/* =============================================================
   SS Sigma — Working Paper stylesheet.
   Typesets the page as a printed academic preprint.
   ============================================================= */

/* ─── Tokens ─────────────────────────────────────────────────── */
:root {
  /* paper tones — switchable via data-tone */
  --paper:         #F3EEDA;  /* warm cream */
  --paper-deep:    #E8DFC2;
  --paper-edge:    #DCD3B7;

  /* ink — switchable via data-ink */
  --ink:           #1B1813;
  --ink-soft:      #4C463C;
  --ink-faint:     #8E8675;

  /* marks */
  --rule:          rgba(27, 24, 19, 0.85);
  --rule-soft:     rgba(27, 24, 19, 0.20);
  --rule-faint:    rgba(27, 24, 19, 0.10);
  --mark:          #B83A2E;       /* red marker pen */
  --mark-deep:     #8C2A1F;
  --mark-soft:     rgba(184, 58, 46, 0.10);
  --highlight:     #F0D55E;        /* yellow highlighter */

  --ff-body:    "Crimson Pro", "STIX Two Text", "Source Serif 4", Georgia, serif;
  --ff-mono:    "JetBrains Mono", ui-monospace, monospace;

  --col-main:    640px;     /* body text column */
  --col-margin:  200px;     /* marginalia gutter */
  --col-gap:     56px;

  --type-body:   17px;
  --type-lead:   18px;
  --type-small:  13px;
  --type-tiny:   11px;

  --pad-side:    32px;
}

[data-tone="pristine"]  { --paper: #F8F5EC; --paper-deep: #EDE8D9; --paper-edge: #DDD6BF; }
[data-tone="vellum"]    { --paper: #EDE3BD; --paper-deep: #E0D49E; --paper-edge: #CFC086; }
[data-tone="blueprint"] {
  --paper: #1E3A52; --paper-deep: #173049; --paper-edge: #112739;
  --ink: #EDE3BD; --ink-soft: #C1B79A; --ink-faint: #8A8268;
  --rule: rgba(237, 227, 189, 0.85); --rule-soft: rgba(237, 227, 189, 0.22); --rule-faint: rgba(237, 227, 189, 0.10);
  --mark: #F0D55E;       /* gold marks on blueprint */
  --mark-deep: #DFB73C;
  --mark-soft: rgba(240, 213, 94, 0.14);
}
[data-ink="sepia"]   { --ink: #3D2B16; --ink-soft: #6A4F2C; --ink-faint: #9C8460; --rule: rgba(61, 43, 22, 0.85); --rule-soft: rgba(61, 43, 22, 0.20); --rule-faint: rgba(61, 43, 22, 0.10); }
[data-ink="indigo"]  { --ink: #1B2547; --ink-soft: #3F4A78; --ink-faint: #7682A8; --rule: rgba(27, 37, 71, 0.85); --rule-soft: rgba(27, 37, 71, 0.22); --rule-faint: rgba(27, 37, 71, 0.10); }

[data-density="journal"] {
  --type-body: 15px;
  --type-lead: 16px;
  --type-small: 12px;
  --col-main: 580px;
}

/* ─── Reset, base ────────────────────────────────────────────── */
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
html { background: var(--paper); }
body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--ff-body);
  font-size: var(--type-body);
  line-height: 1.55;
  font-feature-settings: "kern", "liga", "onum", "ss01";
  /* paper texture: faint grain via two layered radial-gradients */
  background-image:
    radial-gradient(ellipse at 30% 12%, var(--paper-deep) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 88%, var(--paper-edge) 0%, transparent 55%);
  background-attachment: fixed;
  text-rendering: geometricPrecision;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: var(--ink); text-decoration: underline; text-decoration-thickness: 0.5px; text-underline-offset: 2px; text-decoration-color: var(--rule-soft); }
a:hover { color: var(--mark); text-decoration-color: var(--mark); }

::selection { background: var(--highlight); color: var(--ink); }

/* ─── Running header (fixed at top) ──────────────────────────── */
.run-head {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 20;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  padding: 12px 28px;
  font-family: var(--ff-mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-soft);
  background: color-mix(in oklab, var(--paper) 92%, transparent);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--rule-soft);
}
.run-head .run-title { text-align: center; font-style: italic; font-family: var(--ff-body); font-size: 13px; letter-spacing: 0; text-transform: none; color: var(--ink); }
.run-head .run-page { text-align: right; }
.run-head .run-id   { text-align: left; }

/* ─── Compile splash ─────────────────────────────────────────── */
#compile-splash {
  position: fixed;
  inset: 0;
  background: var(--paper);
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  transition: opacity 600ms ease, visibility 600ms;
}
#compile-splash.gone { opacity: 0; visibility: hidden; pointer-events: none; }
.compile-log {
  font-family: var(--ff-mono);
  font-size: 12px;
  line-height: 1.55;
  color: var(--ink-soft);
  margin: 0;
  max-width: 720px;
  white-space: pre-wrap;
}
.compile-log .cli   { color: var(--ink); }
.compile-log .ok    { color: var(--mark-deep); }
.compile-log .hint  { color: var(--ink-faint); margin-top: 18px; font-style: italic; }
.compile-cursor::after { content: "█"; animation: caret 800ms steps(2) infinite; color: var(--ink); }
@keyframes caret { 50% { opacity: 0; } }

/* ─── Paper layout ───────────────────────────────────────────── */
.paper {
  padding: 96px 24px 80px;
  /* Two columns: main text + right margin gutter. */
}
.paper-row {
  display: grid;
  grid-template-columns:
    1fr
    min(var(--col-main), calc(100vw - 2 * var(--pad-side)))
    var(--col-margin)
    1fr;
  column-gap: var(--col-gap);
  margin-bottom: 1.4em;
}
.paper-row > .main   { grid-column: 2; }
.paper-row > .margin { grid-column: 3; align-self: start; }
.paper-row.wide > .main { grid-column: 2 / 4; }
.paper-row.center > .main { grid-column: 2 / 4; text-align: center; }

@media (max-width: 1000px) {
  :root { --col-main: 560px; --col-margin: 0px; --col-gap: 0px; }
  .paper-row { grid-template-columns: 1fr min(var(--col-main), calc(100vw - 2 * var(--pad-side))) 1fr; }
  .paper-row > .main   { grid-column: 2; }
  .paper-row > .margin {
    grid-column: 2;
    margin: 8px 0 18px;
    padding: 10px 14px;
    border-left: 2px solid var(--mark);
    background: var(--mark-soft);
  }
}
@media (min-width: 1001px) and (max-width: 1199px) {
  :root { --col-main: 540px; --col-margin: 180px; --col-gap: 32px; }
}
@media (max-width: 640px) {
  :root { --type-body: 16px; }
  .paper { padding-top: 88px; }
}

/* ─── Title block ────────────────────────────────────────────── */
.doc-class {
  font-family: var(--ff-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--ink-soft);
  text-transform: uppercase;
  margin: 0 0 36px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule-soft);
}
.paper-title {
  font-family: var(--ff-body);
  font-weight: 600;
  font-size: clamp(40px, 6.5vw, 84px);
  line-height: 1.02;
  letter-spacing: -0.012em;
  margin: 0 0 32px;
  color: var(--ink);
  text-wrap: balance;
}
.paper-title em {
  font-style: italic;
  font-weight: 500;
}
.paper-title sup {
  font-size: 0.42em;
  color: var(--mark);
  vertical-align: super;
  font-style: normal;
  font-weight: 500;
  margin-left: 0.1em;
}
.paper-title sup a.brochure-star {
  text-decoration: none;
  color: var(--mark);
  transition: color 200ms, transform 200ms;
  display: inline-block;
}
.paper-title sup a.brochure-star:hover {
  color: var(--mark-deep);
  transform: scale(1.18) rotate(-8deg);
}
.brochure-note {
  font-family: var(--ff-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--ink-faint);
  margin: 18px 0 0;
}
.brochure-note em {
  font-family: var(--ff-body);
  font-style: italic;
  font-size: 13.5px;
  letter-spacing: 0;
  color: var(--ink-soft);
}
.brochure-note a {
  color: var(--mark);
  text-decoration: underline;
  text-decoration-thickness: 0.5px;
  text-underline-offset: 2px;
  text-decoration-color: var(--mark-soft);
}
.brochure-note a:hover {
  color: var(--mark-deep);
  text-decoration-color: var(--mark);
}
.title-rule {
  width: 64px;
  height: 1px;
  background: var(--ink);
  margin: 32px 0 28px;
}
.authors {
  font-variant: small-caps;
  font-weight: 500;
  letter-spacing: 0.04em;
  font-size: 17px;
  color: var(--ink);
  margin: 0 0 4px;
  line-height: 1.35;
}
.affil {
  font-style: italic;
  color: var(--ink-soft);
  font-size: 15px;
  margin: 0 0 4px;
  line-height: 1.4;
}
.cred {
  font-family: var(--ff-mono);
  font-size: 11px;
  color: var(--ink-soft);
  letter-spacing: 0.05em;
  margin: 18px 0 0;
}
.dates {
  font-family: var(--ff-mono);
  font-size: 11px;
  color: var(--ink-faint);
  letter-spacing: 0.05em;
  margin: 28px 0 0;
}

/* ─── Abstract ───────────────────────────────────────────────── */
.abstract {
  margin-top: 56px;
  padding: 28px 0 0;
  border-top: 1px solid var(--rule);
}
.abstract-head, .keywords-head, .sec-head, .subsec-head, .ref-head {
  font-family: var(--ff-body);
  color: var(--ink);
}
.abstract-head, .keywords-head {
  font-weight: 600;
  font-size: 16px;
  font-variant: small-caps;
  letter-spacing: 0.08em;
  margin: 0 0 14px;
}
.abstract p {
  font-size: 15.5px;
  line-height: 1.6;
  text-align: justify;
  hyphens: auto;
  margin: 0 0 0.9em;
  color: var(--ink);
}
.keywords {
  margin-top: 28px;
  font-size: 14px;
  color: var(--ink-soft);
  line-height: 1.55;
}
.keywords-head { display: inline; margin-right: 8px; }
.keywords em { font-style: italic; color: var(--ink); }

/* ─── Section heads ──────────────────────────────────────────── */
.sec-head {
  font-weight: 600;
  font-size: clamp(24px, 3vw, 32px);
  letter-spacing: -0.005em;
  line-height: 1.15;
  margin: 64px 0 20px;
  color: var(--ink);
  scroll-margin-top: 80px;
}
.sec-head .sec-num {
  color: var(--ink-faint);
  font-weight: 500;
  font-style: italic;
  margin-right: 14px;
  letter-spacing: 0;
}
.subsec-head {
  font-weight: 600;
  font-size: 17px;
  font-variant: small-caps;
  letter-spacing: 0.04em;
  margin: 32px 0 10px;
  color: var(--ink);
  scroll-margin-top: 80px;
}
.subsec-head .sec-num {
  color: var(--ink-faint);
  font-weight: 500;
  font-style: italic;
  margin-right: 8px;
  letter-spacing: 0;
  font-variant: normal;
  display: inline-block;
}

/* ─── Body type ─────────────────────────────────────────────── */
.paper p {
  margin: 0 0 0.85em;
  text-align: justify;
  hyphens: auto;
}
.paper p.lead::first-letter {
  font-family: var(--ff-body);
  font-weight: 600;
  font-size: 4.4em;
  float: left;
  line-height: 0.86;
  margin: 0.06em 0.08em -0.05em 0;
  color: var(--ink);
}
.paper p em { font-style: italic; }
.paper p strong { font-weight: 600; }

/* highlighter — used on rare key phrases */
.hl {
  background-image: linear-gradient(180deg, transparent 56%, var(--highlight) 56%, var(--highlight) 92%, transparent 92%);
  padding: 0 2px;
}

/* ─── Footnotes ──────────────────────────────────────────────── */
.fn {
  font-family: var(--ff-mono);
  font-size: 0.62em;
  vertical-align: super;
  color: var(--mark);
  text-decoration: none;
  margin-left: 0.06em;
  padding: 0 2px;
  border-radius: 2px;
  transition: background 160ms;
}
.fn:hover { background: var(--mark-soft); color: var(--mark-deep); }

.fn-pop {
  position: fixed;
  z-index: 30;
  max-width: 320px;
  background: var(--paper);
  border: 1px solid var(--rule);
  box-shadow: 0 12px 32px -8px rgba(27,24,19,0.25);
  padding: 14px 16px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--ink);
  pointer-events: none;
  opacity: 0;
  transform: translateY(-4px);
  transition: opacity 180ms, transform 180ms;
}
.fn-pop.show { opacity: 1; transform: none; pointer-events: auto; }
.fn-pop .ref { font-family: var(--ff-mono); color: var(--mark); font-size: 11px; letter-spacing: 0.06em; margin-bottom: 4px; }

/* ─── Margin notes ───────────────────────────────────────────── */
.margin {
  font-size: 12.5px;
  line-height: 1.45;
  color: var(--ink-soft);
  font-style: italic;
  font-family: var(--ff-body);
  padding-top: 4px;
}
.margin .m-tag {
  display: block;
  font-family: var(--ff-mono);
  font-style: normal;
  font-size: 9.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mark);
  margin-bottom: 6px;
}
.margin .m-eqn {
  display: block;
  font-family: var(--ff-mono);
  font-style: normal;
  font-size: 12px;
  color: var(--ink);
  padding: 4px 0;
}
.margin .m-red {
  color: var(--mark);
  font-family: var(--ff-body);
  font-style: italic;
  display: block;
  padding: 4px 0;
  position: relative;
}
.margin .m-red::before {
  content: "↳ ";
  font-family: var(--ff-mono);
  font-style: normal;
}

/* ─── Display equations ─────────────────────────────────────── */
.eqn-block {
  text-align: center;
  margin: 24px 0 28px;
}
.eqn-block .eqn-label {
  float: right;
  font-family: var(--ff-mono);
  font-size: 12px;
  color: var(--ink-faint);
  margin-top: 12px;
}
.katex { color: var(--ink) !important; font-size: 1.06em !important; }
.katex-display { margin: 0 !important; }

/* ─── Proposition box ────────────────────────────────────────── */
.prop {
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  padding: 22px 0 24px;
  margin: 28px 0;
}
.prop-head {
  font-family: var(--ff-body);
  font-weight: 600;
  font-size: 15px;
  font-variant: small-caps;
  letter-spacing: 0.06em;
  margin: 0 0 14px;
  color: var(--ink);
}
.prop-head em { font-style: italic; font-variant: normal; font-weight: 500; }
.prop p {
  font-size: 15.5px;
  line-height: 1.6;
  margin: 0 0 0.85em;
}
.prop p:last-child { margin-bottom: 0; }

/* ─── Table (booktabs style) ─────────────────────────────────── */
.tbl-wrap { margin: 28px 0; }
.tbl-cap {
  font-size: 13px;
  color: var(--ink-soft);
  margin-bottom: 10px;
  font-style: italic;
}
.tbl-cap b { font-style: normal; font-weight: 600; color: var(--ink); margin-right: 4px; }
table.book {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  line-height: 1.4;
  border-spacing: 0;
}
table.book thead th {
  text-align: left;
  font-weight: 600;
  font-style: italic;
  padding: 14px 12px 10px;
  border-top: 1.5px solid var(--ink);
  border-bottom: 0.5px solid var(--ink);
  color: var(--ink);
  vertical-align: bottom;
}
table.book tbody td {
  padding: 14px 12px;
  vertical-align: top;
  color: var(--ink);
  border-bottom: 1px solid var(--rule-faint);
}
table.book tbody tr:last-child td {
  border-bottom: 1.5px solid var(--ink);
}
table.book tbody td .row-tag {
  font-style: italic;
  color: var(--ink-soft);
  display: block;
  font-size: 12px;
  margin-bottom: 4px;
  font-family: var(--ff-mono);
  font-variant: normal;
  letter-spacing: 0.04em;
}

/* ─── Results blocks ─────────────────────────────────────────── */
.result {
  margin: 24px 0;
  padding: 22px 0;
  border-top: 0.5px solid var(--rule);
}
.result:last-of-type { border-bottom: 0.5px solid var(--rule); }
.result-head {
  font-family: var(--ff-body);
  font-weight: 600;
  font-size: 15px;
  font-variant: small-caps;
  letter-spacing: 0.06em;
  margin: 0 0 12px;
  color: var(--ink);
}
.result-head em { font-style: italic; font-variant: normal; font-weight: 500; }
.metric {
  display: inline-block;
  padding: 0 4px;
  border-bottom: 2px solid var(--mark);
  font-weight: 500;
  color: var(--ink);
  white-space: nowrap;
}
.metric.struck {
  position: relative;
  text-decoration: none;
  padding-right: 6px;
}
.metric.struck::after {
  content: "";
  position: absolute;
  left: 0; right: 0; top: 50%;
  height: 1.5px;
  background: var(--mark);
  transform: rotate(-3deg);
}

/* ─── References ─────────────────────────────────────────────── */
.refs {
  margin: 64px 0 24px;
  padding-top: 24px;
  border-top: 1px solid var(--rule);
}
.refs h2 {
  font-family: var(--ff-body);
  font-weight: 600;
  font-size: 16px;
  font-variant: small-caps;
  letter-spacing: 0.06em;
  margin: 0 0 16px;
  color: var(--ink);
}
.refs ol {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: ref;
}
.refs li {
  counter-increment: ref;
  position: relative;
  padding-left: 32px;
  margin-bottom: 10px;
  font-size: 13.5px;
  line-height: 1.5;
  color: var(--ink-soft);
  text-align: justify;
  hyphens: auto;
}
.refs li::before {
  content: "[" counter(ref) "]";
  position: absolute;
  left: 0;
  font-family: var(--ff-mono);
  font-size: 11px;
  color: var(--ink-faint);
  top: 2px;
}
.refs li i, .refs li em { font-style: italic; color: var(--ink); }

.ack {
  margin-top: 28px;
  font-size: 13.5px;
  font-style: italic;
  color: var(--ink-soft);
}

/* ─── Footer ─────────────────────────────────────────────────── */
.paper-foot {
  margin-top: 96px;
  padding-bottom: 56px;
}
.paper-foot .main {
  border-top: 1px solid var(--rule-soft);
  padding-top: 18px;
  font-family: var(--ff-mono);
  font-size: 10.5px;
  letter-spacing: 0.05em;
  color: var(--ink-faint);
  display: flex;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

/* ─── Inline status badge (e.g. "[product · in build]") ──── */
.subsec-head .badge {
  font-family: var(--ff-mono);
  font-variant: normal;
  font-style: normal;
  font-size: 10px;
  letter-spacing: 0.10em;
  color: var(--mark);
  text-transform: uppercase;
  margin-left: 10px;
  font-weight: 500;
  border: 1px solid var(--mark);
  border-radius: 2px;
  padding: 1px 6px;
  vertical-align: 2px;
  white-space: nowrap;
}
.subsec-head .badge.stable {
  color: var(--ink-soft);
  border-color: var(--rule-soft);
}

/* ─── Cross-link to the brochure edition ─────────────────── */
.brochure-pill {
  position: fixed;
  bottom: 22px;
  right: 22px;
  z-index: 50;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 18px 10px 14px;
  background: color-mix(in oklab, var(--paper) 88%, transparent);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--rule);
  border-radius: 999px;
  font-family: var(--ff-body);
  font-style: italic;
  font-size: 14px;
  color: var(--ink);
  text-decoration: none;
  box-shadow: 0 6px 20px -8px rgba(27, 24, 19, 0.18);
  /* slide in after splash dismisses */
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 600ms ease, transform 600ms ease, border-color 240ms ease, gap 240ms ease;
  pointer-events: none;
}
.brochure-pill.in {
  opacity: 1;
  transform: none;
  pointer-events: auto;
}
.brochure-pill .star {
  color: var(--mark);
  font-style: normal;
  font-size: 15px;
  line-height: 1;
  letter-spacing: 0;
}
.brochure-pill .arrow {
  font-family: var(--ff-mono);
  font-style: normal;
  color: var(--mark);
  font-size: 13px;
  transition: transform 240ms ease;
}
.brochure-pill:hover {
  border-color: var(--mark);
  gap: 14px;
}
.brochure-pill:hover .arrow { transform: translate(2px, -2px); }

/* On small screens, tuck it tighter */
@media (max-width: 640px) {
  .brochure-pill {
    bottom: 14px; right: 14px;
    padding: 8px 14px 8px 12px;
    font-size: 12.5px;
  }
}

/* ─── Σ scribble (annotation accent) ──────────────────────── */
.scribble {
  text-decoration: underline wavy var(--mark);
  text-decoration-thickness: 1.2px;
  text-underline-offset: 5px;
}

/* ─── Σ frontispiece (one big mathematical glyph) ─────────── */
.sigma-frontis {
  text-align: center;
  margin: 40px 0 32px;
  font-family: var(--ff-body);
  font-weight: 500;
}
.sigma-frontis .sig {
  font-size: 220px;
  font-style: italic;
  line-height: 0.86;
  display: inline-block;
  color: var(--ink);
}
.sigma-frontis .sub {
  display: block;
  font-family: var(--ff-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--ink-faint);
  margin-top: 12px;
  text-transform: uppercase;
}

@media (max-width: 640px) {
  .sigma-frontis .sig { font-size: 140px; }
}

/* ─── Focus ──────────────────────────────────────────────────── */
:focus-visible {
  outline: 1.5px dashed var(--mark);
  outline-offset: 4px;
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}