/* ============================================================
   6G ROADMAP TRAINING — DESIGN TOKENS  (white cinematic studio)
   Shared by the shell (index.html) and every day player.
   Each 6G concept owns one colour, so the eye learns the topic
   by its hue — the way a good teacher colour-codes a whiteboard.
   ============================================================ */
:root{
  /* — Surfaces — */
  --bg:#ffffff;
  --bg-soft:#f7f9fc;
  --bg-panel:#f1f5f9;
  --bg-elevated:#e7edf5;
  --line:#e2e8f0;
  --line-strong:#cbd5e1;

  /* — Ink (text on white) — */
  --ink:#0f172a;
  --ink-2:#334155;
  --ink-3:#64748b;
  --ink-4:#94a3b8;
  --spec:#64748b;

  /* — Concept colours (the teaching palette) — */
  --c-evo:#2563eb;        /* evolution / mobile broadband — blue   */
  --c-vision:#7c3aed;     /* IMT-2030 vision — violet              */
  --c-scenario:#0d9488;   /* usage scenarios — teal                */
  --c-kpi:#d97706;        /* KPIs / numbers — amber                */
  --c-global:#db2777;     /* global ecosystem — pink               */
  --c-3gpp:#0891b2;       /* 3GPP / standards — cyan               */

  --c-subthz:#db2777;     --c-midband:#2563eb;  --c-ris:#65a30d;
  --c-ainative:#7c3aed;   --c-isac:#0d9488;     --c-ntn:#0284c7;
  --c-twin:#4f46e5;       --c-pqc:#e11d48;

  --ok:#16a34a; --warn:#ea580c; --err:#dc2626; --gold:#d97706;

  /* — Day signature colours (sidebar + stage accents) — */
  --day1:#2563eb;  --day2:#0891b2;  --day3:#db2777;
  --day4:#7c3aed;  --day5:#059669;

  /* — Type — */
  --font:"Inter","Segoe UI",system-ui,-apple-system,sans-serif;
  --mono:"JetBrains Mono","Fira Code",ui-monospace,monospace;

  /* — Radius / shadow / motion — */
  --r-sm:8px; --r:14px; --r-lg:22px; --r-xl:30px;
  --sh-1:0 1px 2px rgba(15,23,42,.04),0 1px 3px rgba(15,23,42,.06);
  --sh-2:0 6px 18px rgba(15,23,42,.06),0 2px 6px rgba(15,23,42,.05);
  --sh-3:0 24px 60px rgba(15,23,42,.12),0 8px 24px rgba(15,23,42,.08);
  --sh-glow:0 0 0 1px rgba(37,99,235,.15),0 12px 40px rgba(37,99,235,.18);
  --ease:cubic-bezier(.22,.61,.36,1);
  --ease-out:cubic-bezier(.16,1,.3,1);
}

*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{font-family:var(--font);color:var(--ink);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
::selection{background:rgba(124,58,237,.18)}