/* planck4.com styles. System fonts only: the site's CSP allows no external fonts or scripts. */
:root {
  --bg: #0b0f14;
  --bg-raised: #121821;
  --line: #1f2833;
  --fg: #e7edf3;
  --muted: #8b97a4;
  --accent: #4f8cff;
  --accent-hover: #3a78ee;
  --radius: 12px;
  --max: 1040px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "Cascadia Code", "SF Mono", Consolas, monospace;
}

* { box-sizing: border-box; }

html { color-scheme: dark; }

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 var(--font);
}

a { color: var(--accent); }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }
code { font: 0.9em var(--mono); overflow-wrap: anywhere; }

.container { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 24px; }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(11, 15, 20, 0.78);
  backdrop-filter: saturate(160%) blur(12px);
  -webkit-backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  height: 64px;
}

/* Wordmark: small glowing accent square + name */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--fg);
  text-decoration: none;
  font: 600 18px/1 var(--mono);
  letter-spacing: -0.02em;
}
.brand-mark {
  width: 14px;
  height: 14px;
  border-radius: 3px;
  background: var(--accent);
  box-shadow: 0 0 18px rgba(79, 140, 255, 0.55);
}

.nav { display: flex; align-items: center; gap: 4px; }
.nav a {
  padding: 8px 14px;
  border-radius: 999px;
  color: var(--muted);
  text-decoration: none;
  font-size: 15px;
  font-weight: 500;
}
.nav a:hover,
.nav a[aria-current="page"] { color: var(--fg); background: var(--bg-raised); }

/* ---------- Main ---------- */
main { flex: 1; }

.hero { padding: 96px 0 72px; }
.hero h1 {
  margin: 0;
  font-size: clamp(2.6rem, 7vw, 4.5rem);
  line-height: 1.05;
  letter-spacing: -0.035em;
  text-wrap: balance;
}
.hero .lede { margin: 16px 0 0; max-width: 34rem; color: var(--muted); font-size: 1.15rem; }
.eyebrow {
  display: inline-block;
  margin-bottom: 14px;
  color: var(--accent);
  font: 500 13px/1 var(--mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 20px; margin-top: 32px; }

.button {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  text-decoration: none;
}
.button:hover { background: var(--accent-hover); }
.button-ghost { background: transparent; color: var(--fg); border: 1px solid var(--line); }
.button-ghost:hover { background: var(--bg-raised); }

.meta { color: var(--muted); font-size: 0.9rem; }

/* ---------- Sections ---------- */
.section { padding: 8px 0 72px; }
.section h2 { margin: 0 0 20px; font-size: 1.1rem; letter-spacing: -0.01em; }

.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px; }

/* Project card: the whole card is the link */
.card {
  display: grid;
  gap: 8px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-raised);
  color: var(--fg);
  text-decoration: none;
}
.card:hover { border-color: var(--accent); }
.card h3 { margin: 0; font-size: 1.25rem; letter-spacing: -0.01em; }
.card p { margin: 0; color: var(--muted); }
.card .card-link { margin-top: 8px; color: var(--accent); font-weight: 600; }

.panels { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 16px; }
.panel {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-raised);
}
.panel h2 { margin: 0 0 10px; font-size: 1.05rem; }
.panel ol { margin: 0; padding-left: 20px; }
.panel p { margin: 0; }
.panel .note { margin-top: 12px; color: var(--muted); font-size: 0.92rem; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line); }
.site-footer .container {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px;
  padding-top: 24px;
  padding-bottom: 24px;
  color: var(--muted);
  font-size: 0.9rem;
}
.site-footer a { color: var(--muted); }

@media (max-width: 560px) {
  .hero { padding: 64px 0 48px; }
  .nav a { padding: 8px 10px; }
}