:root {
  /* Colours — Arctic Frost + ember */
  --ink: #0e1a2b;
  --ink-soft: #3a4a63;
  --paper: #fafafa;
  --paper-2: #f1f5fb;
  --card: #ffffff;
  --ice: #d4e4f7;
  --ice-deep: #a8c6e8;
  --steel: #4a6fa5;
  --steel-deep: #2b456f;
  --silver: #c0c0c0;
  --hairline: #e5ecf4;
  --ember: #e86a33;
  --ember-soft: #fde2d4;
  --beacon: #2ea8e5;
  --beacon-soft: #d6eefb;

  /* Gradients (ember rationed) */
  --grad-ink:   linear-gradient(180deg, #0e1a2b 0%, #17263d 100%);
  --grad-ember: linear-gradient(135deg, #e86a33 0%, #f39268 100%);
  --grad-ice:   linear-gradient(180deg, #f1f5fb 0%, #e3ecf7 100%);
  --grad-paper: linear-gradient(180deg, #ffffff 0%, #f4f7fc 100%);

  /* Spacing (rem) */
  --sp-xs: 0.25rem;
  --sp-sm: 0.5rem;
  --sp-md: 1rem;
  --sp-lg: 1.5rem;
  --sp-xl: 2rem;
  --sp-2xl: 3rem;
  --sp-3xl: 4rem;
  --sp-4xl: 6rem;

  /* Elevation */
  --shadow-1: 0 1px 2px rgba(14,26,43,.04), 0 2px 4px rgba(14,26,43,.04);
  --shadow-2: 0 4px 12px rgba(14,26,43,.06), 0 16px 32px rgba(14,26,43,.08);
  --shadow-ember: 0 12px 32px rgba(232,106,51,.18);

  /* Radii */
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 999px;

  /* Motion */
  --ease-out: cubic-bezier(.2,.7,.2,1);
  --ease-in-out: cubic-bezier(.4,0,.2,1);
  --dur-fast: 160ms;
  --dur-med:  320ms;
  --dur-slow: 520ms;

  /* Type */
  --font-display: "Fraunces", "Iowan Old Style", "Charter", Georgia, "Times New Roman", serif;
  --font-sans: "Inter", "DejaVu Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;

  --leading-tight: 1.05;
  --leading-snug:  1.2;
  --leading-body:  1.55;
  --tracking-tight: -0.02em;
  --tracking-normal: 0;
  --tracking-wide: 0.08em;

  /* Sticky header height (used for scroll-margin, hero offset) */
  --header-h: 68px;

  /* Responsive */
  --max-content: 72ch;
  --max-chart: 1100px;
  --max-page: 1240px;
}

@media (max-width: 720px) {
  :root {
    --header-h: 56px;
    --sp-4xl: 3.5rem;
  }
}