/* Layout: a full-screen Fourier "hello" opens the page; below it, one centered reading column (1080px)
   that alternates full-width sections and two-column splits. Mono labels act like figure captions. */
:root {
  --bg: #EDF0EE;
  --surface: #F6F8F7;
  --fg: #121615;
  --muted: #5A6460;
  --line: #D2D8D5;
  --accent: #2E47E0;
  --hot: #E2711D;
  --ring: rgba(46, 40, 84, 0.16);
  --arm: rgba(36, 32, 60, 0.75);
  --glow: 0;
  --display: "Big Shoulders Display", "Arial Narrow", "Helvetica Neue", sans-serif;
  --body: "Geist", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "Cascadia Mono", Consolas, monospace;
  --top-h: 60px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0B0E0F; --surface: #12171A; --fg: #E5EBE8; --muted: #8C9793; --line: #232B2E;
    --accent: #8FA1FF; --hot: #FFB05C;
    --ring: rgba(214, 208, 255, 0.15); --arm: rgba(236, 233, 255, 0.7); --glow: 1; color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0B0E0F; --surface: #12171A; --fg: #E5EBE8; --muted: #8C9793; --line: #232B2E;
  --accent: #8FA1FF; --hot: #FFB05C;
  --ring: rgba(214, 208, 255, 0.15); --arm: rgba(236, 233, 255, 0.7); --glow: 1; color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--top-h) + env(safe-area-inset-top, 0px) + 12px); }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font-family: var(--body); font-size: 16px; line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
body::before { content: ""; position: fixed; inset: 0 0 auto; height: env(safe-area-inset-top, 0px); z-index: 30; background: var(--bg); }
img { max-width: 100%; }
[hidden] { display: none !important; }
a { color: inherit; }
button { font: inherit; color: inherit; cursor: pointer; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
.gutter { padding-left: max(20px, env(safe-area-inset-left, 0px)); padding-right: max(20px, env(safe-area-inset-right, 0px)); }
.wrap { max-width: 1080px; margin: 0 auto; }
.muted { color: var(--muted); }
.eyebrow { font-family: var(--mono); font-size: 12px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); }

/* ---------- top bar ---------- */
.topbar {
  position: fixed; top: env(safe-area-inset-top, 0px); left: 0; right: 0; z-index: 20; height: var(--top-h);
  display: flex; align-items: center; gap: 20px;
  background: color-mix(in srgb, var(--bg) 78%, transparent); backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent; transition: border-color .2s;
}
.topbar.scrolled { border-bottom-color: var(--line); }
.mark { font-family: var(--display); font-weight: 900; font-size: 26px; letter-spacing: 0.02em; text-decoration: none; }
.nav { display: flex; gap: 22px; margin-left: auto; font-size: 14px; }
.nav a { text-decoration: none; color: var(--muted); }
.nav a:hover, .nav a.on { color: var(--fg); }
.pill {
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.04em; text-transform: uppercase; text-decoration: none;
  display: inline-flex; align-items: center; background: color-mix(in srgb, var(--bg) 72%, transparent);
  border: 1px solid var(--line); border-radius: 999px; padding: 7px 13px; white-space: nowrap;
}
.pill:hover { border-color: var(--fg); }
.pill.primary { background: var(--fg); color: var(--bg); border-color: var(--fg); }

/* ---------- hero ---------- */
.hero { position: relative; height: 100svh; min-height: 560px; overflow: hidden; }
.hero canvas { position: absolute; inset: 0; width: 100%; height: 100%; display: block; touch-action: pan-y; }
.hero-bottom {
  position: absolute; left: 0; right: 0; bottom: 0; display: flex; align-items: flex-end; justify-content: space-between;
  flex-wrap: wrap; gap: 16px 24px; padding-bottom: calc(24px + env(safe-area-inset-bottom, 0px)); pointer-events: none;
}
.hero-bottom > * { pointer-events: auto; }
.intro { display: grid; gap: 10px; max-width: 58ch; min-width: 0; }
.intro h1 { margin: 0; font-size: clamp(21px, 2.6vw, 30px); line-height: 1.22; font-weight: 600; letter-spacing: -0.015em; text-wrap: balance; }
.lede { margin: 0; color: var(--fg); opacity: 0.82; font-size: 15px; max-width: 58ch; }
.lede.small { font-family: var(--mono); font-size: 12px; opacity: 1; color: var(--muted); }
.links { display: flex; flex-wrap: wrap; gap: 6px 18px; font-size: 15px; }
.links a { text-decoration: none; border-bottom: 1px solid var(--line); }
.links a:hover { border-color: var(--accent); }

/* hero controls */
.hero.drawing canvas { cursor: crosshair; touch-action: none; }
.fhint { position: absolute; left: 50%; top: 42%; transform: translate(-50%, -50%); font-size: clamp(20px, 3vw, 28px); font-style: italic; color: var(--muted); pointer-events: none; text-align: center; }
.hero-ctl { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 8px; min-width: 0; }
.check { gap: 8px; cursor: pointer; }
.check input { margin: 0; accent-color: var(--accent); }

/* ---------- sections ---------- */
.section { padding-block: clamp(64px, 9vw, 112px) 0; }
.sec-head { display: grid; gap: 8px; margin-bottom: 32px; max-width: 66ch; }
.sec-head h2 { margin: 0; font-family: var(--display); font-weight: 900; font-size: clamp(34px, 5vw, 56px); line-height: 0.95; letter-spacing: 0.005em; text-transform: uppercase; text-wrap: balance; }
.sec-head p { margin: 4px 0 0; color: var(--muted); }
.two { display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr); gap: 56px; }
.side .sec-head { margin-bottom: 16px; }
.side .sec-head h2 { font-size: clamp(26px, 3vw, 34px); }
.side .sec-head + * { margin-bottom: 40px; }

/* the stack */
.layers { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--line); }
.layer { display: grid; grid-template-columns: 180px minmax(0, 1fr) auto; gap: 8px 24px; align-items: baseline; padding: 18px 0; border-bottom: 1px solid var(--line); }
.layer-k { font-family: var(--display); font-weight: 800; font-size: 24px; text-transform: uppercase; letter-spacing: 0.01em; }
.layer-what { color: var(--muted); }
.layer-refs { display: flex; gap: 8px; flex-wrap: wrap; justify-content: flex-end; }
.layer-refs a { font-family: var(--mono); font-size: 12px; text-decoration: none; border: 1px solid var(--line); border-radius: 999px; padding: 3px 10px; }
.layer-refs a:hover { border-color: var(--accent); color: var(--accent); }

/* case studies */
.case { border-top: 1px solid var(--line); padding-block: 32px 40px; }
.case h3 { margin: 6px 0 4px; font-family: var(--display); font-weight: 900; font-size: clamp(32px, 4.4vw, 52px); line-height: 0.95; text-transform: uppercase; }
.case.small h3 { font-size: clamp(24px, 2.6vw, 30px); line-height: 1.05; }
.case-sub { margin: 0 0 24px; color: var(--muted); font-size: 17px; max-width: 60ch; }
.case-meta { display: flex; flex-wrap: wrap; gap: 6px 14px; font-family: var(--mono); font-size: 12px; color: var(--muted); }
.tag { color: var(--bg); background: var(--accent); border-radius: 4px; padding: 0 6px; }
.case-grid { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr); gap: 40px; align-items: start; }
.case-text h4 { margin: 18px 0 4px; font-family: var(--mono); font-size: 12px; font-weight: 500; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); }
.case-text h4:first-child { margin-top: 0; }
.case-text p { margin: 0; max-width: 64ch; }
.case-fig { margin: 0; display: grid; gap: 8px; }
.case-fig figcaption { font-family: var(--mono); font-size: 11px; color: var(--muted); }
.stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; margin: 28px 0 0; }
.stats div { border-left: 2px solid var(--accent); padding-left: 12px; }
.stats dt { font-family: var(--mono); font-size: 11px; letter-spacing: 0.06em; text-transform: uppercase; color: var(--muted); }
.stats dd { margin: 2px 0 0; font-family: var(--display); font-weight: 800; font-size: clamp(26px, 3vw, 36px); line-height: 1; font-variant-numeric: tabular-nums; }
.stats.compact { grid-template-columns: repeat(3, minmax(0, 1fr)); margin-top: 18px; }
.stats.compact dd { font-size: 24px; }
.fine { margin: 10px 0 0; font-family: var(--mono); font-size: 11px; color: var(--muted); }
.case-row { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 0 32px; }
.case.small ul { margin: 12px 0 0; padding-left: 18px; display: grid; gap: 6px; }
.aside { margin: 16px 0 0; padding: 12px 14px; background: var(--surface); border-radius: 8px; font-size: 14px; color: var(--muted); }

/* DeepMSI pipeline diagram */
.pipe { width: 100%; height: auto; max-width: 420px; }
.pipe rect { fill: var(--surface); stroke: var(--line); }
.pipe rect.hot { fill: color-mix(in srgb, var(--accent) 16%, var(--surface)); stroke: var(--accent); }
.pipe text { font-family: var(--mono); font-size: 12px; fill: var(--fg); }
.pipe text.r { text-anchor: end; fill: var(--muted); }
.pipe path { stroke: var(--muted); stroke-width: 1.2; fill: none; }

/* ADMM bars */
.bars { display: grid; gap: 10px; }
.bar-row { display: grid; grid-template-columns: 92px minmax(0, 1fr) 84px; gap: 10px; align-items: center; font-family: var(--mono); font-size: 12px; }
.bar-k { color: var(--muted); }
.bar { height: 14px; background: var(--surface); border-radius: 3px; overflow: hidden; }
.bar i { display: block; height: 100%; width: var(--w); background: var(--muted); opacity: 0.55; }
.bar i.hot { background: var(--accent); opacity: 1; min-width: 3px; }
.bar-v { text-align: right; font-variant-numeric: tabular-nums; }

/* experience */
.timeline { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--line); }
.timeline li { display: grid; grid-template-columns: 140px minmax(0, 1fr); gap: 16px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.when { font-family: var(--mono); font-size: 12px; color: var(--muted); padding-top: 3px; font-variant-numeric: tabular-nums; }
.where { font-family: var(--mono); font-size: 11px; color: var(--muted); margin-left: 6px; }
.timeline p { margin: 4px 0 0; color: var(--muted); font-size: 15px; }
.plain { list-style: none; margin: 0; padding: 0; display: grid; gap: 16px; font-size: 15px; }
.tools { margin: 0; color: var(--muted); font-size: 15px; }

/* about */
.prose { margin: 0 0 14px; max-width: 62ch; font-size: 17px; }
.tags { list-style: none; margin: 0 0 12px; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.tags li { border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px; font-size: 14px; }

/* contact */
.contact { padding-bottom: clamp(64px, 9vw, 112px); }
.contact h2 { margin: 10px 0 8px; font-family: var(--display); font-weight: 900; font-size: clamp(36px, 6vw, 72px); line-height: 0.95; text-transform: uppercase; max-width: 18ch; text-wrap: balance; }
.contact-row { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-top: 24px; }
.email { font-family: var(--mono); font-size: clamp(16px, 2vw, 20px); user-select: all; margin-right: 6px; }

.foot { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 8px 24px; padding-block: 24px calc(24px + env(safe-area-inset-bottom, 0px)); border-top: 1px solid var(--line); font-family: var(--mono); font-size: 12px; color: var(--muted); }

/* 404 */
.lost { min-height: 100svh; display: grid; align-items: center; padding-block: 48px; }
.lost h1 { margin: 10px 0 8px; font-family: var(--display); font-weight: 900; font-size: clamp(40px, 7vw, 84px); line-height: 0.95; text-transform: uppercase; max-width: 16ch; text-wrap: balance; }
.lost .pill { margin-top: 16px; }

/* ---------- narrow screens ---------- */
@media (max-width: 860px) {
  .two, .case-grid { grid-template-columns: minmax(0, 1fr); gap: 32px; }
  .case-row { grid-template-columns: minmax(0, 1fr); }
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); row-gap: 18px; }
  .layer { grid-template-columns: minmax(0, 1fr); }
  .layer-refs { justify-content: flex-start; }
}
@media (max-width: 640px) {
  .nav { display: none; }
  #theme { margin-left: auto; }
  .hero-bottom { flex-direction: column; align-items: stretch; }
  .hero-ctl { justify-content: flex-start; }
  .timeline li { grid-template-columns: minmax(0, 1fr); gap: 4px; }
  .stats.compact { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}