/* PipelineClear — design tokens */
:root {
  --bg: #F5F6F2;
  --surface: #FFFFFF;
  --ink: #14201C;
  --ink-muted: #4B5750;
  --accent: #2E7D5B;
  --accent-soft: #E4EFE9;
  --flag: #C77D2E;
  --line: #D8DAD3;
  --max-w: 760px;
}

* { box-sizing: border-box; }

img { max-width: 100%; height: auto; }

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; border-bottom: 1px solid transparent; }
a:hover, a:focus-visible { border-bottom-color: var(--accent); }
a:focus-visible, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

h1, h2, h3 {
  font-family: 'Space Grotesk', 'IBM Plex Sans', sans-serif;
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--ink);
}

h2[id] { scroll-margin-top: 110px; }

code, .mono {
  font-family: 'IBM Plex Mono', ui-monospace, Menlo, monospace;
}

/* ---------- Header ---------- */
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 960px;
  margin: 0 auto;
  padding: 16px 24px;
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 600;
  font-size: 1.15rem;
  color: var(--ink);
  border-bottom: none;
}

.brand .dot { color: var(--accent); }

.site-nav { display: flex; gap: 20px; font-size: 0.95rem; }
.site-nav a { color: var(--ink-muted); border-bottom: none; padding: 10px 4px; }
.site-nav a:hover { color: var(--accent); }

/* ---------- Hero ---------- */
.hero {
  max-width: 960px;
  margin: 0 auto;
  padding: 64px 24px 40px;
}

.hero h1 {
  font-size: clamp(2.1rem, 4vw, 3rem);
  max-width: 14ch;
  margin: 0 0 20px;
}

.hero p.byline {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.88rem;
  color: var(--accent);
  margin: 0 0 18px;
}

.hero p.lede {
  max-width: 56ch;
  font-size: 1.15rem;
  color: var(--ink-muted);
  margin: 0 0 40px;
}

/* Pipeline diagram */
.pipeline {
  display: flex;
  align-items: stretch;
  gap: 0;
  margin: 40px 0 8px;
  overflow-x: auto;
}

.stage {
  flex: 1 1 0;
  min-width: 130px;
  position: relative;
  padding: 18px 16px 16px;
  background: var(--surface);
  border: 1px solid var(--line);
}

.stage + .stage { border-left: none; }

.stage .n {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.72rem;
  color: var(--ink-muted);
  display: block;
  margin-bottom: 10px;
}

.stage .label {
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 600;
  font-size: 0.98rem;
}

.stage.clear { background: var(--accent-soft); }
.stage.clear .label { color: var(--accent); }
.stage.clear .label::after { content: ' ✓'; }

.pipeline-caption {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.8rem;
  color: var(--ink-muted);
  margin: 0 0 8px;
}

/* ---------- Sections ---------- */
.section {
  max-width: 960px;
  margin: 0 auto;
  padding: 56px 24px;
  border-top: 1px solid var(--line);
}

.section h2 {
  font-size: 1.5rem;
  margin: 0 0 24px;
}

.section .intro {
  max-width: var(--max-w);
  color: var(--ink-muted);
  margin: -8px 0 32px;
}

/* Post preview list */
.post-list { list-style: none; margin: 0; padding: 0; }

.post-item {
  padding: 24px 0;
  border-top: 1px solid var(--line);
}
.post-item:first-child { border-top: none; padding-top: 0; }

.post-item .date {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.82rem;
  color: var(--ink-muted);
}

.post-item h3 { margin: 6px 0 8px; font-size: 1.25rem; }
.post-item h3 a { color: var(--ink); border-bottom: none; }
.post-item h3 a:hover { color: var(--accent); }

.post-item p { max-width: var(--max-w); color: var(--ink-muted); margin: 0; }

/* Vision / about grid */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}

@media (max-width: 640px) {
  .about-grid { grid-template-columns: 1fr; }
  .pipeline { flex-direction: column; }
  .stage + .stage { border-left: 1px solid var(--line); border-top: none; }
  .site-header { flex-wrap: wrap; row-gap: 14px; }
  .site-nav { gap: 20px; flex-wrap: wrap; row-gap: 8px; font-size: 0.9rem; }
  .bio { flex-direction: column-reverse; gap: 20px; }
  .bio-photo { width: 160px; }
}

.about-grid h3 { font-size: 1.05rem; margin: 0 0 10px; }
.about-grid p { color: var(--ink-muted); margin: 0; font-size: 0.98rem; }

/* CTA */
.cta-box {
  background: var(--ink);
  color: var(--bg);
  padding: 40px;
  margin-top: 8px;
}
.cta-box h2 { color: var(--bg); }
.cta-box p { color: #C7CFC9; max-width: var(--max-w); }
.cta-box a { color: #9AD9BE; }
.cta-box a:hover { border-bottom-color: #9AD9BE; }

/* ---------- Article page ---------- */
.article {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 48px 24px 80px;
}

.article .back { font-family: 'IBM Plex Mono', monospace; font-size: 0.85rem; }
.article .meta {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.82rem;
  color: var(--ink-muted);
  margin: 24px 0 14px;
}

.tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin: 0 0 28px;
}

.tag {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.76rem;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid var(--line);
  padding: 8px 12px;
  border-radius: 3px;
}

.post-item .tags {
  margin: 10px 0 10px;
}

a.tag:hover, a.tag:focus-visible { border-bottom-color: var(--accent); }

/* ---------- Table of contents ---------- */
.toc {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 18px 22px;
  margin: 0 0 36px;
  background: var(--surface);
}

.toc-title {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-muted);
  margin: 0 0 10px;
}

.toc ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 7px;
}

.toc a { font-size: 0.95rem; }

/* ---------- Share links ---------- */
.share {
  display: flex;
  align-items: center;
  gap: 2px 8px;
  flex-wrap: wrap;
  margin: 40px 0 0;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  font-size: 0.9rem;
  color: var(--ink-muted);
}

.share span { margin-right: 6px; }

.share a {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.85rem;
  padding: 10px 8px;
}

/* ---------- Reading progress bar ---------- */
#progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: var(--accent);
  z-index: 100;
}

/* ---------- Topics page ---------- */
.topic-group { margin: 0 0 36px; }
.topic-group h2 { margin-bottom: 12px; }
.topic-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.topic-list .date {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.8rem;
  color: var(--ink-muted);
  margin-right: 10px;
}

/* ---------- 404 ---------- */
.not-found { text-align: left; }
.not-found .lede { color: var(--ink-muted); }

/* ---------- Byline ---------- */
.byline {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 18px 22px;
  margin: 32px 0 0;
  background: var(--surface);
}

.byline-name {
  font-weight: 500;
  margin: 0 0 6px;
}

.byline-bio {
  margin: 0;
  color: var(--ink-muted);
  font-size: 0.95rem;
}

/* ---------- Keep reading ---------- */
.keep-reading { margin: 32px 0 0; }

/* ---------- Copy link ---------- */
.copy-link {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.85rem;
  color: var(--accent);
  background: none;
  border: none;
  border-bottom: 1px solid transparent;
  padding: 10px 8px;
  cursor: pointer;
}

.copy-link:hover { border-bottom-color: var(--accent); }

.visit-counter {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.8rem;
  color: var(--ink-muted);
}

.visit-counter #gcvc {
  color: var(--accent);
  font-weight: 500;
}

.article h1 { font-size: clamp(1.8rem, 3.5vw, 2.4rem); margin: 0 0 8px; }
.article h2 { font-size: 1.35rem; margin: 40px 0 14px; }
.article p { margin: 0 0 20px; }
.article ul, .article ol { margin: 0 0 20px; padding-left: 22px; }
.article li { margin-bottom: 8px; }

.article pre {
  background: var(--ink);
  color: #E8ECE9;
  padding: 18px 20px;
  overflow-x: auto;
  font-size: 0.88rem;
  line-height: 1.5;
  margin: 0 0 24px;
}

.article .callout {
  border-left: 3px solid var(--flag);
  background: #FBF3EA;
  padding: 14px 18px;
  font-size: 0.92rem;
  color: #6B4B22;
  margin: 0 0 28px;
}

.article hr { border: none; border-top: 1px solid var(--line); margin: 40px 0; }

/* Series navigation */
.series-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  margin: 40px 0 0;
  padding: 18px 20px;
  background: var(--surface);
  border: 1px solid var(--line);
}

.series-nav a {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.85rem;
  color: var(--ink);
  border-bottom: none;
  max-width: 48%;
  line-height: 1.5;
}

.series-nav a:hover { color: var(--accent); }
.series-nav .next { margin-left: auto; text-align: right; }

@media (max-width: 640px) {
  .series-nav a { max-width: 100%; }
  .series-nav .next { margin-left: 0; text-align: left; }
}

.series-link {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.82rem;
  color: var(--ink-muted);
  text-align: center;
  margin: 16px 0 0;
}

/* Series page */
.series-list { list-style: none; margin: 0 0 32px; padding: 0; counter-reset: part; }

.series-list li {
  counter-increment: part;
  position: relative;
  padding: 24px 0 24px 56px;
  border-top: 1px solid var(--line);
}

.series-list li::before {
  content: counter(part, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 28px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.85rem;
  color: var(--accent);
}

.series-list h3 { margin: 6px 0 8px; font-size: 1.2rem; }
.series-list h3 a { color: var(--ink); border-bottom: none; }
.series-list h3 a:hover { color: var(--accent); }
.series-list p { color: var(--ink-muted); margin: 0; }
.series-list .date {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.8rem;
  color: var(--ink-muted);
}

.series-promo {
  max-width: var(--max-w);
  color: var(--ink-muted);
  margin: 24px 0 0;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

/* About page */
.bio {
  display: flex;
  gap: 40px;
  align-items: stretch;
  margin: 32px 0 8px;
}
.bio-text { flex: 1; min-width: 0; }
.bio-photo {
  width: 200px;
  height: auto;
  border-radius: 12px;
  border: 1px solid var(--line);
  flex-shrink: 0;
  object-fit: cover;
}
.bio-text h2 { margin-top: 0; }
.bio-text .role {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.9rem;
  color: var(--ink-muted);
  margin: -8px 0 20px;
}
.edu-card {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 20px 24px;
  margin: 0 0 8px;
}
.edu-card p { margin: 0 0 6px; }
.edu-card p:last-child { margin-bottom: 0; }
.edu-degree { font-weight: 600; font-size: 1.05rem; }
.edu-school { color: var(--ink-muted); }
.edu-year {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.85rem;
  color: var(--ink-muted);
}

/* ---------- Footer ---------- */
.site-footer {
  max-width: 960px;
  margin: 0 auto;
  padding: 32px 24px 56px;
  font-size: 0.85rem;
  color: var(--ink-muted);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}