/* Portfolio design system: one stylesheet, no framework, no JavaScript.
   Colour tokens live on :root and are swapped for dark mode below. */

:root {
  --bg: #fbfbf9;
  --surface: #ffffff;
  --fg: #16181d;
  --muted: #555c68;
  --faint: #8a909b;
  --line: #e4e4df;
  --accent: #1f4e8c;
  --accent-soft: #eaf0f8;
  --radius: 10px;
  --max: 1040px;
  --sans: ui-sans-serif, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, Consolas, monospace;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1216;
    --surface: #151a20;
    --fg: #e6e8ec;
    --muted: #a2a9b5;
    --faint: #7b8391;
    --line: #262d36;
    --accent: #8fb4ea;
    --accent-soft: #17222f;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 var(--sans);
  text-rendering: optimizeLegibility;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent); text-underline-offset: 3px; text-decoration-thickness: 1px; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

.skip { position: absolute; left: -9999px; top: 8px; background: var(--surface); padding: 8px 12px; border: 1px solid var(--line); }
.skip:focus { left: 16px; z-index: 10; }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 24px; }
@media (max-width: 600px) { .wrap { padding: 0 16px; } }

/* ---------- header ---------- */
.site-head { border-bottom: 1px solid var(--line); background: var(--bg); position: sticky; top: 0; z-index: 5; }
.site-head .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 60px; }
.brand { font-weight: 650; color: var(--fg); text-decoration: none; letter-spacing: .1px; }
.nav { display: flex; gap: 22px; align-items: center; flex-wrap: wrap; }
.nav a { color: var(--muted); text-decoration: none; font-size: 15px; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--fg); }
.nav .cv { color: var(--fg); border: 1px solid var(--line); padding: 5px 12px; border-radius: 999px; }
@media (max-width: 720px) { .nav a:not(.cv) { display: none; } }

/* ---------- type ---------- */
h1, h2, h3 { line-height: 1.2; margin: 0; font-weight: 650; letter-spacing: -.2px; }
h1 { font-size: clamp(30px, 4.4vw, 42px); }
h2 { font-size: 24px; }
h3 { font-size: 19px; }
p { margin: 0 0 12px; }
.label { font: 500 12px/1.4 var(--mono); text-transform: uppercase; letter-spacing: .9px; color: var(--faint); margin: 0 0 10px; }
.muted { color: var(--muted); }
.small { font-size: 14px; }

/* ---------- hero ---------- */
.hero { padding-top: 64px; padding-bottom: 40px; }
.hero-grid { display: grid; grid-template-columns: 1fr 220px; gap: 48px; align-items: center; }
.hero .lead { font-size: 21px; line-height: 1.5; margin: 14px 0 12px; max-width: 34em; }
.hero .meta { color: var(--muted); margin: 0 0 6px; }
.hero .avail { display: inline-flex; align-items: center; gap: 8px; color: var(--muted); font-size: 15px; margin: 4px 0 22px; }
.hero .avail::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: #2f9e62; }
.portrait { border-radius: var(--radius); border: 1px solid var(--line); aspect-ratio: 4 / 5; object-fit: cover; }
@media (max-width: 760px) {
  .hero { padding-top: 36px; }
  .hero-grid { grid-template-columns: 1fr; gap: 20px; }
  .hero-grid .portrait { width: 112px; order: -1; border-radius: 50%; aspect-ratio: 1; object-position: 50% 18%; }
}

.btns { display: flex; flex-wrap: wrap; gap: 10px; }
.btn { display: inline-flex; align-items: center; gap: 6px; padding: 9px 16px; border-radius: 8px; border: 1px solid var(--line); color: var(--fg); text-decoration: none; font-size: 15px; background: var(--surface); }
.btn:hover { border-color: var(--faint); }
.btn.primary { background: var(--fg); color: var(--bg); border-color: var(--fg); }

/* ---------- highlights ---------- */
.proof { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; margin: 8px 0 0; }
.proof > div { background: var(--surface); padding: 16px 18px; }
.proof b { display: block; font-size: 15px; margin-bottom: 2px; }
.proof span { color: var(--muted); font-size: 14px; }
@media (max-width: 760px) { .proof { grid-template-columns: 1fr; } }

/* ---------- sections ---------- */
section { padding: 44px 0; border-top: 1px solid var(--line); }
.sec-head { margin-bottom: 22px; }
.sec-head p { color: var(--muted); max-width: 40em; margin-top: 8px; }

/* ---------- project cards ---------- */
.cards { display: grid; gap: 16px; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px 24px; display: grid; grid-template-columns: 170px 1fr; gap: 24px; }
.card .kind { font: 500 12px/1.5 var(--mono); text-transform: uppercase; letter-spacing: .8px; color: var(--faint); }
.card .kind b { display: block; color: var(--accent); font-weight: 600; }
.card h3 { margin-bottom: 8px; }
.card p { color: var(--muted); }
.facts { display: flex; flex-wrap: wrap; gap: 6px 14px; margin: 0 0 12px; padding: 0; list-style: none; font-size: 14px; }
.facts li { color: var(--fg); }
.facts li + li::before { content: "·"; color: var(--faint); margin-right: 14px; }
.stack { font: 13px/1.6 var(--mono); color: var(--faint); margin: 0 0 12px; }
.links { display: flex; flex-wrap: wrap; gap: 16px; font-size: 15px; }
.note { font-size: 13px; color: var(--faint); }
@media (max-width: 760px) { .card { grid-template-columns: 1fr; gap: 8px; padding: 18px; } }

/* ---------- compact list ---------- */
.rows { list-style: none; margin: 0; padding: 0; }
.rows li { display: grid; grid-template-columns: 170px 1fr; gap: 24px; padding: 14px 0; border-bottom: 1px solid var(--line); }
.rows li:last-child { border-bottom: 0; }
.rows .when { color: var(--faint); font: 13px/1.6 var(--mono); }
.rows .what b { display: block; }
.rows .what span { color: var(--muted); font-size: 15px; }
@media (max-width: 760px) { .rows li { grid-template-columns: 1fr; gap: 2px; } }

/* ---------- skills ---------- */
.skills { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.skills div { border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px; background: var(--surface); }
.skills p { margin: 0; color: var(--muted); font-size: 15px; }
@media (max-width: 760px) { .skills { grid-template-columns: 1fr; } }

/* ---------- research / case study ---------- */
.formula { font: 16px/1.5 var(--mono); background: var(--accent-soft); border-radius: 8px; padding: 12px 16px; overflow-x: auto; margin: 0 0 14px; }
table { width: 100%; border-collapse: collapse; font-size: 15px; margin: 6px 0 12px; }
th, td { text-align: left; padding: 9px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { font-weight: 600; color: var(--muted); font-size: 13px; text-transform: uppercase; letter-spacing: .5px; }
td.num { font-variant-numeric: tabular-nums; white-space: nowrap; }
.table-scroll { overflow-x: auto; }

.article { max-width: 760px; }
.article h2 { margin: 36px 0 12px; font-size: 22px; }
.article h3 { margin: 22px 0 8px; font-size: 17px; }
.article ul { padding-left: 20px; margin: 0 0 14px; }
.article li { margin-bottom: 6px; }
.article figure { margin: 18px 0; }
.article figcaption { color: var(--faint); font-size: 13px; margin-top: 8px; }
.shot { border: 1px solid var(--line); border-radius: var(--radius); }
.kv { display: grid; grid-template-columns: 150px 1fr; gap: 6px 18px; font-size: 15px; margin: 18px 0 8px; }
.kv dt { color: var(--faint); }
.kv dd { margin: 0; }
@media (max-width: 600px) { .kv { grid-template-columns: 1fr; gap: 0 0; } .kv dd { margin-bottom: 8px; } }
.back { display: inline-block; margin: 28px 0 8px; font-size: 15px; }

.diagram { width: 100%; height: auto; color: var(--fg); }
.diagram rect { fill: var(--surface); stroke: var(--line); }
.diagram .hl rect { stroke: var(--accent); }
.diagram text { fill: currentColor; font: 13px var(--sans); }
.diagram .sub { fill: var(--muted); font-size: 11.5px; }
.diagram path, .diagram line { stroke: var(--faint); fill: none; }
.diagram .arrow { fill: var(--faint); stroke: none; }

/* ---------- footer ---------- */
.site-foot { border-top: 1px solid var(--line); padding: 26px 0 40px; color: var(--faint); font-size: 14px; }
.site-foot .wrap { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
.site-foot a { color: var(--muted); }