/* Design tokens. One accent (burnt orange) on cool greys.
   Theme: js/theme.js sets <html data-theme="light|dark"> from the visitor's saved choice or system setting.
   Without JavaScript, the prefers-color-scheme fallback below still gives dark mode. */
:root {
  --bg: #F3F4F6;
  --surface: #FBFBFC;
  --ink: #16191E;
  --muted: #4B5260;
  --line: #D8DCE2;
  --accent: #B4440F;
  --accent-soft: #F5E5DA;
  --on-accent: #FDFBFA;
  --todo-bg: #FFF1BF;
  --todo-ink: #5A4300;
  --radius: 12px;
  --font: "Geist", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "Geist Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;
  color-scheme: light;
}

/* Dark tokens, applied by an explicit choice or, with no choice saved, by the system setting. */
:root[data-theme="dark"] {
  --bg: #121418;
  --surface: #1A1D22;
  --ink: #ECEEF1;
  --muted: #A3AAB6;
  --line: #2E333B;
  --accent: #F08A4B;
  --accent-soft: #2B1E16;
  --on-accent: #1A0E06;
  color-scheme: dark;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --bg: #121418;
    --surface: #1A1D22;
    --ink: #ECEEF1;
    --muted: #A3AAB6;
    --line: #2E333B;
    --accent: #F08A4B;
    --accent-soft: #2B1E16;
    --on-accent: #1A0E06;
    color-scheme: dark;
  }
}

/* Gentle cross-fade when the visitor switches theme. */
@media (prefers-reduced-motion: no-preference) {
  body, .site-header, .band, .node, .chip, .btn { transition: background-color .2s ease, color .2s ease, border-color .2s ease; }
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body { margin: 0; background: var(--bg); color: var(--ink); font-family: var(--font); line-height: 1.55; }
img { max-width: 100%; display: block; }
a { color: var(--accent); }
a:hover { color: var(--ink); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
h1, h2, h3, h4, p { margin: 0; }

.container { max-width: 1180px; margin: 0 auto; padding-inline: 24px; }
.section { padding-block: 72px; }
.section-tight { padding-block: 48px; }
.band { border-top: 1px solid var(--line); }
.band-surface { background: var(--surface); }
.muted { color: var(--muted); }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.todo { font-family: var(--mono); font-size: .85em; background: var(--todo-bg); color: var(--todo-ink); padding: 2px 6px; border-radius: 4px; }

/* Buttons: interactive controls are pills; containers use --radius. */
.btn { display: inline-block; text-decoration: none; font-weight: 500; padding: 12px 22px; border-radius: 999px; white-space: nowrap; border: 1px solid transparent; }
.btn-accent { background: var(--accent); color: var(--on-accent); }
.btn-accent:hover { color: var(--on-accent); filter: brightness(1.08); }
.btn-ink { background: var(--ink); color: var(--bg); }
.btn-ink:hover { color: var(--bg); }
.btn-outline { border-color: var(--ink); color: var(--ink); }
@media (prefers-reduced-motion: no-preference) {
  .press { transition: transform .18s cubic-bezier(.16, 1, .3, 1); }
  .press:active { transform: translateY(1px) scale(.98); }
  .featured { transition: transform .25s cubic-bezier(.16, 1, .3, 1); }
}

/* Header */
.site-header { border-bottom: 1px solid var(--line); }
.nav { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px; padding-block: 14px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); font-weight: 600; }
.monogram { display: inline-grid; place-items: center; width: 36px; height: 36px; border-radius: 999px; background: var(--ink); color: var(--bg); font-size: 14px; letter-spacing: -.02em; }
.nav-links { display: flex; flex-wrap: wrap; align-items: center; gap: 2px; }
.nav-links a:not(.btn) { color: var(--ink); text-decoration: none; padding: 12px; font-size: 15px; }
.nav-links .btn { margin-left: 8px; font-size: 15px; padding: 11px 18px; }
.theme-toggle { display: inline-grid; place-items: center; width: 44px; height: 44px; margin-left: 4px; padding: 0; border: 1px solid var(--line); border-radius: 999px; background: transparent; color: var(--ink); cursor: pointer; }
.theme-toggle[hidden] { display: none; }
.theme-toggle:hover { border-color: var(--ink); }
.theme-toggle .icon-sun { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
:root[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

/* Hero */
.hero { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 340px), 1fr)); gap: 56px; align-items: center; padding-block: 72px 64px; }
.hero-copy { max-width: 680px; }
.hero-intro { font-size: 18px; color: var(--muted); margin-bottom: 18px; }
.hero h1 { font-size: clamp(36px, 5vw, 50px); line-height: 1.08; letter-spacing: -.03em; font-weight: 600; text-wrap: balance; }
.hero h1 em { color: var(--accent); }
.hero-summary { margin-top: 22px; font-size: 19px; color: var(--muted); max-width: 52ch; text-wrap: pretty; }
.actions { margin-top: 32px; display: flex; flex-wrap: wrap; gap: 12px; }
.hero-photo { justify-self: end; width: 100%; max-width: 420px; height: auto; aspect-ratio: 4 / 5; object-fit: cover; object-position: 50% 45%; border-radius: var(--radius); border: 1px solid var(--line); background: var(--accent-soft); }

/* Facts and stats */
.facts { margin: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px 32px; font-size: 15px; }
.facts dt { color: var(--muted); }
.facts dd { margin: 4px 0 0; font-weight: 500; }
.stats { margin-top: 40px; display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 28px; }
.stat { border-left: 3px solid var(--line); padding-left: 16px; }
.stat-accent { border-left-color: var(--accent); }
.stat-value { font-size: 40px; font-weight: 600; letter-spacing: -.03em; line-height: 1.1; }
.stat-label { margin-top: 6px; font-size: 15px; color: var(--muted); }

/* Section headings */
.section-title { font-size: clamp(28px, 4vw, 36px); font-weight: 600; letter-spacing: -.02em; }
.section-lead { margin-top: 10px; font-size: 17px; color: var(--muted); max-width: 60ch; }
.subsection-title { font-size: 22px; font-weight: 600; }
#work .subsection-title { margin-top: 80px; }
.kicker { font-size: 15px; color: var(--muted); }

/* Featured work */
.featured { margin-top: 48px; display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 380px), 1fr)); gap: 36px; align-items: center; }
.featured-copy h3 { margin-top: 8px; font-size: 28px; font-weight: 600; letter-spacing: -.02em; line-height: 1.2; }
.featured-copy > p:not(.kicker) { margin-top: 14px; font-size: 16px; color: var(--muted); max-width: 52ch; }
.featured-copy .btn { margin-top: 22px; }
@media (min-width: 820px) { .featured-reverse .diagram { order: 2; } }

/* Diagrams, built from HTML so they scale and read in both themes */
.diagram { margin: 0; aspect-ratio: 16 / 10; border-radius: var(--radius); background: var(--bg); border: 1px solid var(--line); padding: 28px; display: flex; flex-direction: column; justify-content: center; gap: 18px; min-width: 0; }
.diagram-soft { background: var(--accent-soft); }
.diagram-label { font-size: 13px; color: var(--muted); margin-bottom: 8px; }
.diagram-label-accent { color: var(--accent); font-weight: 500; }
.flow { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.flow-center { justify-content: center; }
.node { flex: 1 1 100px; background: var(--surface); border: 1px solid var(--ink); border-radius: var(--radius); padding: 12px 14px; font-size: 14px; font-weight: 500; }
.node small { display: block; font-weight: 400; color: var(--muted); font-size: 13px; }
.node-dashed { border-style: dashed; border-color: var(--muted); }
.node-accent { border: 2px solid var(--accent); background: var(--accent-soft); }
.diagram-soft .node-accent { background: var(--surface); }
.node-wide { flex-grow: 1.4; }
.node-half { flex: 0 1 46%; min-width: 160px; }
.arrow { color: var(--muted); font-size: 18px; }
.edge { font-family: var(--mono); font-size: 12px; color: var(--muted); text-align: center; display: flex; flex-direction: column; }
.diagram-stat { font-size: 28px; font-weight: 600; letter-spacing: -.02em; }
.diagram-stat span { font-size: 15px; font-weight: 400; color: var(--muted); letter-spacing: 0; }
.diagram figcaption { font-size: 13px; color: var(--muted); }

/* Project list */
.filters { margin-top: 18px; display: flex; flex-wrap: wrap; gap: 8px; }
.filters[hidden] { display: none; }
.chip { font: inherit; font-size: 14px; min-height: 44px; padding: 0 18px; border-radius: 999px; border: 1px solid var(--line); background: transparent; color: var(--ink); cursor: pointer; }
.chip[aria-pressed="true"] { background: var(--ink); color: var(--bg); border-color: var(--ink); font-weight: 500; }
.projects { list-style: none; margin: 28px 0 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 440px), 1fr)); gap: 0 48px; }
.project { border-top: 1px solid var(--line); padding: 22px 0 24px; min-width: 0; }
.project[hidden] { display: none; }
.project img { width: 100%; height: auto; aspect-ratio: 16 / 10; object-fit: cover; object-position: top; border-radius: var(--radius); border: 1px solid var(--line); margin-bottom: 18px; background: var(--accent-soft); }
.project-head { display: flex; justify-content: space-between; align-items: baseline; gap: 16px; }
.project h4 { font-size: 18px; font-weight: 600; line-height: 1.35; }
.project-status { font-size: 13px; color: var(--muted); white-space: nowrap; }
.project-summary { margin-top: 6px; font-size: 15px; color: var(--muted); text-wrap: pretty; }
.project-impact { margin-top: 8px; font-size: 15px; font-weight: 600; color: var(--accent); }
.tags { list-style: none; margin: 10px 0 0; padding: 0; display: flex; flex-wrap: wrap; gap: 4px 14px; }
.tags li { font-family: var(--mono); font-size: 12.5px; color: var(--muted); }
.project-link { display: inline-block; margin-top: 6px; padding-block: 8px; font-size: 14px; font-weight: 500; }
.empty { margin-top: 24px; color: var(--muted); }

/* About */
.split { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 380px), 1fr)); gap: 48px 72px; }
.statement { margin-top: 20px; font-size: 20px; max-width: 34ch; text-wrap: pretty; }
.split .muted { margin-top: 18px; max-width: 52ch; }
.principles { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 28px; }
.principles h3 { font-size: 18px; font-weight: 600; }
.principles p { margin-top: 6px; font-size: 15px; color: var(--muted); }
.tools { margin-top: 18px; font-size: clamp(18px, 2.4vw, 22px); line-height: 1.6; max-width: 62ch; text-wrap: pretty; }
.tools strong { font-weight: 600; }
.tools .accent { color: var(--accent); }

/* Experience */
.job { margin-top: 36px; display: flex; flex-wrap: wrap; gap: 8px 48px; }
.job + .job { margin-top: 48px; padding-top: 36px; border-top: 1px solid var(--line); }
.job-period { flex: 1 1 180px; font-family: var(--mono); font-size: 14px; color: var(--muted); }
.job-body { flex: 999 1 520px; min-width: 0; }
.job-body h3 { font-size: 22px; font-weight: 600; }
.job-groups { margin-top: 16px; display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 240px), 1fr)); gap: 24px; }
.job-group-heading { font-weight: 600; }
.job-groups .muted { margin-top: 6px; font-size: 15px; }
.education { margin-top: 48px; font-size: 15px; }

/* Contact */
.contact-title { font-size: clamp(32px, 5vw, 44px); font-weight: 600; letter-spacing: -.03em; line-height: 1.1; max-width: 18ch; text-wrap: balance; }
.contact-links { margin-top: 32px; display: flex; flex-wrap: wrap; gap: 12px 28px; align-items: center; }
.contact-links a:not(.btn) { padding-block: 12px; font-size: 16px; }
.footer-note { margin-top: 64px; padding-top: 20px; border-top: 1px solid var(--line); font-size: 14px; color: var(--muted); }

/* Case study */
.case-title { margin-top: 14px; font-size: clamp(34px, 5vw, 48px); line-height: 1.1; letter-spacing: -.03em; font-weight: 600; max-width: 20ch; text-wrap: balance; }
.case-meta { margin-top: 40px; padding-block: 24px; border-block: 1px solid var(--line); }
.case-layout { margin-top: 64px; display: flex; flex-wrap: wrap; gap: 56px; align-items: flex-start; }
.case-toc { flex: 1 1 200px; }
.case-toc ol { list-style: none; margin: 8px 0 0; padding: 0; }
.case-toc a { display: block; padding-block: 8px; color: var(--ink); text-decoration: none; }
.case-body { flex: 999 1 640px; min-width: 0; max-width: 760px; display: flex; flex-direction: column; gap: 64px; }
.case-body h2 { font-size: 28px; font-weight: 600; letter-spacing: -.02em; margin-bottom: 16px; }
.case-body p + p { margin-top: 16px; }
.case-body .stats { margin-top: 0; }
.case-body .stats + p { margin-top: 20px; }
.table-wrap { margin-top: 20px; overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
table { width: 100%; min-width: 620px; border-collapse: collapse; font-size: 15px; }
th, td { text-align: left; padding: 14px 16px; vertical-align: top; }
th { border-bottom: 1px solid var(--line); font-weight: 600; }
.not-found h1 { font-size: clamp(32px, 5vw, 44px); letter-spacing: -.03em; }
.not-found .btn { margin-top: 28px; }