/* ============================================================
   SPHR Whitepaper — Liber TAU Reading Room (hero-v3 P2)
   Long-read surface: Inter 19px/1.8, ≤70ch, fixed lateral TOC.
   ============================================================ */
:root {
  --bg: #05070c;
  --bg-soft: #0a0e16;
  --ink: #d8dde6;
  --ink-dim: #8b93a3;
  --gold: #ffd700;
  --gold-soft: rgba(255, 215, 0, 0.14);
  --blue: #1e6fff;
  --line: rgba(216, 221, 230, 0.12);
  --opset: #ffb84a;
  --measure: 70ch;
}

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

html { scroll-behavior: smooth; scroll-padding-top: 84px; }

body {
  background:
    radial-gradient(1100px 500px at 85% -10%, rgba(30, 111, 255, 0.07), transparent 60%),
    radial-gradient(900px 480px at -10% 8%, rgba(255, 215, 0, 0.05), transparent 55%),
    var(--bg);
  color: var(--ink);
  font-family: 'Inter', system-ui, sans-serif;
  font-size: 19px;
  line-height: 1.8;
  font-weight: 300;
}

/* ===== chrome ===== */
.chrome {
  position: fixed; inset: 0 0 auto 0; z-index: 40;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 22px;
  background: linear-gradient(180deg, rgba(5, 7, 12, 0.92), rgba(5, 7, 12, 0.75) 70%, transparent);
  backdrop-filter: blur(8px);
}
.chrome a {
  color: var(--ink-dim); text-decoration: none;
  font-family: 'Barlow', sans-serif; font-size: 14px; font-weight: 600;
  letter-spacing: 0.08em; text-transform: uppercase;
  padding: 8px 10px; min-height: 44px; display: inline-flex; align-items: center;
  transition: color 0.25s;
}
.chrome a:hover, .chrome a:focus-visible { color: var(--gold); }
.chrome-mid { display: flex; gap: 6px; }

/* ===== layout ===== */
.wrap { display: flex; max-width: 1280px; margin: 0 auto; padding: 120px 24px 80px; gap: 48px; }

/* ===== TOC ===== */
.toc {
  position: sticky; top: 96px; align-self: flex-start;
  width: 250px; flex: none;
  max-height: calc(100vh - 130px); overflow-y: auto;
  font-family: 'Barlow', sans-serif; font-size: 13.5px;
  border-left: 1px solid var(--line); padding-left: 4px;
}
.toc-head {
  font-size: 11px; letter-spacing: 0.22em; text-transform: uppercase;
  color: var(--ink-dim); padding: 6px 14px 10px;
}
.toc a {
  display: block; color: var(--ink-dim); text-decoration: none;
  padding: 7px 14px; border-left: 2px solid transparent; margin-left: -5px;
  letter-spacing: 0.02em; transition: color 0.2s, border-color 0.2s;
}
.toc a.sub { padding-left: 28px; font-size: 12.5px; }
.toc a:hover, .toc a:focus-visible { color: var(--ink); }
.toc a.on { color: var(--gold); border-left-color: var(--gold); }
.toc-soon {
  margin-top: 14px; padding: 10px 14px; border-top: 1px dashed var(--line);
  color: var(--ink-dim); font-size: 12px;
}
.toc-soon .th { letter-spacing: 0.18em; text-transform: uppercase; font-size: 10.5px; opacity: 0.8; }
.toc-soon .ti { display: block; padding: 4px 0 0; opacity: 0.55; font-style: italic; }
.toc-soon .ti::after { content: " ·"; color: var(--opset); font-style: normal; }

/* ===== paper ===== */
.paper { min-width: 0; max-width: var(--measure); }

.p-eyebrow {
  font-family: 'JetBrains Mono', monospace; font-size: 12px;
  letter-spacing: 0.28em; text-transform: uppercase; color: var(--gold);
}
h1 {
  font-family: 'Cinzel', serif; font-weight: 700; color: #fff;
  font-size: clamp(34px, 5vw, 52px); line-height: 1.15; margin: 10px 0 18px;
}
.p-meta {
  display: flex; flex-wrap: wrap; gap: 8px; margin: 4px 0 12px;
  font-family: 'JetBrains Mono', monospace; font-size: 12px; color: var(--ink-dim);
}
.p-meta span {
  border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px;
  background: var(--bg-soft);
}
.p-note {
  font-size: 15px; color: var(--ink-dim); border-left: 2px solid var(--gold-soft);
  padding: 6px 0 6px 16px; margin: 14px 0 8px;
}

section { padding: 34px 0 6px; }
h2 {
  font-family: 'Cinzel', serif; font-weight: 600; color: #fff;
  font-size: clamp(24px, 3.2vw, 32px); line-height: 1.25;
  margin: 0 0 16px; padding-top: 18px; border-top: 1px solid var(--line);
}
h3 {
  font-family: 'Barlow', sans-serif; font-weight: 700; color: var(--gold);
  font-size: 19px; letter-spacing: 0.03em; margin: 26px 0 10px;
}
p { margin: 0 0 18px; }
strong { color: #fff; font-weight: 600; }
em { color: var(--ink); }
ul { margin: 0 0 18px 22px; }
li { margin-bottom: 10px; }

code, .opset {
  font-family: 'JetBrains Mono', monospace; font-size: 0.82em;
  background: var(--bg-soft); border: 1px solid var(--line);
  border-radius: 5px; padding: 1px 7px;
}
.opset { color: var(--opset); border-color: rgba(255, 184, 74, 0.35); white-space: nowrap; }

blockquote {
  margin: 22px 0; padding: 18px 22px;
  border-left: 3px solid var(--gold);
  background: linear-gradient(90deg, var(--gold-soft), transparent 70%);
  border-radius: 0 10px 10px 0; color: #fff; font-weight: 400;
}

/* ===== tables ===== */
.tbl-scroll { overflow-x: auto; margin: 4px 0 22px; }
table {
  border-collapse: collapse; width: 100%; min-width: 520px;
  font-size: 15.5px; line-height: 1.5;
}
th, td { border: 1px solid var(--line); padding: 10px 14px; text-align: left; vertical-align: top; }
th {
  font-family: 'Barlow', sans-serif; font-size: 12.5px; font-weight: 700;
  letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--gold); background: var(--bg-soft);
}
td strong { white-space: nowrap; }

/* ===== footer ===== */
.paper-foot {
  margin-top: 56px; padding-top: 24px; border-top: 1px solid var(--line);
  font-size: 14px; color: var(--ink-dim);
}
.foot-links {
  display: flex; flex-wrap: wrap; gap: 4px 10px; align-items: center;
  font-family: 'Barlow', sans-serif; font-size: 14px; margin-bottom: 14px;
}
.foot-links a {
  color: var(--ink-dim); text-decoration: none; padding: 8px 4px; min-height: 44px;
  display: inline-flex; align-items: center; transition: color 0.25s;
}
.foot-links a:hover, .foot-links a:focus-visible { color: var(--gold); }
.fsep { opacity: 0.5; }
.foot-brand {
  font-family: 'Fredericka the Great', cursive; font-size: 15px;
  color: var(--ink-dim); margin-top: 10px;
}

/* ===== responsive ===== */
@media (max-width: 960px) {
  .wrap { flex-direction: column; padding-top: 96px; gap: 20px; }
  .toc {
    position: static; width: 100%; max-height: none;
    border-left: none; border: 1px solid var(--line); border-radius: 12px;
    padding: 10px 6px; background: var(--bg-soft);
    columns: 2; column-gap: 8px;
  }
  .toc-head, .toc-soon { column-span: all; }
  .toc a { margin-left: 0; border-left: none; }
  .toc a.on { color: var(--gold); }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}