/* Reset, typography scale, links, focus, layout helpers */

*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.55;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main { flex: 1 0 auto; }

img, svg { display: block; max-width: 100%; }
[hidden] { display: none !important; }
button, input, select, textarea { font: inherit; color: inherit; }
ul, ol { padding: 0; }
::selection { background: var(--accent); color: var(--accent-contrast); }

/* type scale (kit: H1 44/500, H2 32/500, H3 24/500, H4 18/500, body 16/400, label 11 mono) */
h1, h2, h3, h4 { font-weight: 500; line-height: 1.15; letter-spacing: -0.02em; text-wrap: balance; }
h1 { font-size: clamp(34px, 5vw, 44px); line-height: 1.1; }
h2 { font-size: clamp(26px, 3.6vw, 32px); }
h3 { font-size: clamp(20px, 2.6vw, 24px); letter-spacing: -0.01em; }
h4 { font-size: 18px; letter-spacing: 0; }
p { max-width: 65ch; }

.mono, code, kbd { font-family: var(--font-mono); }

.label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
}
.label--green { color: var(--green); }

.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }

a {
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
  transition: color 0.15s;
}
a:hover { color: var(--accent); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

/* layout */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--section); }
.section--tight { padding-block: var(--section-tight); }
.section--alt { background: var(--bg); }
.section__head { margin-bottom: 40px; }
.section__head .label { margin-bottom: 12px; }

.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 100;
  padding: 10px 16px;
  background: var(--accent);
  color: var(--accent-contrast);
  border-radius: var(--radius);
  text-decoration: none;
}
.skip-link:focus { top: 12px; }

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0);
  white-space: nowrap; border: 0;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}