:root {
  color-scheme: light;
  --surface-0: #f6f5f1;
  --surface-1: #fcfcfb;
  --surface-2: #efeee9;
  --border: #dddcd5;
  --text-primary: #0b0b0b;
  --text-secondary: #52514e;
  --text-muted: #77766f;
  --accent: #1c7a3c;
  --series-1: #2a78d6;   /* forwards  */
  --series-2: #eb6834;   /* backwards */
  --series-3: #1baf7a;
  --grid: #e6e5df;
  --frog: #6fbf4a;
  --code-bg: #efeee9;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --surface-0: #121211;
    --surface-1: #1a1a19;
    --surface-2: #242422;
    --border: #3a3a37;
    --text-primary: #f0efec;
    --text-secondary: #c3c2b7;
    --text-muted: #96958c;
    --accent: #5cc27f;
    --series-1: #3987e5;
    --series-2: #d95926;
    --series-3: #199e70;
    --grid: #2c2c2a;
    --frog: #7ccf55;
    --code-bg: #242422;
  }
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --surface-0: #121211;
  --surface-1: #1a1a19;
  --surface-2: #242422;
  --border: #3a3a37;
  --text-primary: #f0efec;
  --text-secondary: #c3c2b7;
  --text-muted: #96958c;
  --accent: #5cc27f;
  --series-1: #3987e5;
  --series-2: #d95926;
  --series-3: #199e70;
  --grid: #2c2c2a;
  --frog: #7ccf55;
  --code-bg: #242422;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--surface-0);
  color: var(--text-primary);
  font: 17px/1.6 "Source Serif 4", Georgia, serif;
}
h1, h2, h3, .ui, .tile, figcaption, table, .chart, nav { font-family: "Inter", system-ui, -apple-system, sans-serif; }
h1 { font-size: clamp(2rem, 5vw, 3.2rem); line-height: 1.1; margin: 0 0 .4em; letter-spacing: -0.02em; }
h2 { font-size: 1.6rem; margin: 2.4em 0 .6em; letter-spacing: -0.01em; }
h3 { font-size: 1.15rem; margin: 1.8em 0 .4em; }
p { margin: 0 0 1em; }
a { color: var(--accent); }
code { background: var(--code-bg); padding: 0.1em 0.35em; border-radius: 4px; font-size: 0.88em; }
pre { background: var(--code-bg); padding: 14px 16px; border-radius: 8px; overflow-x: auto; font-size: 0.85em; line-height: 1.45; }
pre code { background: none; padding: 0; }

.wrap { max-width: 860px; margin: 0 auto; padding: 0 16px; }
.wide { max-width: 1180px; margin: 0 auto; padding: 0 16px; }

header.hero { padding: 48px 0 8px; }
.kicker { font-family: Inter, system-ui, sans-serif; text-transform: uppercase; letter-spacing: .12em; font-size: .78rem; color: var(--accent); font-weight: 600; margin-bottom: 10px; }
.lede { font-size: 1.2rem; color: var(--text-secondary); max-width: 46em; }

.viewer {
  position: relative; height: min(68vh, 620px); min-height: 380px;
  background: radial-gradient(ellipse at 50% 40%, var(--surface-1), var(--surface-2));
  border: 1px solid var(--border); border-radius: 14px; overflow: hidden; margin: 18px 0 8px;
}
.viewer canvas { display: block; width: 100%; height: 100%; touch-action: none; }
.viewer .controls {
  position: absolute; left: 12px; top: 12px; right: 12px; display: flex; gap: 8px; flex-wrap: wrap; pointer-events: none;
}
.seg { display: inline-flex; background: var(--surface-1); border: 1px solid var(--border); border-radius: 999px; padding: 3px; pointer-events: auto; box-shadow: 0 1px 3px rgba(0,0,0,.08); }
.seg button {
  font: 600 13px Inter, system-ui, sans-serif; border: 0; background: transparent; color: var(--text-secondary);
  padding: 6px 12px; border-radius: 999px; cursor: pointer; min-height: 32px;
}
.seg button[aria-pressed="true"] { background: var(--text-primary); color: var(--surface-1); }
.viewer .legend {
  position: absolute; left: 12px; bottom: 12px; background: var(--surface-1); border: 1px solid var(--border);
  border-radius: 10px; padding: 8px 10px; font: 12px/1.3 Inter, system-ui, sans-serif; color: var(--text-secondary);
}
.viewer .legend .bar { width: 180px; height: 10px; border-radius: 3px; margin: 4px 0 2px; }
.viewer .legend .ends { display: flex; justify-content: space-between; }
.viewer .hint { position: absolute; right: 12px; bottom: 12px; font: 12px Inter, system-ui, sans-serif; color: var(--text-muted); }
.viewer .readout {
  position: absolute; right: 12px; bottom: 36px; background: var(--surface-1); border: 1px solid var(--border); border-radius: 10px;
  padding: 8px 12px; font: 13px/1.4 Inter, system-ui, sans-serif; color: var(--text-secondary); pointer-events: none;
}
.viewer .readout b { color: var(--text-primary); font-size: 1.3em; }

.tiles { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin: 24px 0; }
.tile { background: var(--surface-1); border: 1px solid var(--border); border-radius: 12px; padding: 14px 16px; }
.tile .label { font-size: .8rem; color: var(--text-secondary); display: flex; align-items: center; gap: 6px; }
.tile .value { font-size: 2rem; font-weight: 650; letter-spacing: -0.02em; font-variant-numeric: tabular-nums; }
.tile .sub { font-size: .8rem; color: var(--text-muted); }
.swatch { width: 10px; height: 10px; border-radius: 3px; display: inline-block; flex: none; }

.verdict { background: var(--surface-1); border: 1px solid var(--border); border-left: 4px solid var(--accent); border-radius: 10px; padding: 14px 18px; margin: 20px 0; }
.verdict p:last-child { margin: 0; }

figure { margin: 24px 0; }
figure img { width: 100%; height: auto; border-radius: 10px; border: 1px solid var(--border); background: #fff; display: block; }
figcaption { font-size: .85rem; color: var(--text-secondary); margin-top: 8px; line-height: 1.45; }
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
@media (max-width: 720px) { .grid2 { grid-template-columns: 1fr; } }

.chart { background: var(--surface-1); border: 1px solid var(--border); border-radius: 12px; padding: 14px 14px 8px; margin: 18px 0; position: relative; }
.chart .title { font-weight: 600; font-size: .95rem; }
.chart .subtitle { font-size: .8rem; color: var(--text-secondary); margin-bottom: 6px; }
.chart svg { display: block; width: 100%; height: auto; overflow: visible; }
.chart .axis text, .chart .lbl { fill: var(--text-secondary); font-size: 11px; }
.chart .axis line, .chart .axis path { stroke: var(--border); }
.chart .gridline { stroke: var(--grid); }
.chart .val { fill: var(--text-primary); font-size: 12px; font-weight: 600; }
.chart .legend-row { display: flex; gap: 14px; flex-wrap: wrap; font-size: .8rem; color: var(--text-secondary); margin: 2px 0 6px; }
.chart .legend-row span { display: inline-flex; align-items: center; gap: 6px; }
.tooltip {
  position: absolute; pointer-events: none; background: var(--surface-1); border: 1px solid var(--border); border-radius: 8px;
  padding: 6px 9px; font: 12px/1.4 Inter, system-ui, sans-serif; color: var(--text-primary); box-shadow: 0 4px 14px rgba(0,0,0,.12);
  opacity: 0; transition: opacity .1s; white-space: nowrap; z-index: 5;
}
.tooltip .muted { color: var(--text-secondary); }
details.table-view { font-size: .85rem; margin-top: 6px; }
details.table-view summary { cursor: pointer; color: var(--text-secondary); }

table { border-collapse: collapse; width: 100%; font-size: .88rem; margin: 12px 0 20px; font-variant-numeric: tabular-nums; }
th, td { text-align: left; padding: 7px 10px; border-bottom: 1px solid var(--border); }
th { color: var(--text-secondary); font-weight: 600; }
td.num, th.num { text-align: right; }
.table-scroll { overflow-x: auto; }

.race { background: var(--surface-1); border: 1px solid var(--border); border-radius: 12px; padding: 14px; margin: 18px 0; }
.race canvas { width: 100%; height: 420px; display: block; }
.race .ui-row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; font: 13px Inter, system-ui, sans-serif; color: var(--text-secondary); margin-bottom: 8px; }
.btn { font: 600 13px Inter, system-ui, sans-serif; border: 1px solid var(--border); background: var(--surface-2); color: var(--text-primary); padding: 7px 14px; border-radius: 8px; cursor: pointer; min-height: 34px; }

nav.toc { font-size: .85rem; display: flex; gap: 6px 16px; flex-wrap: wrap; padding: 10px 0; border-bottom: 1px solid var(--border); margin-bottom: 10px; }
nav.toc a { color: var(--text-secondary); text-decoration: none; }
nav.toc a:hover { color: var(--accent); }
.theme-toggle { margin-left: auto; }

footer { margin: 60px 0 40px; padding-top: 16px; border-top: 1px solid var(--border); font: 13px Inter, system-ui, sans-serif; color: var(--text-muted); }
.note { font-size: .9rem; color: var(--text-secondary); }
ul { padding-left: 1.2em; }
li { margin: .25em 0; }
@media (max-width: 720px) { .tiles { grid-template-columns: repeat(2, minmax(0, 1fr)); } .tile .value { font-size: 1.6rem; } }
@media (max-width: 600px) { .viewer .hint { display: none; } }