/* Unsung project site. Same palette as the explorer (DESIGN §10.9); system fonts, no remote assets. */
:root {
  --bg: #0d1016;
  --surface: #151a22;
  --surface-2: #1c2330;
  --line: #263041;
  --text: #e6e9ef;
  --soft: #c5ccd7;
  --muted: #8b93a3;
  --quality: #7ee0a3;
  --confidence: #7fb4ff;
  --attention: #9a8f7a;
  --quarantine: #ffb454;
  --radius: 14px;
  --max: 1120px;
  --gutter: max(20px, calc((100vw - var(--max)) / 2));
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "Cascadia Code", Menlo, Consolas, monospace;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 var(--sans);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--confidence); text-underline-offset: 3px; }
a:hover { color: #a9ccff; }
:focus-visible { outline: 2px solid var(--confidence); outline-offset: 3px; border-radius: 6px; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 12px; z-index: 20; background: var(--surface-2); padding: 8px 12px; border-radius: 8px; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 14px var(--gutter);
  background: rgba(13, 16, 22, 0.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--text); text-decoration: none; font-weight: 700; }
.brand:hover { color: var(--text); }
.logo {
  display: inline-grid; place-items: center; width: 28px; height: 28px;
  border-radius: 8px; background: var(--quality); color: var(--bg); font-weight: 800;
}
.site-header nav { display: flex; align-items: center; gap: 20px; }
.site-header nav a { color: var(--muted); text-decoration: none; font-size: 15px; }
.site-header nav a:hover { color: var(--text); }
.site-header nav a.gh { color: var(--text); border: 1px solid var(--line); padding: 4px 14px; border-radius: 999px; }
.site-header nav a.gh:hover { border-color: #3a475d; }

/* Sections */
main > section { padding: 76px var(--gutter); }
.band { background: linear-gradient(180deg, var(--surface) 0%, #10141b 100%); border-block: 1px solid var(--line); }
h1, h2, h3 { text-wrap: balance; }
h2 { font-size: clamp(26px, 3.4vw, 36px); line-height: 1.15; letter-spacing: -0.01em; margin: 0 0 12px; }
h3 { font-size: 18px; margin: 0 0 8px; }
p { text-wrap: pretty; }
.sub { color: var(--muted); margin: 0 0 30px; max-width: 64ch; }

/* Hero */
.hero {
  text-align: center;
  padding-top: 92px;
  background: radial-gradient(1000px 440px at 50% -80px, rgba(126, 224, 163, 0.15), transparent 70%);
}
.eyebrow { color: var(--quality); font: 600 13px/1 var(--mono); letter-spacing: 0.08em; text-transform: uppercase; margin: 0 0 20px; }
h1 { font-size: clamp(38px, 6.4vw, 68px); line-height: 1.04; letter-spacing: -0.025em; margin: 0 auto 22px; max-width: 15ch; }
.accent { color: var(--quality); }
.lede { color: var(--soft); font-size: clamp(17px, 2.1vw, 20px); max-width: 62ch; margin: 0 auto 32px; }
.cta { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; margin-bottom: 52px; }
.button {
  display: inline-block; padding: 11px 20px; border-radius: 10px;
  border: 1px solid var(--line); background: var(--surface-2);
  color: var(--text); text-decoration: none; font-weight: 600;
}
.button:hover { border-color: #3a475d; color: var(--text); }
.button.primary { background: var(--quality); border-color: var(--quality); color: #0b1a12; }
.button.primary:hover { background: #9aeabb; color: #0b1a12; }

.shot { margin: 0 auto; max-width: 1080px; }
.shot img {
  display: block; width: 100%; height: auto;
  border-radius: 12px; border: 1px solid var(--line);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.55);
}
.shot figcaption { color: var(--muted); font-size: 14px; margin-top: 14px; }
.shot.small { max-width: none; margin: 0; }

/* The problem */
.problem { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 44px; }
.problem p { color: var(--soft); margin: 0; }

/* How it decides */
.meters { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.meter { background: var(--surface); border: 1px solid var(--line); border-top: 3px solid; border-radius: var(--radius); padding: 22px; }
.meter p { color: var(--soft); margin: 0; font-size: 15px; }
.meter.quality { border-top-color: var(--quality); }
.meter.quality h3 { color: var(--quality); }
.meter.confidence { border-top-color: var(--confidence); }
.meter.confidence h3 { color: var(--confidence); }
.meter.attention { border-top-color: var(--attention); }
.meter.attention h3 { color: var(--attention); }
.formula { text-align: center; margin: 30px 0 24px; }
.formula code {
  display: inline-block; background: var(--surface-2); border: 1px solid var(--line);
  padding: 9px 16px; border-radius: 8px; font: 15px/1.4 var(--mono); color: var(--text);
}
.lanes { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px 28px; color: var(--soft); }
.lanes strong { color: var(--text); display: inline-block; min-width: 8.5em; }

/* Evidence */
.stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; margin-bottom: 38px; }
.stat { background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; }
.stat .big { display: block; font: 700 46px/1 var(--sans); color: var(--quality); letter-spacing: -0.02em; margin-bottom: 10px; }
.stat .big small { font-size: 22px; font-weight: 600; color: var(--muted); }
.stat span:last-child { color: var(--soft); font-size: 15px; }
.stat:last-child .big { color: var(--quarantine); }
.bars { display: grid; gap: 12px; max-width: 780px; }
.bar { display: grid; grid-template-columns: 11em minmax(0, 1fr) 3.5em; gap: 14px; align-items: center; color: var(--soft); font-size: 15px; }
.track { height: 12px; background: var(--bg); border: 1px solid var(--line); border-radius: 999px; overflow: hidden; }
.track > span { display: block; height: 100%; border-radius: 999px; background: linear-gradient(90deg, #5cc488, var(--quality)); }
.bar.low .track > span { background: var(--attention); }
.bar > span:last-child { text-align: right; color: var(--text); font-variant-numeric: tabular-nums; }
.note { color: var(--muted); font-size: 15px; margin: 26px 0 0; max-width: 74ch; }

/* Explanations */
.split { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: 44px; align-items: center; }
.split p { color: var(--soft); }
kbd {
  font: 14px/1.4 var(--mono); background: var(--surface-2); color: var(--text);
  border: 1px solid var(--line); border-bottom-width: 2px; border-radius: 6px; padding: 1px 7px;
}

/* Get started */
.start pre {
  margin: 0 0 20px; padding: 18px 22px; overflow-x: auto;
  background: var(--bg); border: 1px solid var(--line); border-radius: 12px;
  font: 15px/1.75 var(--mono); color: #d5dbe5;
}
.start p { color: var(--soft); max-width: 74ch; }

/* Principles */
.principles ul { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px 36px; }
.principles li { position: relative; padding-left: 22px; color: var(--soft); }
.principles li::before {
  content: ""; position: absolute; left: 0; top: 0.62em;
  width: 8px; height: 8px; border-radius: 50%; background: var(--quality);
}
.principles strong { color: var(--text); }

/* Footer */
.site-footer { border-top: 1px solid var(--line); padding: 34px 20px 52px; text-align: center; color: var(--muted); font-size: 14px; }
.site-footer p { margin: 6px 0; }
.muted { color: var(--muted); }

@media (max-width: 880px) {
  .problem, .split, .lanes, .principles ul, .meters { grid-template-columns: minmax(0, 1fr); }
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .site-header nav a:not(.gh) { display: none; }
}
@media (max-width: 480px) {
  main > section { padding-block: 54px; }
  .bar { grid-template-columns: 7.5em minmax(0, 1fr) 3em; font-size: 14px; }
  .stat .big { font-size: 36px; }
  .lanes strong { display: block; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}