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

:root {
  --bg:          #08090d;
  --bg-card:     #0d0f16;
  --bg-elevated: #141720;
  --text:        #e2e4ea;
  --text-dim:    #7a7f94;
  --text-muted:  #4a4f62;
  --accent:      #4fc3f7;
  --accent-dim:  rgba(79, 195, 247, 0.10);
  --accent2:     #ff8a65;
  --border:      #1e2130;
  --bit-sign:    #ef5350;
  --bit-exp:     #42a5f5;
  --bit-mant:    #66bb6a;
  --radius:      10px;
  --radius-sm:   6px;
  --content-max: 1440px;
  --pad:         40px;
  --font-mono:   'SF Mono', 'Fira Code', 'Cascadia Code', 'Courier New', monospace;
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  line-height: 1.6;
  overflow-x: hidden;
}

/* Accent top bar */
body::before {
  content: '';
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent2), var(--accent));
  z-index: 1000;
}

/* ── Loading Overlay ──────────────────────────────────────────────── */
#loading-overlay {
  position: fixed;
  inset: 0;
  background: rgba(8, 9, 13, 0.96);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  z-index: 500;
  transition: opacity 0.5s;
}
#loading-overlay.hidden { opacity: 0; pointer-events: none; }

.spinner {
  width: 36px; height: 36px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

#loading-overlay p {
  font-size: 0.85rem;
  color: var(--text-dim);
}

/* ── Header ───────────────────────────────────────────────────────── */
#page-header {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 32px var(--pad) 16px;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 20px;
}

#page-header h1 {
  font-size: clamp(1.15rem, 2vw, 1.55rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.3;
}

.subtitle {
  font-size: 0.82rem;
  color: var(--text-dim);
  margin-top: 6px;
}

.abstract-toggle {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 7px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  cursor: pointer;
  font-family: inherit;
  white-space: nowrap;
  transition: all 0.2s;
  flex-shrink: 0;
}
.abstract-toggle:hover {
  border-color: var(--accent);
  color: var(--text);
}

/* ── Abstract (collapsible) ───────────────────────────────────────── */
#description {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--pad);
  overflow: hidden;
  max-height: 300px;
  transition: max-height 0.4s ease;
}
#description.collapsed { max-height: 0; }

.abstract-inner p {
  padding-bottom: 16px;
  text-align: justify;
  font-size: 0.88rem;
  color: var(--text-dim);
  line-height: 1.85;
}

.abstract-inner p:last-child {
  border-bottom: 1px solid var(--border);
  padding-bottom: 20px;
}

.formula-note {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.formula-line {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--text);
  flex-wrap: wrap;
}

.formula-label {
  min-width: 140px;
  color: var(--text-dim);
  font-size: 0.75rem;
  text-align: right;
  flex-shrink: 0;
}

.formula-eq {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.formula-frac {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
  position: relative;
  padding: 0 6px;
}

.frac-num {
  padding-bottom: 3px;
  border-bottom: 1.5px solid var(--text-dim);
  font-size: 0.8rem;
}

.frac-den {
  padding-top: 3px;
  font-size: 0.8rem;
}

.formula-highlight {
  color: var(--accent);
  font-weight: 700;
}

.formula-dim {
  color: var(--text-muted);
  font-size: 0.7rem;
  font-style: italic;
}

.formula-example {
  padding-top: 6px;
  border-top: 1px solid var(--border);
}

.formula-example strong {
  color: var(--accent);
}

/* ── Sticky Control Bar ───────────────────────────────────────────── */
.navbar {
  position: sticky;
  top: 2px;
  z-index: 100;
  background: rgba(8, 9, 13, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}

.controls-row {
  max-width: var(--content-max);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 10px var(--pad);
  flex-wrap: wrap;
}

.control-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

.control-label {
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  font-weight: 500;
}

.control-spacer { flex: 1; min-width: 8px; }

.playback-group {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
  min-width: 240px;
  border-left: 1px solid var(--border);
  padding-left: 20px;
  margin-left: 6px;
}

.timeline-range { flex: 1; min-width: 80px; }

/* Toggle buttons */
.toggle-group { display: flex; }

.toggle-btn {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 5px 14px;
  font-size: 0.75rem;
  cursor: pointer;
  transition: all 0.15s;
  font-family: inherit;
}
.toggle-btn:first-child { border-radius: var(--radius-sm) 0 0 var(--radius-sm); }
.toggle-btn:last-child  { border-radius: 0 var(--radius-sm) var(--radius-sm) 0; }
.toggle-btn:not(:first-child) { border-left: none; }

.toggle-btn.active {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
  font-weight: 600;
}
.toggle-btn:hover:not(.active) { background: var(--bg-elevated); color: var(--text); }

select {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 5px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-family: inherit;
  cursor: pointer;
}
select:focus { outline: none; border-color: var(--accent); }

.mode-select {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 5px 28px 5px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-family: inherit;
  cursor: pointer;
  appearance: none;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M0 0l5 6 5-6z' fill='%234a4f62'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 8px center;
  min-width: 200px;
  max-width: 320px;
}
.mode-select:focus { outline: none; border-color: var(--accent); }
.mode-select option[disabled] { color: var(--text-muted); font-style: italic; }
.mode-select optgroup { color: var(--text-dim); font-size: 0.68rem; }

.play-btn {
  background: var(--accent);
  border: none;
  color: var(--bg);
  padding: 6px 18px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  font-family: inherit;
  white-space: nowrap;
}
.play-btn:hover { opacity: 0.85; }
.play-btn.playing { background: var(--accent2); }

input[type="range"] { accent-color: var(--accent); }
.speed-range { width: 56px; }

.slider-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-dim);
  min-width: 42px;
  white-space: nowrap;
}

/* ── Metrics Cards ────────────────────────────────────────────────── */
#metrics-bar {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 14px var(--pad) 20px;
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 12px;
}

.metric-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 12px;
  text-align: center;
  transition: border-color 0.2s;
}

.metric-value {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent);
  display: block;
  line-height: 1.3;
}

.metric-label {
  font-size: 0.58rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-top: 6px;
  display: block;
}

.metric-card.highlight {
  border-color: var(--accent);
  background: var(--accent-dim);
}

/* ═══════════════════════════════════════════════════════════════════
   MAIN CONTENT — Two-column: Animations left, Info right
   ═══════════════════════════════════════════════════════════════════ */

#main-content {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--pad) 32px;
}

.content-grid {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 20px;
  align-items: start;
}

/* ── Left Column: Stacked Animations ──────────────────────────────── */
.anim-column {
  display: flex;
  flex-direction: column;
  gap: 10px;
  position: relative;
}

.viz-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.viz-panel-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 6px 14px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--bg-elevated) 0%, var(--bg-card) 100%);
}

.viz-panel-title {
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text);
  white-space: nowrap;
}

.viz-panel-body {
  display: flex;
  gap: 6px;
  padding: 6px;
}

.viz-canvas-wrap {
  flex: 1;
  line-height: 0;
  min-width: 0;
}

.viz-canvas {
  display: block;
  width: 100%;
  aspect-ratio: 2 / 1;
  cursor: crosshair;
  border-radius: 4px;
  image-rendering: auto;
}

.viz-cbar {
  width: 28px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: 2px 0;
  flex-shrink: 0;
}

.viz-cbar canvas {
  width: 10px;
  flex: 1;
  border-radius: 2px;
  border: 1px solid var(--border);
}

.cbar-tick {
  font-family: var(--font-mono);
  font-size: 0.5rem;
  color: var(--text-muted);
  white-space: nowrap;
}

/* ── Pin Status ──────────────────────────────────────────────────── */
.pin-status {
  font-size: 0.72rem;
  color: var(--text-dim);
  padding: 6px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-align: center;
}
.pin-status a {
  color: var(--accent);
  text-decoration: none;
}
.pin-status a:hover {
  text-decoration: underline;
}

/* ── Right Column: Info (sticky sidebar) ──────────────────────────── */
.info-column {
  position: sticky;
  top: 60px;      /* just below sticky navbar */
  align-self: start;
  display: flex;
  flex-direction: column;
  gap: 12px;
  max-height: calc(100vh - 80px);
  overflow-y: auto;
  /* Hide scrollbar but keep scrollable */
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}

.info-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
}

.info-panel h3 {
  font-size: 0.78rem;
  font-weight: 600;
  margin-bottom: 10px;
}

.dim-text {
  font-weight: 400;
  color: var(--text-dim);
  font-size: 0.68rem;
}

/* ── Bit Inspector (live hover) ───────────────────────────────────── */
.bit-inspector {
  border-color: var(--accent);
  border-width: 1px;
  background: linear-gradient(135deg, var(--bg-card), rgba(79, 195, 247, 0.03));
}

.bit-placeholder {
  font-size: 0.72rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 6px;
  font-style: italic;
}

.bit-section {
  margin-bottom: 8px;
}

.bit-section-label {
  display: block;
  font-size: 0.6rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.bit-legend {
  display: flex;
  gap: 14px;
  font-size: 0.65rem;
  color: var(--text-dim);
  margin-top: 6px;
  padding-top: 8px;
  border-top: 1px solid var(--border);
}

.bit-legend span {
  display: flex;
  align-items: center;
  gap: 4px;
}

.bit-swatch {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 2px;
}
.bit-swatch.sign { background: var(--bit-sign); }
.bit-swatch.exp  { background: var(--bit-exp); }
.bit-swatch.mant { background: var(--bit-mant); }

/* ── Bit rows (shared by inspector + reference panels) ────────────── */
.bit-row {
  display: flex;
  align-items: center;
  gap: 5px;
  margin-bottom: 5px;
}

.bit-row-label {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  color: var(--text-dim);
  min-width: 18px;
  text-align: right;
  flex-shrink: 0;
}

.bit-row-value {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  color: var(--accent);
  min-width: 50px;
  flex-shrink: 0;
}

.bit-boxes { display: flex; gap: 1px; flex-shrink: 1; min-width: 0; }

.bit-box {
  width: 3px;
  height: 10px;
  border-radius: 1px;
  flex-shrink: 0;
}
/* Bit = 1: bright color */
.bit-box.sign { background: var(--bit-sign); }
.bit-box.exp  { background: var(--bit-exp); }
.bit-box.mant { background: var(--bit-mant); }

/* Bit = 0: dim color */
.bit-box.bit-off.sign { background: rgba(239, 83, 80, 0.15); }
.bit-box.bit-off.exp  { background: rgba(66, 165, 245, 0.15); }
.bit-box.bit-off.mant { background: rgba(102, 187, 106, 0.15); }

/* ── Coordinate System ────────────────────────────────────────────── */
.coord-panel h3 {
  margin-bottom: 12px;
}

#coord-canvas {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-sm);
  background: #080810;
  margin-bottom: 10px;
}

.coord-controls {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.coord-color-label { margin-left: 6px; }

/* ── Coming Soon Overlay ─────────────────────────────────────────── */
.coming-soon-overlay {
  position: absolute;
  inset: 0;
  background: rgba(8, 9, 13, 0.88);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius);
  z-index: 10;
}

.coming-soon-inner {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}

.coming-soon-icon { font-size: 2.5rem; }

.coming-soon-inner p {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
}

.coming-soon-sub {
  font-size: 0.82rem;
  color: var(--text-dim);
}

/* ── Footer ───────────────────────────────────────────────────────── */
footer {
  text-align: center;
  padding: 32px var(--pad);
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.78rem;
}

/* ── Responsive ───────────────────────────────────────────────────── */
@media (max-width: 1100px) {
  .content-grid {
    grid-template-columns: 1fr;
  }

  .info-column {
    position: static;
    max-height: none;
    overflow-y: visible;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }

  .info-panel.bit-inspector {
    grid-column: 1 / -1;
  }

  .coord-panel {
    grid-column: 1 / -1;
  }
}

@media (max-width: 768px) {
  :root { --pad: 16px; }

  #page-header {
    flex-direction: column;
    padding-top: 32px;
    gap: 12px;
  }

  #metrics-bar {
    grid-template-columns: repeat(3, 1fr);
  }

  .info-column {
    grid-template-columns: 1fr;
  }

  .info-panel.bit-inspector {
    grid-column: 1;
  }

  .coord-panel {
    grid-column: 1;
  }

  .playback-group {
    width: 100%;
    min-width: unset;
  }
}

@media (max-width: 480px) {
  #metrics-bar {
    grid-template-columns: repeat(2, 1fr);
  }

  .controls-row {
    gap: 10px;
  }
}