:root {
  --bg: #05070b;
  --surface: #0b0e14;
  --card: #0d1118;
  --card-edge: rgba(255, 255, 255, 0.06);
  --ink: #e8ecf3;
  --ink-2: #9aa5b5;
  --ink-3: #5c6675;
  --mono: ui-monospace, "SF Mono", "Cascadia Code", "JetBrains Mono", Menlo, Consolas, monospace;
  --green: #4ade80;
  --purple: #a78bfa;
  --blue: #38bdf8;
  --indigo: #818cf8;
  --teal: #2dd4bf;
  --emerald: #34d399;
  --magenta: #f472b6;
  --pink: #ec4899;
  --orange: #fbbf24;
  --red: #f87171;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Inter, sans-serif;
  line-height: 1.5;
  overflow-x: hidden;
}

.bg-glow {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(600px 400px at 15% -5%, rgba(74, 222, 128, 0.07), transparent 70%),
    radial-gradient(700px 500px at 90% 20%, rgba(56, 189, 248, 0.05), transparent 70%),
    radial-gradient(600px 500px at 50% 110%, rgba(236, 72, 153, 0.06), transparent 70%);
  z-index: 0;
}

main, header, footer { position: relative; z-index: 1; }

/* ── Hero ─────────────────────────────────────────── */

.hero {
  max-width: 900px;
  margin: 0 auto;
  padding: 56px 20px 28px;
  text-align: center;
}

.hero h1 {
  font-size: clamp(1.5rem, 4.5vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35em;
  justify-content: center;
  align-items: center;
}

.hero-pill {
  background: linear-gradient(100deg, #22c55e, #4ade80);
  color: #04120a;
  padding: 0.08em 0.45em;
  border-radius: 0.25em;
  box-shadow: 0 0 30px rgba(74, 222, 128, 0.35);
}

.hero-sub {
  margin-top: 14px;
  color: var(--ink-2);
  font-size: 1rem;
}

/* ── Patterns table ───────────────────────────────── */

.patterns {
  max-width: 900px;
  margin: 0 auto;
  padding: 12px 16px 40px;
}

.table-head {
  display: grid;
  grid-template-columns: minmax(200px, 1fr) minmax(220px, 1.15fr) 150px;
  gap: 16px;
  padding: 8px 18px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-3);
}

.th-right { text-align: right; }

.row {
  display: grid;
  grid-template-columns: minmax(200px, 1fr) minmax(220px, 1.15fr) 150px;
  gap: 16px;
  align-items: center;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.02), rgba(255, 255, 255, 0.005)), var(--card);
  border: 1px solid var(--card-edge);
  border-radius: 14px;
  padding: 18px;
  margin-bottom: 12px;
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.row.seen { opacity: 1; transform: none; }

.p-name {
  font-weight: 700;
  font-size: 0.98rem;
  color: var(--c);
  margin-bottom: 8px;
}

.p-code {
  font-family: var(--mono);
  font-size: 0.78rem;
  line-height: 1.65;
  color: var(--ink-2);
  white-space: pre;
  overflow-x: auto;
}

.p-code .kw { color: var(--ink); }
.p-code .num { color: var(--orange); }
.p-code .fn { color: var(--blue); }

.viz {
  min-height: 74px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  position: relative;
}

.viz-caption {
  font-family: var(--mono);
  font-size: 0.66rem;
  color: var(--ink-3);
  text-align: right;
}

.bigo { text-align: right; }

.bigo-label {
  font-family: var(--mono);
  font-weight: 800;
  font-size: 1.35rem;
  color: var(--c);
  text-shadow: 0 0 18px color-mix(in srgb, var(--c) 45%, transparent);
  white-space: nowrap;
}

.bigo-sub {
  font-size: 0.7rem;
  color: var(--ink-2);
  margin-top: 4px;
}

/* cells */
.cells { display: flex; gap: 4px; flex-wrap: nowrap; }

.cell {
  width: 15px;
  height: 15px;
  flex: 0 0 auto;
  border-radius: 4px;
  border: 1.5px solid rgba(255, 255, 255, 0.13);
  background: transparent;
  transition: background 0.18s, border-color 0.18s, box-shadow 0.18s;
}

.cell.on {
  background: var(--c);
  border-color: var(--c);
  box-shadow: 0 0 8px color-mix(in srgb, var(--c) 60%, transparent);
}

.cell.hot {
  background: #fff;
  border-color: #fff;
  box-shadow: 0 0 10px rgba(255, 255, 255, 0.7);
}

.cell.dim { opacity: 0.35; }

/* hash lookup */
.hash-wrap { position: relative; padding-top: 22px; }

.key-chip {
  position: absolute;
  top: 0;
  left: 0;
  font-family: var(--mono);
  font-size: 0.62rem;
  color: var(--c);
  border: 1px solid var(--c);
  border-radius: 6px;
  padding: 0 5px;
  background: color-mix(in srgb, var(--c) 12%, transparent);
  transition: left 0.45s cubic-bezier(0.5, 0, 0.2, 1.3);
}

/* halving bar */
.bar-track {
  position: relative;
  height: 18px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  overflow: hidden;
}

.bar-fill {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  border-radius: 5px;
  background: color-mix(in srgb, var(--c) 45%, transparent);
  border: 1.5px solid var(--c);
  box-shadow: 0 0 10px color-mix(in srgb, var(--c) 40%, transparent);
  transition: width 0.45s ease, left 0.45s ease;
}

.bar-label {
  font-family: var(--mono);
  font-size: 0.66rem;
  color: var(--c);
  text-align: center;
  min-height: 1em;
}

/* pointer for single loop */
.pointer-lane { position: relative; height: 12px; }

.pointer {
  position: absolute;
  top: 0;
  font-size: 0.6rem;
  color: var(--c);
  transition: left 0.14s linear;
}

.lane-tag {
  font-family: var(--mono);
  font-size: 0.62rem;
  color: var(--ink-3);
  width: 12px;
  flex: 0 0 auto;
  align-self: center;
}

.dual-lane { display: flex; gap: 6px; align-items: center; }

/* divide & conquer levels */
.dnc { display: flex; flex-direction: column; gap: 5px; }

.dnc-level { display: flex; gap: 5px; opacity: 0; transition: opacity 0.4s ease; }

.dnc-level.show { opacity: 1; }

.dnc-bar {
  height: 12px;
  flex: 1;
  border-radius: 6px;
  border: 1.5px solid var(--c);
  background: color-mix(in srgb, var(--c) 14%, transparent);
  box-shadow: 0 0 8px color-mix(in srgb, var(--c) 25%, transparent);
}

/* grids */
.grid7 { display: grid; grid-template-columns: repeat(7, 13px); gap: 3px; justify-content: end; }

.grid7 .cell { width: 13px; height: 13px; border-radius: 3.5px; }

.tri-rows { display: flex; flex-direction: column; gap: 3px; align-items: flex-start; }

.tri-rows .cells { gap: 3px; }

.tri-rows .cell { width: 13px; height: 13px; border-radius: 3.5px; }

.viz-flex { display: flex; gap: 12px; align-items: center; justify-content: flex-end; }

.viz-note {
  font-family: var(--mono);
  font-size: 0.64rem;
  color: var(--ink-3);
  white-space: pre-line;
}

/* svg trees */
.tree-svg { width: 100%; height: 92px; overflow: visible; }

.tree-svg .node {
  fill: color-mix(in srgb, var(--c) 20%, #0d1118);
  stroke: var(--c);
  stroke-width: 1.5;
  opacity: 0;
  transition: opacity 0.35s ease;
}

.tree-svg .edge {
  stroke: color-mix(in srgb, var(--c) 55%, transparent);
  stroke-width: 1.2;
  opacity: 0;
  transition: opacity 0.35s ease;
}

.tree-svg .tlabel {
  font-family: var(--mono);
  font-size: 9px;
  fill: var(--c);
  opacity: 0;
  transition: opacity 0.35s ease;
}

.tree-svg .show { opacity: 1; }

/* ── Chart section ────────────────────────────────── */

.chart-section {
  max-width: 900px;
  margin: 0 auto;
  padding: 30px 16px 60px;
}

.chart-section h2 {
  font-size: clamp(1.3rem, 3.5vw, 1.9rem);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.chart-section .accent {
  background: linear-gradient(100deg, #38bdf8, #a78bfa);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.chart-sub { color: var(--ink-2); margin: 8px 0 18px; font-size: 0.92rem; }

.chart-sub code { font-family: var(--mono); color: var(--ink); }

.chart-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
}

.legend { display: flex; flex-wrap: wrap; gap: 8px; }

.chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink);
  background: var(--card);
  border: 1px solid var(--card-edge);
  border-radius: 999px;
  padding: 5px 12px;
  cursor: pointer;
  transition: opacity 0.2s, border-color 0.2s;
}

.chip .dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--c);
  box-shadow: 0 0 6px color-mix(in srgb, var(--c) 70%, transparent);
}

.chip[aria-pressed="false"] { opacity: 0.38; }

.chip:hover { border-color: color-mix(in srgb, var(--c) 60%, transparent); }

.ctrl-right { display: flex; gap: 10px; align-items: center; }

.seg {
  display: inline-flex;
  border: 1px solid var(--card-edge);
  border-radius: 9px;
  overflow: hidden;
  background: var(--card);
}

.seg-btn {
  font-family: var(--mono);
  font-size: 0.76rem;
  color: var(--ink-2);
  background: transparent;
  border: none;
  padding: 6px 14px;
  cursor: pointer;
}

.seg-btn.active { background: rgba(255, 255, 255, 0.08); color: var(--ink); }

.table-btn {
  border: 1px solid var(--card-edge);
  border-radius: 9px;
  background: var(--card);
}

.table-btn[aria-pressed="true"] { background: rgba(255, 255, 255, 0.08); color: var(--ink); }

.chart-wrap {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--card-edge);
  border-radius: 16px;
  padding: 10px 6px 4px;
}

#chart { width: 100%; height: 420px; display: block; }

#chart text {
  font-family: var(--mono);
  font-size: 11px;
  fill: var(--ink-3);
}

#chart .grid-line { stroke: rgba(255, 255, 255, 0.05); }

#chart .axis-line { stroke: rgba(255, 255, 255, 0.14); }

#chart .series { fill: none; stroke-width: 2; }

#chart .direct-label { font-weight: 700; font-size: 12px; }

#chart .crosshair { stroke: rgba(255, 255, 255, 0.25); stroke-dasharray: 3 3; }

.tooltip {
  position: absolute;
  pointer-events: none;
  background: rgba(10, 13, 20, 0.95);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 10px;
  padding: 9px 12px;
  font-family: var(--mono);
  font-size: 0.74rem;
  min-width: 150px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.5);
  z-index: 5;
}

.tooltip .tt-n { color: var(--ink); font-weight: 700; margin-bottom: 5px; }

.tooltip .tt-row {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  color: var(--ink-2);
  line-height: 1.7;
}

.tooltip .tt-row b { color: var(--ink); font-weight: 600; }

.tooltip .tt-key { display: inline-flex; align-items: center; gap: 6px; }

.tooltip .dot { width: 7px; height: 7px; border-radius: 50%; flex: 0 0 auto; }

.table-wrap {
  margin-top: 14px;
  overflow-x: auto;
  border: 1px solid var(--card-edge);
  border-radius: 14px;
  background: var(--surface);
}

#values-table {
  border-collapse: collapse;
  width: 100%;
  font-family: var(--mono);
  font-size: 0.76rem;
}

#values-table caption {
  text-align: left;
  padding: 12px 14px 4px;
  color: var(--ink-2);
  font-family: inherit;
}

#values-table th, #values-table td {
  padding: 7px 14px;
  text-align: right;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  color: var(--ink-2);
  white-space: nowrap;
}

#values-table th { color: var(--ink); position: sticky; top: 0; background: var(--surface); }

#values-table td:first-child, #values-table th:first-child { text-align: left; color: var(--ink); }

footer {
  text-align: center;
  color: var(--ink-3);
  font-size: 0.8rem;
  padding: 26px 16px 40px;
}

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

@media (max-width: 700px) {
  .table-head { display: none; }

  .row {
    grid-template-columns: 1fr auto;
    grid-template-areas: "name bigo" "viz viz";
    row-gap: 14px;
  }

  .row .pattern { grid-area: name; }
  .row .viz { grid-area: viz; }
  .row .bigo { grid-area: bigo; }

  .grid7, .viz-flex { justify-content: flex-start; }

  #chart { height: 340px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .row { opacity: 1; transform: none; transition: none; }
}