/* Writing: static pages generated by scripts/build-blog.mjs. Tokens mirror src/index.css. */

:root {
  --ink: #0a0a0a;
  --paper: #fafafa;
  --text: #d9d9d9;
  --steel: #a3a3a3;
  --graphite: #141414;
  --raised: #1b1b1b;
  --rule: #262626;
  --signal: #e31b23;
  --sans: 'Geist', ui-sans-serif, system-ui, -apple-system, 'Segoe UI', sans-serif;
  --mono: 'Geist Mono', ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
  --pad: clamp(1rem, 4vw, 3rem);
  --measure: 38rem;
  color-scheme: dark;
}

*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-padding-top: 88px; }

body {
  margin: 0;
  background: var(--ink);
  color: var(--text);
  font-family: var(--sans);
  font-size: 1.125rem;
  line-height: 1.7;
  font-feature-settings: 'ss01', 'cv11';
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection { background: var(--signal); color: #fff; }

a { color: inherit; }

:focus-visible { outline: 2px solid var(--signal); outline-offset: 3px; }

.skip-link {
  position: absolute;
  left: var(--pad);
  top: -100px;
  z-index: 20;
  padding: 0.6rem 1rem;
  background: var(--paper);
  color: var(--ink);
  font-size: 0.875rem;
  text-decoration: none;
}
.skip-link:focus { top: 1rem; }

/* Header, matching the site header */
.b-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--ink);
  border-bottom: 1px solid var(--rule);
}
.b-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  max-width: 1440px;
  height: 72px;
  margin: 0 auto;
  padding: 0 var(--pad);
}
.b-mark { color: var(--paper); font-weight: 700; font-size: 1.05rem; letter-spacing: -0.02em; text-decoration: none; }
.b-mark span { color: var(--signal); }
.b-nav { display: flex; gap: 1.75rem; }
.b-nav a {
  position: relative;
  color: var(--steel);
  font-size: 0.875rem;
  text-decoration: none;
  padding: 0.35rem 0;
}
.b-nav a:hover { color: var(--paper); }
.b-nav a[aria-current='page'] { color: var(--paper); }
.b-nav a[aria-current='page']::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  background: var(--signal);
}
.b-contact {
  color: var(--paper);
  font-size: 0.875rem;
  text-decoration: none;
  border: 1px solid var(--rule);
  padding: 0.5rem 0.9rem;
  border-radius: 0;
}
.b-contact:hover { border-color: var(--steel); }

.b-main { max-width: 1180px; margin: 0 auto; padding: clamp(3rem, 8vw, 6rem) var(--pad) 4rem; }

/* Eyebrow: mono label with the site's red rule */
.b-eyebrow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.6rem;
  margin: 0 0 1.5rem;
  color: var(--steel);
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}
.b-eyebrow::before { content: ''; width: 32px; height: 1px; background: var(--signal); }
.b-eyebrow a { color: var(--paper); text-decoration: none; }
.b-eyebrow a:hover { text-decoration: underline; text-decoration-color: var(--signal); text-underline-offset: 0.25em; }

/* Article header */
.b-article__header { max-width: 860px; margin: 0 0 clamp(2.5rem, 6vw, 4rem); }
.b-title {
  margin: 0;
  color: var(--paper);
  font-size: clamp(2.1rem, 5.2vw, 3.6rem);
  font-weight: 600;
  line-height: 1.06;
  letter-spacing: -0.035em;
  text-wrap: balance;
}
.b-dek {
  max-width: 62ch;
  margin: 1.5rem 0 0;
  color: var(--steel);
  font-size: clamp(1.1rem, 2vw, 1.3rem);
  line-height: 1.55;
  text-wrap: pretty;
}
.b-byline { margin: 1.75rem 0 0; color: var(--steel); font-family: var(--mono); font-size: 0.8rem; }
.b-byline a { color: var(--paper); text-decoration: none; border-bottom: 1px solid var(--signal); }

/* Layout: table of contents beside the text on wide screens */
.b-article__layout { display: grid; grid-template-columns: minmax(0, 1fr); gap: 2.5rem; }
@media (min-width: 1100px) {
  .b-article__layout { grid-template-columns: 208px minmax(0, var(--measure)); gap: 4rem; }
  .b-article__aside { position: sticky; top: 104px; align-self: start; max-height: calc(100vh - 128px); overflow: auto; }
}

.b-toc {
  border: 1px solid var(--rule);
  border-radius: 0;
  padding: 1rem 1.1rem;
  font-size: 0.875rem;
  line-height: 1.45;
}
@media (min-width: 1100px) { .b-toc { border: 0; padding: 0; border-left: 1px solid var(--rule); padding-left: 1.1rem; } }
.b-toc__label { margin: 0 0 0.75rem; color: var(--steel); font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.08em; text-transform: uppercase; }
.b-toc ol { margin: 0; padding: 0; list-style: none; counter-reset: toc; }
.b-toc li { counter-increment: toc; margin: 0 0 0.55rem; }
.b-toc a { display: flex; gap: 0.6rem; color: var(--steel); text-decoration: none; }
.b-toc a::before { content: counter(toc, decimal-leading-zero); color: #5c5c5c; font-family: var(--mono); font-size: 0.72rem; padding-top: 0.15em; }
.b-toc a:hover { color: var(--paper); }
.b-toc a:hover::before { color: var(--signal); }

/* Prose */
.b-prose { max-width: var(--measure); min-width: 0; }
.b-prose > :first-child { margin-top: 0; }
.b-prose p { margin: 0 0 1.35em; text-wrap: pretty; }
.b-prose > p:first-child { color: var(--paper); font-size: 1.2rem; line-height: 1.65; }
.b-prose strong { color: var(--paper); font-weight: 600; }
.b-prose em { color: var(--paper); }

.b-prose h2,
.b-prose h3 { position: relative; color: var(--paper); font-weight: 600; letter-spacing: -0.02em; text-wrap: balance; }
.b-prose { counter-reset: section; }
.b-prose h2 { counter-increment: section; margin: 3.2em 0 0.9em; padding-top: 1.4em; border-top: 1px solid var(--rule); font-size: clamp(1.45rem, 2.6vw, 1.8rem); line-height: 1.2; }
.b-prose h2::before { content: counter(section, decimal-leading-zero) ' /'; display: block; margin-bottom: 0.7rem; color: var(--steel); font-family: var(--mono); font-size: 0.75rem; font-weight: 400; letter-spacing: 0.06em; }
.b-prose h3 { margin: 2.2em 0 0.6em; font-size: 1.25rem; line-height: 1.3; }
.heading-anchor {
  position: absolute;
  left: -1.4em;
  width: 1.2em;
  color: var(--signal);
  font-weight: 400;
  text-decoration: none;
  opacity: 0;
  transition: opacity 120ms ease;
}
.b-prose h2:hover .heading-anchor,
.b-prose h3:hover .heading-anchor,
.heading-anchor:focus { opacity: 1; }
@media (max-width: 760px) { .heading-anchor { display: none; } }

.b-prose a {
  color: var(--paper);
  text-decoration: underline;
  text-decoration-color: var(--steel);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.22em;
}
.b-prose a:hover { text-decoration-color: var(--signal); text-decoration-thickness: 2px; }

.b-prose ul,
.b-prose ol { margin: 0 0 1.5em; padding-left: 1.3em; }
.b-prose li { margin: 0 0 0.55em; padding-left: 0.25em; }
.b-prose li::marker { color: var(--signal); font-family: var(--mono); font-size: 0.85em; }

.b-prose code {
  padding: 0.12em 0.38em;
  border: 1px solid var(--rule);
  border-radius: 0;
  background: var(--graphite);
  color: var(--paper);
  font-family: var(--mono);
  font-size: 0.85em;
}
.b-prose pre {
  margin: 0 0 1.6em;
  padding: 1.1rem 1.25rem;
  overflow-x: auto;
  border: 1px solid var(--rule);
  border-radius: 0;
  background: var(--graphite);
  font-size: 0.875rem;
  line-height: 1.6;
}
.b-prose pre code { padding: 0; border: 0; background: none; font-size: inherit; }

.b-prose blockquote {
  margin: 2em 0;
  padding: 0.2em 0 0.2em 1.4em;
  border-left: 2px solid var(--signal);
  color: var(--paper);
  font-size: 1.25rem;
  line-height: 1.5;
}
.b-prose blockquote p:last-child { margin-bottom: 0; }

.b-prose hr { margin: 3em 0; border: 0; border-top: 1px solid var(--rule); }

.b-prose figure { margin: 2.6em 0; }
.b-prose figure img { display: block; max-width: 100%; height: auto; border: 1px solid var(--rule); border-radius: 0; }
.b-prose figcaption { margin-top: 0.85rem; color: var(--steel); font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.02em; }

.table-wrap { margin: 0 0 1.6em; overflow-x: auto; border: 1px solid var(--rule); border-radius: 0; }
.b-prose table { width: 100%; border-collapse: collapse; font-size: 0.95rem; }
.b-prose th,
.b-prose td { padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--rule); text-align: left; vertical-align: top; }
.b-prose th { color: var(--steel); font-family: var(--mono); font-size: 0.72rem; font-weight: 500; letter-spacing: 0.06em; text-transform: uppercase; }
.b-prose tr:last-child td { border-bottom: 0; }

/* The system-design figure is wider than the text column on desktop. */
@media (min-width: 1100px) {
  .b-prose .b-figure-system { margin-right: -12rem; }
}

/* Article footer */
.b-article__footer {
  max-width: var(--measure);
  margin: 4.5rem 0 0;
  padding-top: 2rem;
  border-top: 1px solid var(--rule);
  color: var(--steel);
  font-size: 1rem;
}
@media (min-width: 1100px) { .b-article__footer { margin-left: calc(208px + 4rem); } }
.b-article__footer a { color: var(--paper); text-decoration-color: var(--steel); text-underline-offset: 0.2em; }
.b-article__footer a:hover { text-decoration-color: var(--signal); }
.b-back { font-family: var(--mono); font-size: 0.8rem; text-decoration: none !important; }
.b-back::before { content: '\2190\00a0'; color: var(--signal); }

/* Index */
.b-index__header { max-width: 860px; margin-bottom: clamp(3rem, 7vw, 5rem); }
.b-index__title {
  margin: 0;
  color: var(--paper);
  font-size: clamp(2.2rem, 5.5vw, 4rem);
  font-weight: 600;
  line-height: 1.04;
  letter-spacing: -0.04em;
  text-wrap: balance;
}
.b-list { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--rule); }
.b-list__item { border-bottom: 1px solid var(--rule); }
.b-list__link {
  display: grid;
  gap: 0.6rem;
  padding: clamp(1.5rem, 3vw, 2.25rem) 0;
  color: inherit;
  text-decoration: none;
}
@media (min-width: 860px) {
  .b-list__link { grid-template-columns: 220px minmax(0, 1fr); column-gap: 3rem; }
  .b-list__meta { grid-row: span 2; padding-top: 0.45rem; }
}
.b-list__meta { display: flex; gap: 0.5rem; color: var(--steel); font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.04em; text-transform: uppercase; }
.b-list__title { color: var(--paper); font-size: clamp(1.35rem, 2.6vw, 1.75rem); font-weight: 600; line-height: 1.2; letter-spacing: -0.02em; text-wrap: balance; }
.b-list__desc { max-width: 70ch; color: var(--steel); font-size: 1rem; line-height: 1.6; }
.b-list__link:hover .b-list__title { text-decoration: underline; text-decoration-color: var(--signal); text-decoration-thickness: 2px; text-underline-offset: 0.18em; }

/* Lead post on the index */
.b-lead { border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); }
.b-lead__label { margin: 1.5rem 0 0; color: var(--steel); font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; }
.b-lead__link { display: grid; gap: 0.9rem; padding: 1rem 0 clamp(2rem, 4vw, 3rem); color: inherit; text-decoration: none; }
.b-lead__meta { color: var(--steel); font-family: var(--mono); font-size: 0.75rem; letter-spacing: 0.04em; text-transform: uppercase; }
.b-lead__title { margin: 0; max-width: 24ch; color: var(--paper); font-size: clamp(1.75rem, 4vw, 2.5rem); font-weight: 600; line-height: 1.12; letter-spacing: -0.03em; text-wrap: balance; }
.b-lead__desc { max-width: 62ch; margin: 0; color: var(--text); font-size: clamp(1.05rem, 1.8vw, 1.25rem); line-height: 1.55; }
.b-lead__cta { color: var(--paper); font-family: var(--mono); font-size: 0.8rem; letter-spacing: 0.04em; text-transform: uppercase; }
.b-lead__cta::after { content: '\00a0\2192'; color: var(--signal); }
.b-lead__link:hover .b-lead__title { text-decoration: underline; text-decoration-color: var(--signal); text-decoration-thickness: 2px; text-underline-offset: 0.16em; }
.b-index__note { margin: 1.5rem 0 0; color: var(--steel); font-size: 0.95rem; }
.b-index__note a { color: var(--paper); text-decoration-color: var(--steel); text-underline-offset: 0.2em; }
.b-index__note a:hover { text-decoration-color: var(--signal); }
.b-section-label { margin: 3.5rem 0 1rem; color: var(--steel); font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; }

/* Footer */
.b-footer { border-top: 1px solid var(--rule); }
.b-footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.5rem 2rem;
  max-width: 1440px;
  margin: 0 auto;
  padding: 2.25rem var(--pad) 2.75rem;
  color: var(--steel);
  font-size: 0.875rem;
}
.b-footer__name { margin: 0; color: var(--paper); font-weight: 600; }
.b-footer__role { margin: 0; font-family: var(--mono); font-size: 0.75rem; }
.b-footer__links { display: flex; flex-wrap: wrap; gap: 0.5rem 1.25rem; margin-left: auto; }
.b-footer__links a { color: var(--steel); text-decoration: none; }
.b-footer__links a:hover { color: var(--paper); }

/* Small screens */
@media (max-width: 640px) {
  body { font-size: 1.0625rem; line-height: 1.68; }
  .b-header__inner { height: 64px; }
  .b-nav { gap: 1.1rem; }
  .b-contact { display: none; }
  .b-prose > p:first-child { font-size: 1.125rem; }
  .b-footer__links { margin-left: 0; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; scroll-behavior: auto !important; }
}

@media print {
  .b-header, .b-footer, .b-article__aside { display: none; }
  body { background: #fff; color: #111; }
  .b-title, .b-prose h2, .b-prose strong { color: #000; }
}

/* Timeline: from jalsy library timeline-002-horizontal-scroll-milestones, ported to vanilla.
   Default is a plain vertical list (no JS, phones, reduced motion); blog.js adds .tl--track. */
.tl { margin: 3em 0; }
.tl .tl__line,
.tl .tl__stem { display: none; }
.tl .tl__title { margin: 0; color: var(--paper); font-size: clamp(1.4rem, 3.6vw, 1.9rem); line-height: 1.1; letter-spacing: -0.03em; }
.tl .tl__title::before { content: none; }
.tl .tl__period { margin: 0.55rem 0 0; color: var(--steel); font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; }
.tl .tl__list { margin: 1.75rem 0 0 0.3rem; padding: 0 0 0 1.75rem; list-style: none; border-left: 1px solid #3a3a3a; }
.tl .tl__item { position: relative; margin: 0 0 1.6rem; padding: 0; }
.tl .tl__item:last-child { margin-bottom: 0; }
.tl .tl__dot { position: absolute; top: 0.5em; left: calc(-1.75rem - 0.5px); width: 9px; height: 9px; background: var(--paper); transform: translateX(-50%); }
.tl .tl__item:last-child .tl__dot { background: var(--signal); }
.tl .tl__mask { display: block; }
.tl .tl__date { display: block; color: var(--paper); font-family: var(--mono); font-size: 0.85rem; letter-spacing: 0.04em; text-transform: uppercase; }
.tl .tl__detail { display: block; margin-top: 0.3rem; color: var(--text); font-size: 1rem; line-height: 1.5; }

.tl--track {
  --tl-offset: 72px;
  --tl-step: clamp(9rem, 15vw, 16rem);
  --tl-h: min(max(22rem, 30vw), calc(100svh - var(--tl-offset) - 7rem));
  position: relative;
  margin: 4em 0;
}
.tl--track .tl__stage {
  position: sticky;
  top: var(--tl-offset);
  display: flex;
  align-items: center;
  height: calc(100svh - var(--tl-offset));
  overflow: hidden;
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  background: var(--ink);
}
.tl--track .tl__track { display: flex; flex-shrink: 0; width: max-content; height: var(--tl-h); padding: 0 6vw; will-change: transform; }
.tl--track .tl__body { position: relative; display: flex; height: 100%; }
.tl--track .tl__line { display: block; position: absolute; top: 50%; left: 0; right: 0; height: 1px; pointer-events: none; }
.tl__line-fill { position: absolute; inset: 0; background: #6a6a6a; transform-origin: 0 50%; transform: scaleX(0); }
.tl__line-start,
.tl__line-end { position: absolute; top: 50%; width: 11px; height: 11px; background: var(--paper); }
.tl__line-start { left: 0; transform: translate(-50%, -50%); }
.tl__line-end { right: 0; background: var(--signal); transform: translate(50%, -50%) scale(var(--tl-end, 0)); transition: transform 180ms ease; }

.tl--track .tl__head { display: grid; flex-shrink: 0; grid-template-rows: 1fr 1fr; width: calc(var(--tl-step) * 2); padding: 0 clamp(1.5rem, 3vw, 3rem) 0 2rem; }
.tl--track .tl__title { align-self: end; padding-bottom: 1.4rem; font-size: clamp(1.9rem, 3.2vw, 3.2rem); line-height: 0.98; letter-spacing: -0.04em; text-wrap: balance; }
.tl--track .tl__period { align-self: start; margin: 0; padding-top: 1.4rem; }

.tl--track .tl__list { display: grid; flex-shrink: 0; grid-template-rows: 1fr 1fr; height: 100%; margin: 0; padding: 0; border: 0; }
.tl--track .tl__item { display: flex; flex-direction: column; min-width: 0; margin: 0; }
.tl--track .tl__item:nth-child(odd) { grid-row: 1; justify-content: flex-start; }
.tl--track .tl__item:nth-child(even) { grid-row: 2; justify-content: flex-end; }
.tl--track .tl__stem { display: block; position: absolute; top: 0; bottom: 0; left: 0; width: 1px; background: #6a6a6a; transform: scaleY(clamp(0, calc(var(--p, 0) / 0.45), 1)); }
.tl--track .tl__item:nth-child(odd) .tl__stem { transform-origin: 50% 100%; }
.tl--track .tl__item:nth-child(even) .tl__stem { transform-origin: 50% 0; }
.tl--track .tl__dot { left: 0; width: 13px; height: 13px; }
.tl--track .tl__item:nth-child(odd) .tl__dot { top: 0; transform: translate(-50%, -50%) scale(clamp(0, calc((var(--p, 0) - 0.35) / 0.2), 1)); }
.tl--track .tl__item:nth-child(even) .tl__dot { top: auto; bottom: 0; transform: translate(-50%, 50%) scale(clamp(0, calc((var(--p, 0) - 0.35) / 0.2), 1)); }
.tl--track .tl__text { padding: 0 clamp(1rem, 2.2vw, 2.25rem); }
.tl--track .tl__item:nth-child(odd) .tl__text { margin-top: -0.75rem; }
.tl--track .tl__item:nth-child(even) .tl__text { margin-bottom: -0.35rem; }
.tl--track .tl__mask { overflow: hidden; }
.tl--track .tl__date {
  font-family: var(--sans);
  font-size: clamp(1.3rem, 2.1vw, 2.2rem);
  font-weight: 600;
  line-height: 1.12;
  letter-spacing: -0.03em;
  text-transform: none;
  transform: translateY(calc((1 - clamp(0, calc((var(--p, 0) - 0.3) / 0.5), 1)) * 110%));
}
.tl--track .tl__detail {
  max-width: 30ch;
  margin-top: 0.65rem;
  font-size: clamp(0.95rem, 1.1vw, 1.15rem);
  line-height: 1.38;
  transform: translateY(calc((1 - clamp(0, calc((var(--p, 0) - 0.38) / 0.5), 1)) * 110%));
}