:root{--bg:#f4f6fa;--surface:#fff;--surface-2:#eef2f8;--text:#17202e;--muted:#5d6b80;--border:#dbe2ec;--primary:#1f3a5f;--primary-text:#fff;--accent:#f5b942;--accent-text:#3d2b00;--ok:#1e8e5a;--ok-bg:#e5f6ee;--bad:#c0392b;--bad-bg:#fdecea;--radius:14px;--shadow:0 1px 2px #1018280f, 0 4px 16px #1018280f;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light}@media (prefers-color-scheme:dark){:root{--bg:#0f1520;--surface:#18212f;--surface-2:#212c3d;--text:#e8edf5;--muted:#97a3b6;--border:#2c384b;--primary:#5b8fd6;--primary-text:#0b1220;--accent:#f5b942;--ok:#4cc38a;--ok-bg:#12301f;--bad:#ef6b5b;--bad-bg:#3a1a17;--shadow:none;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}}*{box-sizing:border-box}html,body{margin:0}body{background:var(--bg);color:var(--text);-webkit-font-smoothing:antialiased;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;line-height:1.5}h1,h2,h3{margin:0 0 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var(--primary) 0%, var(--bg) 55%)}.login-head{align-items:center;gap:14px;margin-bottom:16px;display:flex}.stack{flex-direction:column;gap:16px;display:flex}.stack-sm{flex-direction:column;gap:10px;display:flex}.row{align-items:center;display:flex}.row.between{justify-content:space-between;gap:8px}.row.gap{gap:10px}.row.center{justify-content:center}.wrap{flex-wrap:wrap}.grid{grid-template-columns:repeat(auto-fit,minmax(170px,1fr));gap:12px;display:grid}.grid.two{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}.muted{color:var(--muted)}.small{font-size:.85rem}.eyebrow{text-transform:uppercase;letter-spacing:.06em;color:var(--muted);margin-bottom:4px;font-size:.75rem;font-weight:700}.btn{border:1px solid var(--border);background:var(--surface-2);color:var(--text);font:inherit;cursor:pointer;border-radius:10px;justify-content:center;align-items:center;gap:6px;padding:10px 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var(--border);background:var(--surface);color:var(--text);font:inherit;cursor:pointer;border-radius:10px;padding:12px 14px}.option:hover:not(:disabled){border-color:var(--primary);background:var(--surface-2)}.chips{flex-wrap:wrap;gap:8px;display:flex}.chip{border:1px solid var(--border);background:var(--surface-2);color:var(--text);font:inherit;cursor:pointer;border-radius:999px;padding:8px 12px}.chip:disabled{opacity:.35;cursor:default}.answer-line{border:2px dashed var(--border);border-radius:10px;min-height:48px;padding:12px;font-size:1.1rem}.feedback{border-radius:10px;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:12px;margin-top:16px;padding:14px;display:flex}.feedback p{flex:200px;margin:0}.feedback.ok{background:var(--ok-bg);color:var(--ok)}.feedback.bad{background:var(--bad-bg);color:var(--bad)}.vocab-list{grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:8px;margin-bottom:20px;padding:0;list-style:none;display:grid}.vocab-list li{background:var(--surface-2);border-radius:10px;flex-direction:column;gap:2px;padding:10px 12px;display:flex}.level-badge{background:var(--primary);width:96px;height:96px;color:var(--accent);border-radius:50%;place-items:center;margin:8px auto 12px;font-size:1.8rem;font-weight:800;display:inline-grid}.xp-gain{color:var(--ok);font-size:1.3rem;font-weight:800}.flashcard{border-radius:var(--radius);background:var(--surface-2);cursor:pointer;flex-direction:column;justify-content:center;gap:8px;min-height:180px;margin:16px 0;padding:32px 16px;display:flex}.flashcard h2{margin:0;font-size:1.6rem}.meaning{font-size:1.2rem;font-weight:600}.chat{flex-direction:column;gap:10px;min-height:calc(100vh - 140px);display:flex}.messages{flex-direction:column;flex:1;gap:10px;padding:8px 0;display:flex;overflow-y:auto}.bubble{white-space:pre-wrap;word-wrap:break-word;border-radius:14px;max-width:85%;padding:10px 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