/* Ethan Jiang — ethanjiang.com
   Built on the Broadsheet design tokens (Claude Design project ecc11379). */
@import url('https://fonts.googleapis.com/css2?family=Source+Serif+4:ital,wght@0,400;0,600;1,400&display=swap');

:root {
  --color-bg: #f3f2f2;
  --color-surface: #eae9e9;
  --color-text: #201e1d;
  --color-accent: #0088b0;
  --color-accent-2: #d6006c;
  --color-divider: color-mix(in srgb, #201e1d 16%, transparent);

  --color-neutral-100: #f8f4f4;
  --color-neutral-200: #eae7e7;
  --color-neutral-300: #d7d3d3;
  --color-neutral-400: #bab6b6;
  --color-neutral-500: #9b9797;
  --color-neutral-600: #7d7979;
  --color-neutral-700: #605d5d;
  --color-neutral-800: #444141;
  --color-neutral-900: #2d2b2b;

  --color-accent-100: #e9f8ff;
  --color-accent-200: #cbeeff;
  --color-accent-300: #99e0ff;
  --color-accent-600: #1186ac;
  --color-accent-700: #006786;
  --color-accent-800: #004961;

  --color-accent-2-100: #fff1f4;
  --color-accent-2-700: #aa0b56;
  --color-accent-2-800: #790e3d;

  --font-heading: "Source Serif 4", Georgia, serif;
  --font-body: "Source Serif 4", Georgia, serif;

  --space-1: 5px;
  --space-2: 10px;
  --space-3: 15px;
  --space-4: 20px;
  --space-6: 30px;
  --space-8: 40px;

  --radius-sm: 1px;
  --radius-md: 2px;
  --radius-lg: 4px;
}

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

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 { font-family: var(--font-heading); font-weight: 600; margin: 0; }
p { margin: 0; }
img { display: block; max-width: 100%; }
figure { margin: 0; }
a { color: var(--color-accent-700); text-decoration: none; }
a:hover { color: var(--color-accent-2-700); }
:focus { outline: none; }
:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
::selection { background: var(--color-accent-200); }

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

.skip-link {
  position: absolute; left: -9999px; top: 0; z-index: 99;
  background: var(--color-text); color: var(--color-bg);
  padding: 10px 16px;
}
.skip-link:focus { left: 0; }

/* — layout shell — */
.wrap { padding: 0 clamp(20px, 5vw, 64px); }

/* — header — */
.site-header {
  position: sticky; top: 0; z-index: 40;
  background: var(--color-bg);
}
.header-top {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 24px; flex-wrap: wrap; padding-top: 18px;
}
.brand {
  font-family: var(--font-heading); font-weight: 600;
  font-size: clamp(22px, 2.4vw, 30px); letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--color-text);
}
.brand:hover { color: var(--color-accent-700); }
.header-meta {
  font-size: 13px; letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--color-neutral-700); display: flex; gap: 18px; flex-wrap: wrap;
}
.rule-thick { height: 3px; background: var(--color-text); margin-top: 12px; }
.rule-thin { height: 1px; background: var(--color-text); }
.primary-nav {
  display: flex; gap: clamp(14px, 2.2vw, 30px); flex-wrap: wrap;
  padding: 9px 0; font-size: 15px; letter-spacing: 0.03em;
}
.primary-nav a {
  color: var(--color-neutral-600); border-bottom: 2px solid transparent;
  padding-bottom: 2px;
}
.primary-nav a:hover { color: var(--color-accent-2-700); }
.primary-nav a[aria-current="page"] {
  color: var(--color-text); border-bottom-color: var(--color-accent);
}

/* — main — */
main { padding: 0 clamp(20px, 5vw, 64px); }

/* — buttons — */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  cursor: pointer; text-decoration: none;
  font-family: var(--font-heading); font-weight: 600;
  font-size: 14px; line-height: 1.2; color: var(--color-text);
  background: transparent; border: 1px solid transparent;
  padding: var(--space-2) calc(var(--space-3) * 1.2);
  border-radius: var(--radius-md);
}
.btn-primary { background: var(--color-accent); color: var(--color-bg); }
.btn-primary:hover { background: var(--color-accent-600); color: var(--color-bg); }
.btn-secondary { border-color: var(--color-divider); color: var(--color-text); }
.btn-secondary:hover { background: color-mix(in srgb, var(--color-text) 7%, transparent); color: var(--color-text); }
.btn-ghost { color: var(--color-accent-700); padding-inline: var(--space-1); }
.btn-ghost:hover { background: color-mix(in srgb, var(--color-accent) 10%, transparent); color: var(--color-accent-700); }

/* — tags — */
.tag {
  display: inline-flex; align-items: center; font-size: 11px;
  letter-spacing: 0.02em; padding: 3px 10px; border-radius: 1.5px;
}
.tag-outline { border: 1px solid var(--color-accent); color: var(--color-accent-700); }

/* — hero (home) — */
.hero-stage { position: relative; height: 125vh; margin-top: clamp(24px, 5vh, 56px); }
.hero-sticky { position: sticky; top: 120px; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1fr); gap: clamp(16px, 3vw, 40px); }
.hero-kicker { margin: 0 0 10px; font-size: 13px; letter-spacing: 0.18em; text-transform: uppercase; color: var(--color-accent-700); max-width: 23ch; }
.hero-title { margin: 0; font-size: clamp(44px, 8.5vw, 104px); line-height: 0.95; letter-spacing: -0.02em; text-wrap: balance; max-width: 23ch; }
.hero-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: clamp(20px, 3vw, 48px); align-items: end; }
.hero-lede { margin: 0; font-size: clamp(17px, 1.5vw, 21px); line-height: 1.5; max-width: 46ch; color: var(--color-neutral-800); }
.hero-fold { justify-self: end; width: 100%; max-width: 640px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 4px; }
.hero-hint { margin: 2px 0 0; font-size: 13px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--color-neutral-600); }

/* — ledger + figure — */
.ledger-section { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: clamp(28px, 4vw, 64px); margin-top: clamp(48px, 8vh, 110px); align-items: start; }
.ledger-eyebrow { margin: 0 0 18px; font-size: 13px; letter-spacing: 0.18em; text-transform: uppercase; color: var(--color-accent-2-700); }
.ledger-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 2px; }
.ledger-row { display: grid; grid-template-columns: 56px minmax(0, 1fr); gap: 16px; align-items: baseline; padding: 9px 0; }
.ledger-n { font-family: var(--font-heading); font-size: 15px; color: var(--color-neutral-500); font-variant-numeric: tabular-nums; }
.ledger-text { font-family: var(--font-heading); font-size: clamp(19px, 2.1vw, 27px); line-height: 1.25; }
figcaption { margin-top: 10px; font-size: 14px; color: var(--color-neutral-700); max-width: 44ch; }

.pull-quote { margin-top: clamp(56px, 9vh, 120px); max-width: 60ch; padding-bottom: clamp(48px, 8vh, 100px); }
.pull-quote p { font-family: var(--font-heading); font-style: italic; font-size: clamp(24px, 3.4vw, 42px); line-height: 1.25; margin: 0; }

/* — interior page headers — */
.page-section { padding-top: clamp(36px, 6vh, 72px); padding-bottom: clamp(56px, 9vh, 110px); }
.page-eyebrow { margin: 0 0 10px; font-size: 13px; letter-spacing: 0.18em; text-transform: uppercase; color: var(--color-accent-700); }
.page-title { margin: 0 0 8px; font-size: clamp(38px, 6vw, 76px); line-height: 1; letter-spacing: -0.02em; }
.page-lede { margin: 0 0 clamp(32px, 6vh, 64px); max-width: 52ch; font-size: 18px; line-height: 1.6; color: var(--color-neutral-800); }
.page-note { margin: 0 0 clamp(28px, 5vh, 52px); font-size: 14px; color: var(--color-neutral-600); max-width: 52ch; }

/* — story timeline — */
.timeline-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: clamp(28px, 4vw, 72px); align-items: start; }
.timeline-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 0; }
.timeline-item-btn {
  all: unset; cursor: pointer; display: grid;
  grid-template-columns: minmax(90px, auto) minmax(0, 1fr);
  gap: clamp(16px, 2.5vw, 32px); align-items: baseline;
  padding: clamp(14px, 2vh, 22px) 0; width: 100%; box-sizing: border-box;
  border-top: 1px solid var(--color-divider);
}
.timeline-list li:last-child .timeline-item-btn { border-bottom: 1px solid var(--color-divider); }
.timeline-item-btn:hover { background: var(--color-neutral-100); }
.timeline-mark { font-family: var(--font-heading); font-size: clamp(17px, 1.7vw, 21px); letter-spacing: 0.1em; text-transform: uppercase; color: var(--color-neutral-600); }
.timeline-item-btn[aria-expanded="true"] .timeline-mark { color: var(--color-accent-2-700); }
.timeline-title { display: block; font-family: var(--font-heading); font-size: clamp(22px, 2.6vw, 34px); line-height: 1.2; color: var(--color-neutral-700); }
.timeline-item-btn[aria-expanded="true"] .timeline-title { color: var(--color-text); }
.timeline-teaser { display: block; margin-top: 6px; font-size: 16px; line-height: 1.6; color: var(--color-neutral-700); max-width: 44ch; }
.timeline-panel { position: sticky; top: 150px; }
.timeline-body { margin: 20px 0 0; font-size: clamp(17px, 1.6vw, 20px); line-height: 1.65; max-width: 44ch; }

/* — image placeholders — */
.img-frame { position: relative; display: block; }
.pending-badge {
  position: absolute; top: 10px; left: 10px;
  font-size: 11px; letter-spacing: 0.08em; text-transform: uppercase;
  background: var(--color-bg); color: var(--color-neutral-700);
  border: 1px solid var(--color-divider); padding: 3px 8px; border-radius: 1.5px;
}

/* — origami / works — */
.works-columns { columns: 3 320px; column-gap: clamp(18px, 2.5vw, 34px); }
.work-card { all: unset; cursor: zoom-in; display: block; width: 100%; break-inside: avoid; margin: 0 0 clamp(18px, 2.5vw, 34px); box-sizing: border-box; }
.work-card img { width: 100%; height: auto; display: block; background: var(--color-neutral-200); }
.work-meta { display: flex; justify-content: space-between; gap: 12px; align-items: baseline; margin-top: 9px; }
.work-title { font-family: var(--font-heading); font-size: 20px; line-height: 1.25; }
.work-form { font-size: 12px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--color-neutral-600); white-space: nowrap; }
.work-short { display: block; margin-top: 4px; font-size: 15px; line-height: 1.55; color: var(--color-neutral-700); }
.work-card.is-placeholder { border: 1px dashed var(--color-neutral-400); padding: 24px; cursor: default; }

/* — computational — */
.comp-intro-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: clamp(28px, 4vw, 64px); align-items: start; margin-bottom: clamp(44px, 7vh, 96px); }
.comp-block h3 { margin: 0 0 12px; font-size: clamp(22px, 2.3vw, 30px); line-height: 1.2; }
.comp-block p { margin: 0 0 14px; font-size: 17px; line-height: 1.65; max-width: 46ch; }
.comp-block p.muted { color: var(--color-neutral-700); }
.comp-block p.meta { font-size: 15px; line-height: 1.6; color: var(--color-neutral-600); margin: 0; }

.playground { margin-bottom: clamp(44px, 7vh, 96px); }
.playground h3 { margin: 0 0 8px; font-size: clamp(22px, 2.3vw, 30px); line-height: 1.2; }
.playground > p { margin: 0 0 24px; font-size: 17px; line-height: 1.65; max-width: 52ch; }
.playground-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: clamp(24px, 3vw, 48px); align-items: start; }
.playground-fold { min-width: 0; }
.playground-controls { display: grid; gap: 22px; max-width: 34ch; }
.range-field { display: grid; gap: 8px; font-size: 15px; }
.range-label-row { display: flex; justify-content: space-between; }
.range-value { font-variant-numeric: tabular-nums; color: var(--color-neutral-600); }
.range-field input[type="range"] { width: 100%; accent-color: var(--color-accent); }
.playground-note { margin: 0; font-size: 15px; line-height: 1.6; color: var(--color-neutral-700); }
.playground-note strong { font-variant-numeric: tabular-nums; color: var(--color-text); font-weight: 400; }
.playground-hint { margin: 0; font-size: 14px; line-height: 1.6; color: var(--color-neutral-600); }

.comp-grid-4 { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: clamp(24px, 3vw, 56px); }
.comp-grid-4 h3 { margin: 0 0 10px; font-size: clamp(20px, 2.1vw, 27px); line-height: 1.2; }
.comp-grid-4 p { margin: 0 0 10px; font-size: 16px; line-height: 1.65; }

/* — journal — */
.journal-post { border-top: 1px solid var(--color-divider); padding: clamp(20px, 3vh, 34px) 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: clamp(16px, 3vw, 48px); align-items: start; }
.journal-kicker { margin: 0 0 8px; font-size: 12px; letter-spacing: 0.16em; text-transform: uppercase; color: var(--color-accent-700); }
.journal-title { margin: 0; font-size: clamp(24px, 2.8vw, 36px); line-height: 1.15; max-width: 20ch; }
.journal-dek { margin: 0 0 12px; font-size: 17px; line-height: 1.65; max-width: 48ch; color: var(--color-neutral-800); }
.journal-meta { margin: 0; font-size: 14px; color: var(--color-neutral-600); }

/* — videos — */
.video-filters { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: clamp(24px, 4vh, 44px); }
.filter-btn { all: unset; cursor: pointer; font-size: 14px; letter-spacing: 0.06em; padding: 6px 14px; border: 1px solid var(--color-neutral-300); color: var(--color-neutral-700); background: transparent; border-radius: var(--radius-md); }
.filter-btn:hover { border-color: var(--color-accent); }
.filter-btn[aria-pressed="true"] { border-color: var(--color-text); color: var(--color-bg); background: var(--color-text); }
.video-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: clamp(20px, 2.5vw, 36px); }
.video-thumb { position: relative; background: var(--color-neutral-200); display: grid; place-items: center; border: 1px dashed var(--color-neutral-400); }
.video-thumb span { font-size: 13px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--color-neutral-600); }
.video-title { display: block; font-family: var(--font-heading); font-size: 19px; line-height: 1.3; margin-top: 10px; }
.video-cat { display: block; margin-top: 4px; font-size: 14px; color: var(--color-neutral-600); }

/* — gallery — */
.gallery-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: clamp(14px, 2vw, 26px); }
.gallery-item { all: unset; cursor: zoom-in; display: block; box-sizing: border-box; }
.gallery-item img { width: 100%; height: clamp(240px, 34vw, 420px); object-fit: cover; display: block; background: var(--color-neutral-200); }
.gallery-item span { display: block; margin-top: 8px; font-size: 14px; color: var(--color-neutral-700); }

/* — about — */
.about-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: clamp(28px, 4vw, 72px); align-items: start; }
.about-copy { max-width: 54ch; }
.about-copy p { margin: 0 0 18px; font-size: 17px; line-height: 1.7; }
.about-copy p.lead { margin: 0 0 20px; font-family: var(--font-heading); font-size: clamp(21px, 2.2vw, 28px); line-height: 1.45; }
.about-copy p.muted { color: var(--color-neutral-700); }
.about-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 28px; }

/* — lightbox — */
.lightbox {
  position: fixed; inset: 0; z-index: 80;
  background: color-mix(in srgb, #201e1d 88%, transparent);
  display: none; grid-template-rows: 1fr auto;
  padding: clamp(16px, 4vw, 56px); gap: 18px;
}
.lightbox.is-open { display: grid; }
.lightbox-image-wrap { min-height: 0; display: grid; }
.lightbox-image-wrap img { width: 100%; height: 100%; object-fit: contain; }
.lightbox-info { color: var(--color-bg); display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: clamp(14px, 3vw, 40px); align-items: start; }
.lightbox-title { margin: 0; font-family: var(--font-heading); font-size: clamp(22px, 2.4vw, 30px); line-height: 1.2; }
.lightbox-desc { margin: 6px 0 0; font-size: 15px; line-height: 1.6; opacity: 0.8; max-width: 44ch; }
.lightbox-fields { margin: 0; display: grid; grid-template-columns: auto 1fr; gap: 6px 18px; font-size: 14px; align-content: start; }
.lightbox-fields dt { opacity: 0.6; letter-spacing: 0.1em; text-transform: uppercase; font-size: 12px; padding-top: 2px; }
.lightbox-fields dd { margin: 0; opacity: 0.92; }
.lightbox-close { all: unset; cursor: pointer; justify-self: end; align-self: start; font-size: 14px; letter-spacing: 0.14em; text-transform: uppercase; border: 1px solid currentColor; padding: 8px 16px; border-radius: var(--radius-md); color: var(--color-bg); }
.lightbox-close:hover { color: var(--color-accent-300); }

/* — footer — */
.site-footer { margin-top: clamp(64px, 12vh, 150px); padding: 0 clamp(20px, 5vw, 64px) clamp(40px, 7vh, 80px); }
.footer-rule { height: 1px; background: var(--color-text); margin-bottom: 20px; }
.footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 24px; align-items: baseline; }
.footer-brand { margin: 0; font-family: var(--font-heading); font-size: 18px; letter-spacing: 0.14em; text-transform: uppercase; }
.footer-tag { margin: 0; font-size: 14px; color: var(--color-neutral-700); max-width: 36ch; }
.footer-link { margin: 0; font-size: 14px; }