:root{
    --bg:#0b0e14; --panel:#141a24; --panel2:#1b2330; --line:#27303f;
    --text:#e6edf3; --muted:#8b98a9; --accent:#f7931a; --accent2:#3fb950;
    --blue:#58a6ff; --red:#f85149; --radius:14px;
    --banner-grad:linear-gradient(120deg,#0c1322 0%,#13233c 52%,#3a2a14 100%);
  }
  [data-theme="dark"]{
    --bg:#0b0e14; --panel:#141a24; --panel2:#1b2330; --line:#27303f;
    --text:#e6edf3; --muted:#8b98a9; --accent:#f7931a; --accent2:#3fb950;
    --blue:#58a6ff; --red:#f85149;
    --banner-grad:linear-gradient(120deg,#0c1322 0%,#13233c 52%,#3a2a14 100%);
  }
  [data-theme="light"]{
    --bg:#f4f6fb; --panel:#ffffff; --panel2:#eef1f7; --line:#d8dee9;
    --text:#1b2330; --muted:#5b6675; --accent:#e8820e; --accent2:#1a9e4b;
    --blue:#2563eb; --red:#dc2626;
    --banner-grad:linear-gradient(120deg,#172033 0%,#243349 52%,#5b4420 100%);
  }
  [data-theme="ocean"]{
    --bg:#071726; --panel:#0d2233; --panel2:#123048; --line:#1d4257;
    --text:#e3f1fb; --muted:#8fb0c4; --accent:#38bdf8; --accent2:#22d3ee;
    --blue:#60a5fa; --red:#fb7185;
    --banner-grad:linear-gradient(120deg,#041320 0%,#072c44 55%,#0a4a5c 100%);
  }
  [data-theme="forest"]{
    --bg:#0a140f; --panel:#10211a; --panel2:#163024; --line:#244536;
    --text:#e6f3ea; --muted:#94b3a2; --accent:#4ade80; --accent2:#a3e635;
    --blue:#34d399; --red:#f87171;
    --banner-grad:linear-gradient(120deg,#06130d 0%,#0c2a1c 55%,#1a3a24 100%);
  }
  [data-theme="grape"]{
    --bg:#140c1f; --panel:#1e1330; --panel2:#291a40; --line:#3a2a52;
    --text:#f1e9fb; --muted:#a996c0; --accent:#c084fc; --accent2:#f0abfc;
    --blue:#a78bfa; --red:#fb7185;
    --banner-grad:linear-gradient(120deg,#0f0820 0%,#241140 55%,#3a1a3f 100%);
  }
  body{transition:background .3s,color .3s}
  *{box-sizing:border-box}
  body{margin:0;background:var(--bg);color:var(--text);
    font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
    line-height:1.6;font-size:16px}
  a{color:var(--blue)}
  /* ---- Suite-consistent slim header/footer (replaces the old hero banner —
     same bar height/padding/font convention as CryptoPro Trader and Charts,
     see Suite CLAUDE.md rule 17) ---- */
  .site-header{background:var(--panel);border-bottom:1px solid var(--line);
    padding:16px 24px;display:flex;justify-content:space-between;align-items:center;
    gap:16px;flex-wrap:wrap;position:sticky;top:0;z-index:100}
  .brand{display:flex;align-items:center;gap:6px;font-size:13px;font-weight:700;color:var(--text)}
  .brand-cp{color:var(--accent)}
  .brand img{width:18px;height:18px;border-radius:4px;vertical-align:middle}
  .header-right{display:flex;align-items:center;gap:16px;flex-wrap:wrap}
  .themes{display:flex;align-items:center;gap:7px}
  .themes .tname{font-size:.74rem;color:var(--muted);min-width:52px;text-align:right}
  .swatch{width:20px;height:20px;border-radius:50%;cursor:pointer;border:2px solid var(--line);
    padding:0;transition:transform .15s,border-color .15s;position:relative}
  .swatch:hover{transform:scale(1.15)}
  .swatch.active{border-color:var(--text);box-shadow:0 0 0 2px rgba(127,127,127,.25)}
  .swatch.active::after{content:"✓";position:absolute;inset:0;display:grid;place-items:center;
    font-size:.6rem;color:#fff;text-shadow:0 1px 2px rgba(0,0,0,.9)}
  .levelpick{display:flex;align-items:center;gap:8px}
  .levelpick .lvl-title{font-size:.68rem;text-transform:uppercase;letter-spacing:.7px;color:var(--muted);font-weight:700}
  .levelpick .lvl-desc{display:none}
  .levelpick .levels{display:flex;gap:5px}
  .levelpick .levels button{border:1px solid var(--accent);background:transparent;color:var(--accent);padding:5px 10px;border-radius:8px;cursor:pointer;font-size:.78rem;font-weight:700;white-space:nowrap;transition:.15s}
  .levelpick .levels button:hover{background:rgba(127,127,127,.12)}
  .levelpick .levels button.active{background:var(--accent);color:#0b0e14;border-color:var(--accent)}
  .page-intro{max-width:1120px;margin:0 auto;padding:20px 18px 4px}
  .page-intro p{margin:0;color:var(--muted);font-size:.92rem;line-height:1.45;max-width:760px}
  .banner-stats{display:flex;gap:6px;flex-wrap:wrap;margin-top:10px}
  .banner-stats span{background:var(--panel2);border:1px solid var(--line);
    border-radius:99px;padding:3px 9px;font-size:.72rem;color:var(--muted)}
  .quizbar{display:flex;flex-wrap:wrap;gap:6px 18px;align-items:center;
    font-size:.8rem;color:var(--muted);margin-top:10px}
  .quizbar .qb-label{font-weight:700;text-transform:uppercase;letter-spacing:.6px;font-size:.68rem;color:var(--muted)}
  .quizbar b{color:var(--text)}
  .quizbar .qb-acc{color:var(--accent2)}
  .quizbar .qb-muted{color:var(--muted)}
  @media (max-width:720px){.site-header{padding:12px 16px}}
  .wrap{max-width:1120px;margin:0 auto;padding:14px 18px 60px}
  .site-footer{color:var(--muted);font-size:12px;padding:16px 24px;border-top:1px solid var(--line);
    display:flex;flex-wrap:wrap;align-items:center;gap:4px 14px;text-align:left}
  .site-footer .footer-name{display:inline-flex;align-items:center;gap:6px;font-weight:700;color:var(--text);font-size:13px}
  .site-footer .footer-logo-icon{width:18px;height:18px;border-radius:4px;vertical-align:middle}
  .site-footer .footer-studio{display:inline-flex;align-items:center;gap:6px}
  .site-footer .footer-sep{color:var(--line)}
  .footer-donate{color:#e0b45c;text-decoration:none}
  .footer-donate:hover{color:#f0c876}
  .progress-box{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);
    padding:11px 14px;margin:12px 0;display:flex;align-items:center;gap:16px;flex-wrap:wrap}
  .bar{flex:1;min-width:180px;height:12px;background:var(--panel2);border-radius:99px;overflow:hidden}
  .bar > i{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--accent),var(--accent2));
    transition:width .4s ease}
  .progress-box b{font-size:1.05rem}
  .reset{background:none;border:1px solid var(--line);color:var(--muted);padding:6px 12px;
    border-radius:8px;cursor:pointer;font-size:.8rem}
  .reset:hover{color:var(--text);border-color:var(--muted)}
  .track{margin:20px 0 0}
  .track > h2{display:flex;align-items:center;gap:10px;font-size:1.25rem;margin:0 0 4px;
    padding-bottom:8px;border-bottom:2px solid var(--line);cursor:pointer;user-select:none}
  .track > h2{border-bottom:none;position:relative}
  .track > h2::after{content:"";position:absolute;left:0;right:0;bottom:0;height:2px;
    background:linear-gradient(90deg,var(--accent),transparent)}
  .track .tnum{background:var(--accent);color:#000;font-weight:700;border-radius:8px;
    width:30px;height:30px;display:grid;place-items:center;font-size:.95rem}
  .track .ticon{font-size:1.3rem;line-height:1}
  .track .tchev{margin-left:auto;color:var(--muted);transition:transform .25s;font-size:1rem}
  .track:not(.collapsed) .tchev{transform:rotate(90deg)}
  .track.collapsed .track-body{display:none}
  .track .tsub{color:var(--muted);font-size:.9rem;margin:2px 0 10px}
  .module{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);
    margin:10px 0;overflow:hidden}
  .mhead{display:flex;align-items:center;gap:12px;padding:11px 14px;cursor:pointer;user-select:none}
  .mhead:hover{background:var(--panel2)}
  .check{width:22px;height:22px;border-radius:50%;border:2px solid var(--line);flex:none;
    display:grid;place-items:center;font-size:.8rem;color:transparent;transition:.2s}
  .module.done .check{background:var(--accent2);border-color:var(--accent2);color:#04210f}
  .mhead .mt{flex:1}
  .mhead .mt .mtitle{font-weight:600}
  .mhead .mt .mdur{color:var(--muted);font-size:.8rem}
  .chev{color:var(--muted);transition:transform .25s}
  .module.open .chev{transform:rotate(90deg)}
  .mbody{display:none;padding:2px 16px 16px;border-top:1px solid var(--line)}
  .module.open .mbody{display:block;animation:fade .3s ease}
  @keyframes fade{from{opacity:0;transform:translateY(-4px)}to{opacity:1}}
  .mbody h4{margin:18px 0 4px;font-size:.78rem;letter-spacing:1px;text-transform:uppercase;color:var(--accent)}
  .mbody h4.ex{color:var(--blue)}
  .mbody h4.do{color:var(--accent2)}
  .mbody p{margin:6px 0}
  .mbody ul{margin:6px 0;padding-left:20px}
  .mbody code{background:var(--panel2);padding:2px 6px;border-radius:5px;font-size:.9em}
  .callout{background:var(--panel2);border-left:3px solid var(--blue);border-radius:8px;
    padding:10px 14px;margin:8px 0}
  .callout.warn{border-left-color:var(--red)}
  .viz{background:var(--panel2);border:1px solid var(--line);border-radius:10px;padding:10px;margin:8px 0}
  .viz svg{display:block;width:100%;height:auto}
  .viz figcaption{color:var(--muted);font-size:.8rem;margin-top:6px;text-align:center}
  .calc{background:var(--panel2);border:1px solid var(--line);border-radius:10px;padding:14px 16px;margin:10px 0}
  .calc-row{display:flex;align-items:center;justify-content:space-between;gap:12px;margin:7px 0}
  .calc-row label{font-size:.9rem;color:var(--text)}
  .calc-row select,.calc-row input{width:140px;background:var(--panel);color:var(--text);border:1px solid var(--line);
    border-radius:8px;padding:7px 10px;font-size:.92rem}
  .calc-out{margin-top:12px;padding:11px 13px;border-radius:8px;background:rgba(247,147,26,.10);
    border:1px solid var(--accent);font-size:.92rem;line-height:1.5}
  .calc-out b{color:var(--accent)}
  .calc .muted{color:var(--muted)}
  .lesson-link{display:inline-flex;align-items:center;gap:8px;margin:10px 0 2px;color:var(--blue);text-decoration:none;
 border:1px solid var(--line);background:var(--panel2);border-radius:9px;padding:7px 10px;font-size:.9rem;font-weight:600}
 .lesson-link:hover{border-color:var(--accent);color:var(--accent)}
 .lesson-link small{color:var(--muted);font-weight:500}
 .quiz{background:var(--panel2);border:1px solid var(--line);border-radius:10px;padding:14px 16px;margin:16px 0 4px}
  .quiz .q{font-weight:600;margin-bottom:8px}
  .quiz button{display:block;width:100%;text-align:left;background:var(--panel);color:var(--text);
    border:1px solid var(--line);border-radius:8px;padding:9px 12px;margin:6px 0;cursor:pointer;font-size:.95rem}
  .quiz button:hover{border-color:var(--muted)}
  .quiz button.correct{background:rgba(63,185,80,.15);border-color:var(--accent2)}
  .quiz button.wrong{background:rgba(248,81,73,.12);border-color:var(--red)}
  .quiz .fb{margin-top:8px;font-size:.9rem;color:var(--muted);display:none}
  .lvlbadge{display:inline-block;font-size:.66rem;font-weight:700;letter-spacing:.4px;
    text-transform:uppercase;color:var(--bc);border:1px solid var(--bc);border-radius:5px;
    padding:1px 6px;margin-left:8px;vertical-align:middle}
  .disclaimer{background:rgba(248,81,73,.08);border:1px solid rgba(248,81,73,.3);border-radius:var(--radius);
    padding:10px 14px;margin:12px 0;font-size:.86rem;color:var(--muted)}
  .glossary summary{cursor:pointer;font-weight:600;font-size:1.05rem}
  .glossary{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:16px 18px;margin-top:30px}
  .glossary dt{font-weight:600;color:var(--accent);margin-top:10px}

  /* ---------- Account / sign-in modal (Suite SSO) ---------- */
  .small{font-size:.82rem;color:var(--muted)}
  .acct-btn{display:inline-flex;align-items:center;gap:6px;max-width:160px;border:1px solid var(--accent);
    background:transparent;color:var(--accent);padding:5px 10px;border-radius:8px;cursor:pointer;
    font-size:.78rem;font-weight:700;white-space:nowrap}
  .acct-btn:hover{background:rgba(127,127,127,.12)}
  .acct-name{max-width:90px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
  .acct-avatar-fallback{display:inline-flex;align-items:center;justify-content:center;width:20px;height:20px;
    border-radius:50%;flex-shrink:0;background:var(--accent);color:#0b0e14;font-size:11px;font-weight:700}
  .acct-avatar-lg{width:48px;height:48px;font-size:20px}
  .acct-card{display:flex;align-items:center;gap:12px;margin-bottom:12px}
  .acct-card-name{font-weight:700;font-size:15px;color:var(--text)}

  .modal-backdrop{position:fixed;inset:0;background:rgba(0,0,0,.6);z-index:9990;display:none;
    align-items:center;justify-content:center;padding:18px}
  .modal{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);
    box-shadow:0 24px 80px rgba(0,0,0,.55);overflow:hidden}
  .modal-header{padding:16px 18px;border-bottom:1px solid var(--line);display:flex;
    justify-content:space-between;align-items:center;gap:12px}
  .modal-title{font-size:16px;font-weight:700;color:var(--text)}
  .modal-body{padding:18px}
  .modal-footer{padding:16px 18px;border-top:1px solid var(--line);display:flex;
    justify-content:flex-end;gap:10px;flex-wrap:wrap}
  .modal button{border:1px solid var(--line);background:var(--panel2);color:var(--text);
    padding:7px 12px;border-radius:8px;cursor:pointer;font-size:13px;font-weight:600;font-family:inherit}
  .modal button:hover{background:var(--line)}
  .modal button:disabled{opacity:.6;cursor:default}
  .modal button.primary{background:var(--accent);border-color:var(--accent);color:#0b0e14}
  .modal button.danger{background:rgba(248,81,73,.12);border-color:rgba(248,81,73,.35);color:var(--red)}
  .auth-field{display:flex;flex-direction:column;gap:4px;font-size:12px;color:var(--muted);margin-bottom:10px}
  .auth-field input{color:var(--text);background:var(--panel2);border:1px solid var(--line);
    border-radius:6px;padding:7px 9px;font-size:13px;font-family:inherit}
  .auth-err{color:var(--red);font-size:11px;min-height:14px;margin-bottom:10px}
  .totp-secret{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:15px;letter-spacing:.08em;
    background:var(--panel2);border:1px solid var(--line);border-radius:6px;padding:10px;
    text-align:center;margin:10px 0;word-break:break-all}
  .totp-qr{display:flex;justify-content:center;background:#fff;border-radius:8px;padding:12px;margin:10px 0}
  .totp-qr img{display:block;width:176px;height:176px}
  .glossary dd{margin:2px 0 0;color:var(--muted)}