:root {
  --bg: #0d1117;
  --panel: #161b22;
  --panel-border: #30363d;
  --text: #c9d1d9;
  --muted: #8b949e;
  --primary: #4493f8;
  --accent: #238636;
  --danger: #f85149;
  --glass: rgba(255, 255, 255, 0.03);
  --shadow: 0 20px 60px rgba(0, 0, 0, 0.45);
  --bar-default: linear-gradient(180deg, #2b3138, #1f252c);
  --bar-compare: #58a6ff;
  --bar-swap: #d29922;
  --bar-sorted: #2ea043;
  --bar-pivot: #db61a2;
  --bar-merge: #7ee787;
}

body.theme-light {
  --bg: #f5f7fb;
  --panel: rgba(255, 255, 255, 0.75);
  --panel-border: rgba(0, 0, 0, 0.05);
  --text: #1b2430;
  --muted: #52607a;
  --primary: #5b6cfb;
  --accent: #00c4a7;
  --danger: #ff4f70;
  --glass: rgba(255, 255, 255, 0.75);
  --shadow: 0 10px 45px rgba(18, 38, 68, 0.2);
  --bar-default: linear-gradient(180deg, #d8dff3, #b5c0e9);
}

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

body {
  margin: 0;
  font-family: 'Space Grotesk', 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  padding: 24px;
}

.app-shell {
  max-width: 1200px;
  margin: 0 auto;
}

.hero {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 12px;
  color: var(--accent);
  margin: 0 0 6px;
}

h1 {
  margin: 0;
  font-size: 32px;
  letter-spacing: -0.02em;
}

.subtitle {
  margin: 6px 0 0;
  color: var(--muted);
  max-width: 680px;
}

.layout {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 18px;
}

.control-panel {
  position: sticky;
  top: 16px;
  align-self: start;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 18px;
  padding: 16px;
  backdrop-filter: blur(6px);
  box-shadow: var(--shadow);
  transition: max-height 0.4s ease, opacity 0.3s ease;
}

.control-panel.collapsed {
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  padding: 0 16px;
  margin: 0;
}

.panel-section {
  border-bottom: 1px solid var(--panel-border);
  padding-bottom: 14px;
  margin-bottom: 14px;
}

.panel-section:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

.info-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.section-header h2 {
  margin: 0;
  font-size: 16px;
}

.badge {
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--panel-border);
  color: var(--muted);
  font-size: 12px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 12px;
  font-size: 14px;
}

.field-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 6px;
}

.value-pill {
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--panel-border);
  color: var(--text);
  font-size: 12px;
}

.value-pill.ghost {
  background: transparent;
  border-style: dashed;
}

select,
input[type="range"] {
  width: 100%;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--panel-border);
  border-radius: 12px;
  padding: 10px;
  color: var(--text);
  outline: none;
  transition: border 0.2s ease, transform 0.2s ease;
}

select:focus,
input[type="range"]:focus {
  border-color: var(--primary);
  transform: translateY(-1px);
}

input[type="range"] {
  accent-color: var(--primary);
}

.button-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 10px;
  margin: 10px 0;
}

button {
  cursor: pointer;
  border: none;
  border-radius: 12px;
  padding: 11px 12px;
  font-weight: 600;
  color: var(--text);
  background: rgba(255, 255, 255, 0.05);
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease;
}

button:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.2);
}

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

button.primary {
  background: var(--primary);
  color: #0c1625;
}

button.accent {
  background: var(--accent);
  color: #f1f7f3;
}

button.ghost {
  background: rgba(255, 255, 255, 0.03);
  border: 1px dashed var(--panel-border);
}

button.danger {
  color: var(--danger);
  border-color: rgba(255, 95, 122, 0.5);
}

.ghost-button {
  background: transparent;
  border: 1px solid var(--panel-border);
  padding: 10px 14px;
  font-size: 14px;
}

.toggle-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.toggle {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--panel-border);
}

.toggle input {
  display: none;
}

.toggle .slider {
  width: 44px;
  height: 22px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
  position: relative;
  transition: background 0.2s ease;
}

.toggle .slider::after {
  content: '';
  position: absolute;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--text);
  top: 2px;
  left: 2px;
  transition: transform 0.2s ease;
}

.toggle input:checked + .slider {
  background: var(--primary);
}

.toggle input:checked + .slider::after {
  transform: translateX(22px);
}

.toggle .label {
  color: var(--muted);
  font-size: 13px;
}

.legend-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(110px, 1fr));
  gap: 8px;
}

.pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 10px;
  border-radius: 999px;
  font-size: 12px;
  border: 1px solid var(--panel-border);
}

.pill.default {
  background: rgba(255, 255, 255, 0.03);
}

.pill.compare {
  background: var(--bar-compare);
  color: #041118;
}

.pill.swap {
  background: var(--bar-swap);
  color: #1f1300;
}

.pill.sorted {
  background: var(--bar-sorted);
  color: #0a160e;
}

.pill.pivot {
  background: var(--bar-pivot);
  color: #180513;
}

.pill.merge {
  background: var(--bar-merge);
  color: #0a1335;
}

.info-text {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.6;
  margin-bottom: 12px;
}

.info-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.info-grid .metric {
  margin: 2px 0 0;
  font-weight: 600;
}

.muted {
  color: var(--muted);
  font-size: 12px;
}

.visual {
  position: relative;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 18px;
  height: 600px;
  box-shadow: var(--shadow);
  overflow: hidden;
  backdrop-filter: blur(10px);
  padding: 20px 16px 16px;
}

.bars {
  display: flex;
  align-items: flex-end;
  justify-content: center;
  gap: 4px;
  height: 100%;
}

.bar {
  flex: 1;
  min-width: 4px;
  max-width: 24px;
  border-radius: 8px 8px 4px 4px;
  background: var(--bar-default);
  position: relative;
  transition: height 0.2s ease, transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.bar small {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translate(-50%, -6px);
  color: var(--muted);
  font-size: 10px;
  opacity: 0.9;
}

.bar.compare {
  background: var(--bar-compare);
  box-shadow: 0 0 20px rgba(102, 227, 255, 0.5);
}

.bar.swap {
  background: var(--bar-swap);
  box-shadow: 0 0 20px rgba(255, 179, 71, 0.5);
}

.bar.sorted {
  background: var(--bar-sorted);
  box-shadow: 0 0 20px rgba(124, 255, 173, 0.35);
}

.bar.pivot {
  background: var(--bar-pivot);
  box-shadow: 0 0 20px rgba(255, 123, 218, 0.4);
}

.bar.merge-write {
  background: var(--bar-merge);
  box-shadow: 0 0 20px rgba(108, 146, 255, 0.45);
}

.bar:hover {
  transform: translateY(-2px);
}

.stats-overlay {
  position: absolute;
  top: 14px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 12px;
  background: rgba(0, 0, 0, 0.35);
  padding: 12px 16px;
  border-radius: 12px;
  border: 1px solid var(--panel-border);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow);
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 4px;
}

.stat span:last-child {
  font-weight: 700;
}

.footer {
  margin-top: 14px;
  color: var(--muted);
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 10px;
  text-align: right;
}

.footer p {
  margin: 0;
}

.kbd-hint {
  font-size: 12px;
}

.icon-button {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1px solid var(--panel-border);
  background: rgba(255, 255, 255, 0.05);
  color: var(--text);
  font-weight: 700;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0;
}

.icon-button:hover {
  background: rgba(255, 255, 255, 0.1);
}

.info-modal {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(4px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
  z-index: 10;
}

.info-modal.open {
  opacity: 1;
  pointer-events: all;
}

.info-dialog {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  border-radius: 14px;
  padding: 16px 18px;
  max-width: 440px;
  width: 92%;
  box-shadow: var(--shadow);
}

.info-dialog-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}

.info-dialog h3 {
  margin: 0;
}

.info-body {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

@media (max-width: 1024px) {
  .layout {
    grid-template-columns: 1fr;
  }

  .control-panel {
    position: relative;
    max-height: none;
  }
}

@media (max-width: 680px) {
  body {
    padding: 16px;
  }

  .hero {
    flex-direction: column;
    align-items: flex-start;
  }

  .bars {
    gap: 3px;
  }

  .bar {
    width: 10px;
  }

  .visual {
    height: 440px;
  }
}