/* ════════════════════════════════════════════════════════════════════
   Sightline · Colors
   Earth-toned, paper-first. Bone is the ground — white is forbidden.
   Ochre is the Sightline accent; Glacial is the Academic Intelligence
   (product) accent. Status colours indicate STATE only, never decoration.
   ════════════════════════════════════════════════════════════════════ */

:root {
  /* ── Paper & ink (neutrals) ──────────────────────────────────────── */
  --bone:        #F2EEE6;   /* primary surface — the paper */
  --bone-2:      #E8E2D5;   /* inset / card ground */
  --bone-3:      #DED7C7;   /* deeper inset, dividers on bone */
  --ink:         #14110D;   /* type & primary dark surface */
  --ink-soft:    #2A251D;   /* raised dark surface */

  /* ── Ochre — Sightline accent (the watershed at evening) ─────────── */
  --ochre-glow:  #E8B97A;   /* tint / wash */
  --ochre:       #B8732C;   /* core — the wordmark dot, the accent */
  --ochre-deep:  #6B3F12;   /* emphasis / hover */

  /* ── Glacial — Academic Intelligence accent ─────────────────────── */
  --glacial-glow: #7AAFC4;
  --glacial:      #2B4A5A;  /* core */
  --glacial-deep: #142935;  /* dark surface */
  --glacial-ink:  #0E1F2A;  /* deepest */

  /* ── Frost — PRODUCT-ONLY tints (never on a Sightline surface) ───── */
  --frost:    #E9EFF2;
  --frost-2:  #D8E2E8;
  --frost-3:  #BDCBD3;

  /* ── Status · Moss (positive · go · ok) ──────────────────────────── */
  --moss-glow:    #D4DEC2;
  --moss:         #6B8147;
  --moss-deep:    #3E4F26;
  --moss-on-dark: #B7CC8A;

  /* ── Status · Amber (caution · hold · pending) ───────────────────── */
  --amber-glow:    #F0DC9F;
  --amber:         #B0851D;
  --amber-deep:    #6B500F;
  --amber-on-dark: #E8C766;

  /* ── Status · Brick (negative · stop · error) ────────────────────── */
  --brick-glow:    #EBC4B8;
  --brick:         #A8392A;
  --brick-deep:    #5E1C13;
  --brick-on-dark: #E89A8C;

  /* ── Status · Info (informational · neutral) — uses glacial ──────── */
  --info-glow:    #7AAFC4;
  --info:         #2B4A5A;
  --info-deep:    #142935;
  --info-on-dark: #A6CBDB;

  /* ── Hairlines & foreground steps (on bone) ──────────────────────── */
  --hairline:        color-mix(in srgb, var(--ink) 12%, transparent);
  --hairline-strong: color-mix(in srgb, var(--ink) 24%, transparent);
  --fg-muted:        color-mix(in srgb, var(--ink) 60%, transparent);
  --fg-faint:        color-mix(in srgb, var(--ink) 40%, transparent);

  /* ── Semantic aliases ────────────────────────────────────────────── */
  --surface-page:   var(--bone);
  --surface-inset:  var(--bone-2);
  --surface-dark:   var(--ink);
  --text-body:      var(--ink);
  --text-muted:     var(--fg-muted);
  --text-faint:     var(--fg-faint);
  --text-on-dark:   var(--bone);
  --accent:         var(--ochre);
  --accent-deep:    var(--ochre-deep);
  --accent-glow:    var(--ochre-glow);
  --accent-2:       var(--glacial);
  --border:         var(--hairline);
  --border-strong:  var(--hairline-strong);
}

/* ── Brand scope: Academic Intelligence (product) ──────────────────────
   Wrap a product surface in [data-brand="ai"] to swap the accent to Glacial
   and unlock the Frost product tints. */
[data-brand="ai"] {
  --accent:      var(--glacial);
  --accent-deep: var(--glacial-deep);
  --accent-glow: var(--glacial-glow);
}

/* ── On-dark surfaces: hairlines/foregrounds invert against bone ─────── */
[data-surface="dark"] {
  --hairline:        color-mix(in srgb, var(--bone) 18%, transparent);
  --hairline-strong: color-mix(in srgb, var(--bone) 36%, transparent);
  --fg-muted:        color-mix(in srgb, var(--bone) 65%, transparent);
  --fg-faint:        color-mix(in srgb, var(--bone) 42%, transparent);
  --text-body:       var(--bone);
  color: var(--bone);
}