layout {
    grid-template-columns: 240px 1fr 200px;
  }
}

@media (max-width: 860px) {
  .app-layout {
    grid-template-columns: 1fr;
    height: auto;
  }

  body {
    overflow: auto;
  }

  .panel {
    border-right: none;
    border-bottom: 1px solid var(--border);
  }

  .panel-center {
    min-height: 500px;
  }
}