/* Reset */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { min-height: 100%; }
html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background: var(--bg);   /* prevents white flash during load */
}
img, svg, canvas, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; padding: 0; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }

/* Font face — self-hosted Hanken Grotesk variable */
@font-face {
  font-family: 'Hanken Grotesk';
  src: url('../fonts/HankenGrotesk-Variable.woff2') format('woff2-variations');
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

/* Body — dark-first */
body {
  font-family: var(--font-body);
  font-size: var(--type-base);
  font-weight: var(--w-body);
  line-height: var(--lh-normal);
  background: var(--bg);
  color: var(--fg);
  overflow-x: hidden;
  -webkit-text-size-adjust: 100%;
}

/* Selection — yellow on ink */
::selection { background: var(--emphasis); color: var(--bg); }

/* Film grain — calibrated for dark base (monochrome luminance noise) */
body::after {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 9999;
  pointer-events: none;
  opacity: 0.04;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 256px 256px;
  mix-blend-mode: overlay;
}

/* Accessibility */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0, 0, 0, 0);
  white-space: nowrap; border: 0;
}

.skip-link {
  position: absolute;
  top: -100px; left: var(--space-4);
  padding: var(--space-3) var(--space-6);
  background: var(--emphasis); color: var(--bg);
  font-weight: var(--w-heading); z-index: 10001;
  transition: top var(--dur-fast) var(--ease-snap);
}
.skip-link:focus { top: var(--space-4); }

/* Focus ring — yellow on dark */
:focus-visible {
  outline: 2px solid var(--emphasis);
  outline-offset: 3px;
}

/* Layout container */
.container {
  width: 100%;
  max-width: 90rem;
  margin-inline: auto;
  padding-inline: var(--space-6);
}
@media (min-width: 768px) {
  .container { padding-inline: var(--space-12); }
}

/* MONO LABELS — bracketed meta tags, route chrome, timestamps */
.mono-label {
  font-family: var(--font-mono);
  font-size: var(--type-xs);
  letter-spacing: var(--ls-mono-label);
  text-transform: uppercase;
  color: var(--fg-subtle);
  font-weight: 400;
}

/* SECTION LABEL — copper prefix line + mono label (brand signature per §14 do-rules) */
.section-label {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  font-family: var(--font-mono);
  font-size: var(--type-xs);
  letter-spacing: var(--ls-mono-label);
  text-transform: uppercase;
  color: var(--fg-muted);
  margin-bottom: var(--space-8);
}
.section-label::before {
  content: '';
  width: var(--space-8);
  height: 1px;
  background: var(--signal);
}

/* BRACKETED META TAG — [LAB] [EST. 2024] style */
.bracket-tag {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--type-xs);
  letter-spacing: var(--ls-mono-bracket);
  color: var(--fg-subtle);
}
.bracket-tag::before { content: '['; color: var(--signal); }
.bracket-tag::after { content: ']'; color: var(--signal); }

/* Topographic pattern layer helper */
.pattern-layer {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image: url('../patterns/BG-Pattern-LightBlue.png');
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center;
  opacity: 0.2;
}
.pattern-layer--yellow {
  background-image: url('../patterns/BG-Pattern-LightYellow.png');
  opacity: 0.15;
}

/* Site chrome (persistent mono label bottom-right) */
.site-chrome {
  position: fixed;
  bottom: var(--space-4);
  right: var(--space-4);
  font-family: var(--font-mono);
  font-size: var(--type-xs);
  letter-spacing: var(--ls-mono-label);
  color: var(--fg-subtle);
  z-index: 50;
  display: flex;
  gap: var(--space-1);
}
.site-chrome .route { color: var(--signal); }

/* YELLOW PILL BUTTON — primary CTA per brand (no rounded > 3px rule) */
.btn-yellow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-6);
  background: var(--emphasis);
  color: var(--bg);
  font-weight: var(--w-heading);
  font-size: var(--type-sm);
  border-radius: 999px;
  transition: transform var(--dur-fast) var(--ease-snap);
}
.btn-yellow:hover { transform: translateY(-2px); }

/* HERO-EXCLUSIVE TYPOGRAPHIC CLASS — weight 900 restricted by brand */
.hero-display {
  font-family: var(--font-display);
  font-weight: var(--w-hero);
  line-height: var(--lh-tight);
  letter-spacing: var(--ls-display);
}