@import url('https://fonts.googleapis.com/css2?family=Fraunces:opsz,wght@9..144,400;9..144,500;9..144,600;9..144,400&family=IBM+Plex+Mono:wght@400;500;600&family=IBM+Plex+Sans:wght@300;400;500;600&display=swap');

/* ── tokens ───────────────────────────────────────────────────── */
:root {
  --paper:       #F4F1EA;
  --paper-card:  #FBF9F4;
  --ink:         #1B1813;
  --ink-2:       #544E46;
  --ink-3:       #8B8377;
  --rule:        #DCD5C8;
  --rule-strong: #C3BAAA;
  --accent:      #B23A1E;
  --accent-soft: rgba(178,58,30,.10);
  --serif: 'Fraunces', Georgia, 'Times New Roman', serif;
  --sans:  'IBM Plex Sans', system-ui, -apple-system, sans-serif;
  --mono:  'IBM Plex Mono', ui-monospace, Menlo, monospace;
  --maxw: 1100px;
  --gutter: clamp(1.25rem, 5vw, 4rem);
  --ease: cubic-bezier(.2,.6,.2,1);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  font-family: var(--sans);
  background: var(--paper);
  color: var(--ink);
  line-height: 1.7;
  font-weight: 400;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
::selection { background: var(--accent); color: var(--paper); }

a { color: inherit; text-decoration: none; }
code { font-family: var(--mono); font-size: .82em; background: var(--accent-soft); color: #8a2c14; padding: .08em .34em; border-radius: 2px; overflow-wrap: anywhere; }
em { font-style: italic; }
.run { font-family: var(--mono); font-size: .82em; background: var(--accent-soft); color: #8a2c14; padding: .1em .4em; border-radius: 2px; }
.ul { background-image: linear-gradient(var(--accent), var(--accent)); background-size: 100% 1px; background-repeat: no-repeat; background-position: 0 1.05em; }

/* shared label style */
.kicker, .svc-no, .masthead-nav a, .nav-repo, .logo-text, .cover-figures dt,
.dossier dt, .stack-list dt, .footer-micro, .footer-links a, .c-no, .figcaption,
.d-cap, .contents .c-desc { font-family: var(--mono); }

/* ── reading progress ─────────────────────────────────────────── */
.reading-bar { position: fixed; top: 0; left: 0; height: 2px; width: 0; background: var(--accent); z-index: 200; transition: width .1s linear; }

/* ── masthead ─────────────────────────────────────────────────── */
.masthead {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 1rem var(--gutter);
  background: color-mix(in srgb, var(--paper) 86%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--rule);
}
.logo { display: inline-flex; align-items: center; gap: .6rem; color: var(--ink); }
.logo-mark { color: var(--accent); flex: none; }
.logo-text { font-size: .82rem; font-weight: 500; letter-spacing: .06em; text-transform: uppercase; }
.masthead-nav { display: flex; align-items: center; gap: 1.8rem; }
.masthead-nav a { font-size: .76rem; letter-spacing: .05em; text-transform: uppercase; color: var(--ink-2); position: relative; padding: .2rem 0; transition: color .2s var(--ease); }
.masthead-nav a:hover, .masthead-nav a.active { color: var(--ink); }
.masthead-nav a[data-nav]::after { content:''; position:absolute; left:0; bottom:-2px; height:1px; width:0; background:var(--accent); transition:width .25s var(--ease); }
.masthead-nav a[data-nav]:hover::after, .masthead-nav a[data-nav].active::after { width:100%; }
.nav-repo { color: var(--ink) !important; }
@media (max-width: 680px) { .masthead-nav { gap: 1.1rem; } .masthead-nav a:not(.nav-repo) { display: none; } .logo-text { display: none; } }

/* ── layout helpers ───────────────────────────────────────────── */
section { padding: 0 var(--gutter); }
.svc-no { font-size: .76rem; letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }

/* ── cover ────────────────────────────────────────────────────── */
.cover { max-width: var(--maxw); margin: 0 auto; padding-top: clamp(3.5rem, 9vw, 7rem); padding-bottom: clamp(3rem, 7vw, 5.5rem); }
.kicker { font-size: .8rem; letter-spacing: .18em; text-transform: uppercase; color: var(--ink-3); }
.cover-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(3rem, 9.5vw, 7.2rem);
  line-height: .98;
  letter-spacing: -.02em;
  margin: 1.4rem 0 0;
  font-optical-sizing: auto;
}
.cover-title em { font-style: italic; font-weight: 400; color: var(--accent); }
.cover-meta { display: grid; grid-template-columns: 1.4fr 1fr; gap: clamp(1.5rem, 5vw, 4rem); margin-top: 2.6rem; padding-top: 2.2rem; border-top: 1px solid var(--rule); }
.cover-lede { font-size: 1.18rem; line-height: 1.65; color: var(--ink-2); max-width: 46ch; }
.cover-lede .ul { color: var(--ink); }
.cover-figures { display: grid; grid-template-columns: 1fr 1fr; gap: 1.1rem 1.6rem; align-content: start; }
.cover-figures div { border-top: 1px solid var(--rule); padding-top: .5rem; }
.cover-figures dt { font-size: .68rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-3); }
.cover-figures dd { font-family: var(--serif); font-size: 2.4rem; font-weight: 500; line-height: 1.1; margin-top: .1rem; }
.cover-figures .pct { font-size: 1.3rem; color: var(--ink-3); }
@media (max-width: 720px){ .cover-meta { grid-template-columns: 1fr; } }

/* contents / table of contents */
.contents { list-style: none; margin-top: 3rem; border-top: 1.5px solid var(--ink); }
.contents li { border-bottom: 1px solid var(--rule); }
.contents a { display: grid; grid-template-columns: 3rem minmax(8rem, 1fr) 2fr auto; align-items: baseline; gap: 1.2rem; padding: 1.1rem .2rem; transition: background .25s var(--ease), padding-left .25s var(--ease); }
.contents a:hover { background: var(--paper-card); padding-left: .9rem; }
.c-no { font-size: .82rem; color: var(--ink-3); }
.c-name { font-family: var(--serif); font-size: 1.6rem; font-weight: 500; letter-spacing: -.01em; }
.c-desc { font-size: .8rem; letter-spacing: .02em; color: var(--ink-2); text-transform: none; }
.c-go { font-family: var(--serif); font-size: 1.4rem; color: var(--rule-strong); justify-self: end; transition: color .25s var(--ease), transform .25s var(--ease); }
.contents a:hover .c-go { color: var(--accent); transform: translateX(4px); }
@media (max-width: 640px){
  .contents a { grid-template-columns: 2.2rem 1fr auto; }
  .c-desc { grid-column: 2 / -1; grid-row: 2; }
}

/* ── services ─────────────────────────────────────────────────── */
.svc { max-width: var(--maxw); margin: 0 auto; padding: clamp(3.5rem, 8vw, 6rem) 0; border-top: 1px solid var(--rule); }
.svc-masthead { display: flex; align-items: baseline; gap: 1.2rem; flex-wrap: wrap; margin-bottom: 2.6rem; }
.svc-masthead h2 { font-family: var(--serif); font-size: clamp(2.4rem, 6vw, 4rem); font-weight: 500; letter-spacing: -.02em; line-height: 1; }
.svc-sub { margin-left: auto; font-family: var(--mono); font-size: .74rem; letter-spacing: .14em; text-transform: uppercase; color: var(--ink-3); }
.svc-grid { display: grid; grid-template-columns: 240px 1fr; gap: clamp(1.5rem, 5vw, 4rem); }

.dossier { min-width: 0; }
.dossier dl { border-top: 1px solid var(--ink); }
.dossier div { display: flex; justify-content: space-between; gap: 1rem; padding: .6rem 0; border-bottom: 1px solid var(--rule); }
.dossier dt { font-size: .68rem; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); flex: none; padding-top: .15rem; }
.dossier dd { font-size: .9rem; text-align: right; color: var(--ink); }
.dossier-links { display: flex; flex-direction: column; gap: .5rem; margin-top: 1.4rem; }
.dossier-links a { font-family: var(--mono); font-size: .78rem; color: var(--ink-2); display: inline-flex; align-items: center; gap: .4rem; transition: color .2s var(--ease); width: fit-content; }
.dossier-links a::before { content: '→'; color: var(--accent); }
.dossier-links a:hover { color: var(--accent); }

.svc-body { min-width: 0; }
.svc-lead { font-family: var(--serif); font-size: clamp(1.35rem, 2.6vw, 1.75rem); font-weight: 400; line-height: 1.42; letter-spacing: -.01em; color: var(--ink); margin-bottom: 1.8rem; }
.svc-lead strong { font-weight: 600; }
.svc-lead em { color: var(--accent); }
.notes { list-style: none; counter-reset: note; margin-bottom: 2.4rem; }
.notes li { counter-increment: note; position: relative; padding: .9rem 0 .9rem 2.6rem; border-top: 1px solid var(--rule); color: var(--ink-2); font-size: .98rem; line-height: 1.62; }
.notes li::before { content: counter(note, decimal-leading-zero); position: absolute; left: 0; top: .95rem; font-family: var(--mono); font-size: .72rem; color: var(--accent); letter-spacing: .05em; }
.notes strong { color: var(--ink); font-weight: 600; }
.notes em { color: var(--ink); border-bottom: 1px solid var(--rule-strong); font-style: normal; }

/* ── figures (ink line-art) ───────────────────────────────────── */
.figure { border: 1px solid var(--rule-strong); background: var(--paper-card); padding: 1.4rem 1.4rem .9rem; }
.diagram { display: block; width: 100%; height: auto; color: var(--ink); }
.d-cap { font-size: 8.5px; font-weight: 600; letter-spacing: .08em; fill: var(--ink); }
.d-hash, .d-sub { font-family: var(--mono); font-size: 8px; fill: var(--ink-3); }
.d-mono { font-family: var(--mono); font-size: 9.5px; fill: var(--ink-2); }
.d-rule { stroke: var(--rule-strong); }
.d-on, .d-flag { fill: var(--accent); }
.d-band { fill: var(--accent-soft); }
.d-marker line { stroke: var(--accent); stroke-width: 1.25; }
.d-marker circle { fill: var(--accent); }
.d-bad rect, .d-bad line, .d-bad-line { stroke: var(--accent); }
.figcaption, figcaption { font-family: var(--mono); font-size: .72rem; color: var(--ink-3); margin-top: 1rem; padding-top: .7rem; border-top: 1px solid var(--rule); letter-spacing: .01em; }
@media (max-width: 760px){ .svc-grid { grid-template-columns: 1fr; } .svc-sub { margin-left: 0; } }

/* ── architecture ─────────────────────────────────────────────── */
.arch, .colophon { max-width: var(--maxw); margin: 0 auto; padding: clamp(3.5rem, 8vw, 6rem) 0; border-top: 1px solid var(--rule); }
.spread-head { margin-bottom: 2.8rem; }
.spread-head h2 { font-family: var(--serif); font-size: clamp(2.2rem, 5.5vw, 3.6rem); font-weight: 500; line-height: 1.02; letter-spacing: -.02em; margin-top: .6rem; }
.arch-cols { display: grid; grid-template-columns: 1fr 1fr; gap: 2.4rem 3.2rem; }
.arch-item h3 { font-family: var(--serif); font-size: 1.4rem; font-weight: 500; margin-bottom: .7rem; display: flex; gap: .5rem; align-items: baseline; flex-wrap: wrap; }
.arch-item p { color: var(--ink-2); font-size: .98rem; }
.arch-item strong { color: var(--ink); font-weight: 600; }
.arch-item em { color: var(--ink); }
.arch-diagram { margin-top: 3rem; padding: 1.8rem; border: 1px solid var(--rule-strong); background: var(--paper-card); }
.arch-diagram svg { width: 100%; height: auto; color: var(--ink); display: block; }
@media (max-width: 720px){ .arch-cols { grid-template-columns: 1fr; } }

/* ── colophon ─────────────────────────────────────────────────── */
.colophon-grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: clamp(1.5rem,5vw,4rem); }
.colo-prose p { color: var(--ink-2); font-size: 1.04rem; margin-bottom: 1.2rem; }
.colo-prose strong { color: var(--ink); font-weight: 600; }
.colo-set { font-family: var(--serif); font-size: 1.15rem; color: var(--ink) !important; }
.colo-set em { color: var(--accent); }
.colo-set a { border-bottom: 1px solid var(--accent); color: var(--accent); }
.stack-list dl, .stack-list { border-top: 1px solid var(--ink); }
.stack-list div { padding: .7rem 0; border-bottom: 1px solid var(--rule); }
.stack-list dt { font-size: .68rem; letter-spacing: .1em; text-transform: uppercase; color: var(--ink-3); margin-bottom: .15rem; }
.stack-list dd { font-family: var(--mono); font-size: .82rem; color: var(--ink); }
@media (max-width: 720px){ .colophon-grid { grid-template-columns: 1fr; } }

/* ── footer ───────────────────────────────────────────────────── */
.footer { max-width: var(--maxw); margin: 0 auto; padding: 0 var(--gutter); }
.footer-rule { border-top: 2px solid var(--ink); }
.footer-inner { display: flex; justify-content: space-between; align-items: center; gap: 1.5rem; padding: 1.8rem 0; flex-wrap: wrap; }
.logo-foot .logo-text { font-size: .8rem; }
.footer-links { display: flex; gap: 1.6rem; flex-wrap: wrap; }
.footer-links a { font-size: .74rem; letter-spacing: .04em; text-transform: uppercase; color: var(--ink-2); transition: color .2s var(--ease); }
.footer-links a:hover { color: var(--accent); }
.footer-micro { display: flex; justify-content: space-between; gap: 1rem; padding: 1rem 0 2.5rem; border-top: 1px solid var(--rule); font-size: .7rem; letter-spacing: .03em; text-transform: uppercase; color: var(--ink-3); flex-wrap: wrap; }

/* ── reveal ───────────────────────────────────────────────────── */
[data-reveal] { opacity: 0; transform: translateY(16px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
[data-reveal].in { opacity: 1; transform: none; }
[data-reveal][data-reveal-delay="1"] { transition-delay: .1s; }
[data-reveal][data-reveal-delay="2"] { transition-delay: .2s; }
[data-reveal][data-reveal-delay="3"] { transition-delay: .3s; }

@media (prefers-reduced-motion: reduce) {
  [data-reveal] { opacity: 1 !important; transform: none !important; transition: none !important; }
  .reading-bar { display: none; }
}