:root {
  --bg: #faf9f6;
  --surface: #ffffff;
  --ink: #1c1e23;
  --ink-2: #454a54;
  --muted: #6b7079;
  --rule: #e5e2db;
  --accent: #2459c4;
  --accent-soft: #e8eefb;
  --warm: #c2531e;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(20, 22, 28, .06), 0 4px 14px rgba(20, 22, 28, .05);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111215;
    --surface: #1a1c21;
    --ink: #ecedef;
    --ink-2: #c4c8cf;
    --muted: #979ea9;
    --rule: #2b2e35;
    --accent: #7aa7ff;
    --accent-soft: #1c2740;
    --warm: #f08a55;
    --shadow: none;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.6 var(--font);
}
a { color: var(--accent); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
img { max-width: 100%; height: auto; }

.wrap { max-width: 1040px; margin: 0 auto; padding: 0 20px; }
.narrow { max-width: 740px; }

/* header */
.site-head { border-bottom: 1px solid var(--rule); }
.site-head .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 60px;
                   flex-wrap: wrap; }
.brand { font-weight: 700; color: var(--ink); text-decoration: none; letter-spacing: -.01em; }
.site-head nav { display: flex; gap: 18px; flex-wrap: wrap; font-size: 15px; }
.site-head nav a { color: var(--ink-2); text-decoration: none; }
.site-head nav a:hover { color: var(--accent); }

/* hero */
.hero { padding: 64px 0 40px; }
.hero h1 { font-size: clamp(34px, 6vw, 52px); line-height: 1.1; letter-spacing: -.02em; margin: 0 0 18px; }
.hero .lead { font-size: clamp(18px, 2.4vw, 21px); color: var(--ink-2); max-width: 680px; margin: 0 0 14px; }
.hero .now { color: var(--muted); font-size: 15px; margin: 0 0 24px; }
.pills { display: flex; gap: 10px; flex-wrap: wrap; padding: 0; margin: 0; list-style: none; }
.pill { display: inline-flex; align-items: center; gap: 8px; padding: 8px 14px; border-radius: 999px;
        border: 1px solid var(--rule); background: var(--surface); color: var(--ink); text-decoration: none;
        font-size: 15px; }
.pill:hover { border-color: var(--accent); color: var(--accent); }
.pill svg { width: 16px; height: 16px; fill: currentColor; }

/* sections */
section { padding: 36px 0; }
h2 { font-size: 26px; letter-spacing: -.01em; margin: 0 0 6px; }
.kicker { color: var(--muted); margin: 0 0 22px; }
h3 { font-size: 18px; margin: 0 0 6px; line-height: 1.35; }

.grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.card { background: var(--surface); border: 1px solid var(--rule); border-radius: var(--radius); padding: 20px;
        box-shadow: var(--shadow); display: flex; flex-direction: column; }
.card p { margin: 0 0 10px; color: var(--ink-2); font-size: 16px; }
.card .meta { margin-top: auto; font-size: 14px; color: var(--muted); }
.card .tags { margin-top: auto; padding-top: 8px; }
.card .tags .tag { margin-bottom: 4px; }
.card .links { margin-top: auto; display: flex; gap: 14px; font-size: 15px; flex-wrap: wrap; }
.nowrap { white-space: nowrap; }
.big-number { font-size: 30px; font-weight: 750; letter-spacing: -.02em; color: var(--accent); line-height: 1.1;
              margin-bottom: 6px; }
.tag { display: inline-block; font: 12px/1.6 var(--mono); color: var(--muted); border: 1px solid var(--rule);
       border-radius: 6px; padding: 0 6px; margin: 0 6px 8px 0; }
.featured { border-color: var(--accent); }
.badge { font: 12px/1.6 var(--mono); color: var(--warm); }

.list { list-style: none; padding: 0; margin: 0; display: grid; gap: 14px; }
.list li { border-left: 3px solid var(--rule); padding: 2px 0 2px 16px; }
.list li strong { display: block; }
.list .when { color: var(--muted); font-size: 14px; }
.list p { margin: 4px 0 0; color: var(--ink-2); font-size: 16px; }

.two-col { display: grid; gap: 28px; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }

.site-foot { border-top: 1px solid var(--rule); margin-top: 32px; padding: 26px 0 40px; color: var(--muted);
             font-size: 14px; }

/* write-up pages */
.article { padding: 48px 0 24px; }
.article h1 { font-size: clamp(30px, 5vw, 44px); line-height: 1.15; letter-spacing: -.02em; margin: 0 0 14px; }
.article .lead { font-size: 20px; color: var(--ink-2); margin: 0 0 18px; }
.note { background: var(--accent-soft); border-radius: 10px; padding: 12px 16px; font-size: 15px; color: var(--ink-2); }
.finding { padding: 26px 0; border-top: 1px solid var(--rule); }
.finding h2 { font-size: 22px; }
.finding .num { color: var(--muted); font: 13px var(--mono); display: block; margin-bottom: 4px; }
figure { margin: 18px 0 0; background: #fff; border-radius: 10px; padding: 10px; border: 1px solid var(--rule); }
figure img { display: block; margin: 0 auto; }
figure.tall img { max-width: 640px; width: 100%; }
figcaption { font-size: 13px; color: #5a5f69; padding: 8px 4px 0; }
.credits { font-size: 14px; color: var(--muted); }
.credits img { height: 14px; width: auto; vertical-align: middle; }
.back { font-size: 15px; }

@media (max-width: 560px) {
  body { font-size: 16px; }
  .hero { padding: 40px 0 28px; }
  .site-head nav { gap: 12px; }
}