/* BayesBook — homepage styles
   Palette: near-black ground, bone text, single ochre accent.
   Type: monospace for the interface, a serif only for the headline voice. */

:root {
  --bg: #0c0c0b;
  --bg-raised: #121211;
  --line: #2a2a27;
  --line-soft: #1c1c1a;
  --ink: #e6e1d6;
  --ink-dim: #9a958a;
  --ink-faint: #5f5b53;
  --accent: #c9a24f;
  --accent-dim: #7a6433;
  --prior: #6f6a60;
  --post: #c9a24f;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --serif: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Palatino, Georgia, serif;
  --max: 1180px;
  --gutter: 24px;
}

* { box-sizing: border-box; }
html { background: var(--bg); }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--mono);
  font-size: 14px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: inherit; text-decoration: none; }
a:hover { color: var(--accent); }
::selection { background: var(--accent); color: var(--bg); }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 var(--gutter); }

/* ---- type helpers ---- */
.eyebrow {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-dim);
}
.eyebrow .num { color: var(--accent); margin-right: 10px; }
.serif { font-family: var(--serif); font-weight: 400; letter-spacing: -0.005em; }
.dim { color: var(--ink-dim); }
.faint { color: var(--ink-faint); }
.accent { color: var(--accent); }
p { margin: 0 0 1em; max-width: 62ch; }

/* ---- top bar ---- */
.topbar {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--line-soft);
}
.topbar .wrap {
  height: 52px;
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px;
}
.wordmark { display: flex; align-items: center; gap: 10px; font-size: 13px; letter-spacing: 0.18em; }
.wordmark .mark {
  width: 14px; height: 14px; border: 1px solid var(--ink); position: relative;
}
.wordmark .mark::after {
  content: ""; position: absolute; inset: 3px; background: var(--accent);
}
.nav { display: flex; gap: 28px; font-size: 12px; letter-spacing: 0.08em; text-transform: uppercase; }
.nav a { color: var(--ink-dim); }
.nav a:hover { color: var(--ink); }
.status { font-size: 11px; color: var(--ink-faint); letter-spacing: 0.06em; }
.status::before {
  content: ""; display: inline-block; width: 6px; height: 6px; border-radius: 50%;
  background: var(--accent); margin-right: 8px; vertical-align: 1px;
}

/* auth controls (right of the top bar; revealed by auth.js) */
.topbar-right { display: flex; align-items: center; gap: 24px; }
.auth, .auth-out, .auth-in { display: flex; align-items: center; }
.auth[hidden], .auth-out[hidden], .auth-in[hidden] { display: none; }
.auth-out { gap: 18px; }
.auth-link {
  background: none; border: 0; padding: 0; cursor: pointer;
  font: inherit; font-size: 12px; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-dim);
}
.auth-link:hover { color: var(--ink); }
.auth .btn.small {
  padding: 7px 12px; font-size: 11px; cursor: pointer;
  background: transparent; color: var(--ink); font-family: inherit; line-height: inherit;
}
.auth .btn.small:hover { background: var(--ink); color: var(--bg); }
.auth-in { min-height: 28px; }

/* ---- sections ---- */
section { padding: 96px 0; border-bottom: 1px solid var(--line-soft); }
.section-head {
  display: grid; grid-template-columns: 1fr 2fr; gap: 40px;
  margin-bottom: 56px;
}
.section-head h2 {
  margin: 0; font-size: 30px; line-height: 1.15;
}
.section-head .lede { font-size: 15px; color: var(--ink-dim); margin: 0; }

/* ---- hero ---- */
.hero { padding: 112px 0 96px; }
.hero .grid {
  display: grid; grid-template-columns: 7fr 5fr; gap: 56px; align-items: start;
}
.hero h1 {
  margin: 22px 0 28px;
  font-size: clamp(38px, 5.2vw, 64px);
  line-height: 1.04;
}
.hero h1 em { font-style: italic; color: var(--accent); }
.hero .lede { font-size: 16px; color: var(--ink-dim); max-width: 56ch; }
.cta-row { display: flex; gap: 14px; margin-top: 36px; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 12px 18px;
  border: 1px solid var(--ink); font-size: 12px; letter-spacing: 0.1em; text-transform: uppercase;
}
.btn:hover { background: var(--ink); color: var(--bg); }
.btn.ghost { border-color: var(--line); color: var(--ink-dim); }
.btn.ghost:hover { border-color: var(--ink); color: var(--ink); background: transparent; }

/* console panel */
.console {
  border: 1px solid var(--line); background: var(--bg-raised);
  font-size: 12.5px; line-height: 1.55;
}
.console .bar {
  display: flex; justify-content: space-between; align-items: center;
  padding: 10px 14px; border-bottom: 1px solid var(--line);
  font-size: 11px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-dim);
}
.console .body { padding: 16px 14px 18px; }
.console .row { display: grid; grid-template-columns: 92px 1fr; gap: 12px; padding: 4px 0; }
.console .k { color: var(--ink-faint); }
.console .v { color: var(--ink); }
.console hr { border: 0; border-top: 1px dashed var(--line); margin: 14px 0; }
.console table { width: 100%; border-collapse: collapse; }
.console th, .console td { text-align: left; padding: 5px 0; font-weight: 400; }
.console th { color: var(--ink-faint); font-size: 11px; letter-spacing: 0.08em; text-transform: uppercase; border-bottom: 1px solid var(--line); }
.console td.n { text-align: right; font-variant-numeric: tabular-nums; }
.console td.w { color: var(--accent); }
.console .foot { margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--line); color: var(--ink-dim); }
.console .foot b { color: var(--ink); font-weight: 400; }
.blink { display: inline-block; width: 7px; height: 13px; background: var(--accent); vertical-align: -2px; animation: blink 1.1s steps(1) infinite; }
@keyframes blink { 50% { opacity: 0; } }

/* ---- pipeline strip ---- */
.strip { border-bottom: 1px solid var(--line-soft); }
.strip .wrap {
  display: grid; grid-template-columns: repeat(4, 1fr);
  padding-top: 0; padding-bottom: 0;
}
.strip .cell {
  padding: 18px 0; font-size: 11px; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--ink-dim); display: flex; gap: 12px; align-items: baseline;
  border-left: 1px solid var(--line-soft); padding-left: 16px;
}
.strip .cell:first-child { border-left: 0; padding-left: 0; }
.strip .cell .sym { font-family: var(--serif); font-style: italic; font-size: 15px; color: var(--ink); text-transform: none; letter-spacing: 0; }

/* ---- math ---- */
.math-grid { display: grid; grid-template-columns: 5fr 7fr; gap: 56px; align-items: start; }
.formula {
  border: 1px solid var(--line); background: var(--bg-raised); padding: 28px 28px 24px;
  font-family: var(--serif); font-size: 30px; line-height: 1.1; color: var(--ink);
}
.formula .frac { display: inline-grid; grid-template-rows: auto auto; text-align: center; vertical-align: middle; margin: 0 6px; }
.formula .frac > span:first-child { border-bottom: 1px solid var(--ink); padding: 0 8px 4px; }
.formula .frac > span:last-child { padding: 4px 8px 0; }
.formula .var { font-style: italic; }
.formula .lbl { font-family: var(--mono); font-size: 11px; letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-dim); margin-top: 22px; line-height: 1.8; }
.formula .lbl .accent { color: var(--accent); }
.formula sub, .formula sup { font-size: 0.5em; line-height: 0; }
.formula .sum { display: inline-grid; grid-template-rows: auto auto auto; justify-items: center; vertical-align: middle; margin: 0 4px; line-height: 1; }
.formula .sigma { font-size: 1.3em; line-height: 1; }
.formula .lim { font-size: 0.4em; font-style: italic; line-height: 1.2; }
.terms { margin-top: 28px; border-top: 1px solid var(--line); }
.terms dl { margin: 0; }
.terms .t { display: grid; grid-template-columns: 110px 1fr; gap: 16px; padding: 14px 0; border-bottom: 1px solid var(--line-soft); }
.terms dt { font-family: var(--serif); font-style: italic; font-size: 17px; color: var(--ink); }
.terms dt sub, .terms dt sup { font-size: 0.65em; line-height: 0; }
.terms dd { margin: 0; color: var(--ink-dim); font-size: 13px; }
.terms dd b { color: var(--ink); font-weight: 400; }

.figure { border: 1px solid var(--line); background: var(--bg-raised); }
.figure .cap {
  display: flex; justify-content: space-between; gap: 12px;
  padding: 10px 14px; border-bottom: 1px solid var(--line);
  font-size: 11px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-dim);
}
.figure svg { display: block; width: 100%; height: auto; }
.figure .legend { display: flex; flex-wrap: wrap; gap: 8px 22px; padding: 12px 14px; border-top: 1px solid var(--line); font-size: 11px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-dim); }
.figure .legend > span { white-space: nowrap; }
.legend .sw { display: inline-block; width: 18px; height: 0; border-top: 2px solid; vertical-align: 3px; margin-right: 8px; }
.legend .sw.prior { border-color: var(--prior); border-top-style: dashed; }
.legend .sw.post { border-color: var(--post); }

/* bar figure legend (Fig. 02) */
.legend .box { display: inline-block; width: 10px; height: 10px; vertical-align: -1px; margin-right: 8px; }
.legend .box.up { background: var(--accent); }
.legend .box.down { background: var(--prior); }
.legend .sw.mean { border-color: var(--ink-dim); border-top-style: dashed; }

/* ---- clusters (Fig. 03) legend swatches ---- */
.legend .dot { display: inline-block; width: 5px; height: 5px; border-radius: 50%; background: var(--ink-faint); margin: 0 10px 0 1px; vertical-align: 1px; }
.legend .ring { display: inline-block; width: 8px; height: 8px; border-radius: 50%; border: 1px solid var(--accent-dim); margin-right: 8px; vertical-align: 0; }
.legend .cross { color: var(--accent); margin-right: 8px; font-size: 12px; }
.legend .sw.path { border-color: var(--accent-dim); border-top-style: dashed; }

/* ---- principles ---- */
.principles { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0 56px; border-top: 1px solid var(--line); }
.principle { padding: 28px 0; border-bottom: 1px solid var(--line-soft); display: grid; grid-template-columns: 48px 1fr; gap: 16px; }
.principle .idx { font-size: 11px; color: var(--accent); letter-spacing: 0.1em; padding-top: 6px; }
.principle h3 { margin: 0 0 10px; font-size: 20px; }
.principle p { margin: 0; color: var(--ink-dim); font-size: 13.5px; }

/* ---- access ---- */
.access { padding: 112px 0; }
.access .grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.access h2 { font-size: 40px; line-height: 1.08; margin: 18px 0 20px; }
.access p { color: var(--ink-dim); font-size: 15px; }
.form { border: 1px solid var(--line); background: var(--bg-raised); padding: 24px; }
.form label { display: block; font-size: 11px; letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-dim); margin-bottom: 8px; }
.form input, .form textarea {
  width: 100%; background: var(--bg); border: 1px solid var(--line); color: var(--ink);
  font: inherit; padding: 11px 12px; margin-bottom: 16px; outline: none;
}
.form input:focus, .form textarea:focus { border-color: var(--accent); }
.form textarea { min-height: 88px; resize: vertical; }
.form button { all: unset; cursor: pointer; }
.form .btn { width: 100%; text-align: center; }
.form .note { margin: 14px 0 0; font-size: 11.5px; color: var(--ink-faint); }

/* ---- footer ---- */
footer { padding: 36px 0 48px; font-size: 11.5px; color: var(--ink-faint); }
footer .wrap { display: flex; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
footer a { color: var(--ink-dim); }
footer .cols { display: flex; gap: 32px; }

/* ---- responsive ---- */
@media (max-width: 900px) {
  section { padding: 72px 0; }
  .hero { padding: 72px 0; }
  .hero .grid, .math-grid, .access .grid, .section-head { grid-template-columns: 1fr; gap: 36px; }
  .math-grid { grid-template-columns: minmax(0, 1fr); } /* a wide figure must not stretch the stacked formula column */
  .strip .wrap { grid-template-columns: 1fr 1fr; }
  .strip .cell:nth-child(3) { border-left: 0; padding-left: 0; }
  .principles { grid-template-columns: 1fr; }
  .nav { display: none; }
}
@media (max-width: 560px) {
  .strip .wrap { grid-template-columns: 1fr; }
  .strip .cell { border-left: 0; padding-left: 0; }
  .status { display: none; }
  .topbar-right { gap: 0; }
  .formula { font-size: 24px; padding: 20px; }
  .figure .legend > span { white-space: normal; } /* long legend entries wrap instead of forcing a horizontal scroll */
}