:root{color-scheme:dark;--bg: #1a1b1e;--surface: #25262b;--border: #3d3e44;--text: #f1f2f5;--muted: #a0a4ae;--danger: #c94c4c;--ok: #5cb87a;--link: #8ab4ff;font-family:system-ui,Segoe UI,Roboto,Noto Sans JP,sans-serif;background:var(--bg);color:var(--text);line-height:1.5}*{box-sizing:border-box}body{margin:0;min-height:100vh}a{color:var(--link);text-decoration:none}a:hover{text-decoration:underline}.shell{min-height:100vh;display:flex;flex-direction:column}.center{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:2rem 1rem}.narrow{max-width:420px;margin:0 auto;width:100%}.topbar{display:flex;flex-wrap:wrap;align-items:center;gap:.75rem 1rem;padding:.75rem 1.25rem;border-bottom:1px solid var(--border);background:var(--surface)}.brand{font-weight:700;font-size:1.1rem;color:var(--text)}.nav-links{display:flex;flex-wrap:wrap;gap:.75rem 1rem;flex:1}.nav-links a{color:var(--muted)}.nav-links a:hover{color:var(--text)}.topbar-user{display:flex;align-items:center;gap:.75rem}.main{flex:1;padding:1.5rem 1.25rem 3rem;max-width:1100px;margin:0 auto;width:100%}.muted{color:var(--muted);font-size:.95rem}.hero-title{font-size:1.75rem;margin:0 0 .5rem}.hero-sub{margin:0 0 1.5rem;text-align:center}.page-title{font-size:1.5rem;margin:0 0 .5rem}.page-lead{margin:0 0 1.25rem}.card{background:var(--surface);border:1px solid var(--border);border-radius:10px;padding:1.25rem 1.5rem}.form-card{width:100%;max-width:420px}.label{display:flex;flex-direction:column;gap:.35rem;margin-bottom:1rem;font-size:.9rem}.input{padding:.65rem .75rem;border-radius:8px;border:1px solid var(--border);background:#1e1f23;color:var(--text);font-size:1rem}.input:focus{outline:2px solid #4a6fff55;border-color:#4a6fff}.form-error{color:#ff9b9b;margin:0 0 .75rem;font-size:.9rem}.btn{font:inherit;cursor:pointer;border-radius:8px;border:1px solid var(--border);padding:.55rem 1rem;background:#2c2d33;color:var(--text)}.btn:disabled{opacity:.6;cursor:not-allowed}.btn-primary{background:#3d5a9e;border-color:#4a6bc4;color:#fff}.btn-primary:hover:not(:disabled){filter:brightness(1.08)}.btn-ghost{background:transparent;border-color:transparent;color:var(--muted)}.btn-ghost:hover:not(:disabled){color:var(--text)}.btn-block{width:100%}.btn-large{padding:.85rem 1.25rem;font-size:1.1rem}.btn-known{background:#2d5a3d;border-color:#3d7a52;color:#e8fff0;min-width:160px}.btn-unknown{background:#5a2d2d;border-color:#8a4040;color:#ffe8e8;min-width:160px}.menu-grid{display:grid;gap:1rem;grid-template-columns:repeat(auto-fill,minmax(240px,1fr))}.menu-tile{display:flex;flex-direction:column;gap:.35rem;padding:1.25rem;border-radius:10px;border:1px solid var(--border);background:var(--surface);color:inherit;text-align:left;cursor:pointer;font:inherit}.menu-tile:hover{border-color:#5a5d68}.menu-tile-title{font-weight:600;font-size:1.1rem}.category-grid{display:grid;gap:.85rem;grid-template-columns:repeat(auto-fill,minmax(200px,1fr))}.category-card{position:relative;display:flex;flex-direction:column;align-items:flex-start;min-height:100px;padding:1rem;border:none;border-radius:10px;color:#121212;cursor:pointer;font:inherit;text-align:left;box-shadow:inset 0 0 0 1px #0002}.category-card--grey{color:var(--text)}.category-card--grey .category-card-meta{color:var(--muted)}.category-card-title{font-weight:600;font-size:.95rem;padding-right:3.5rem;line-height:1.3}.category-card-meta{margin-top:auto;width:100%;display:flex;justify-content:space-between;align-items:flex-end;gap:.5rem;font-size:.8rem;color:#1a1a1a}.category-card-last{opacity:.85}.category-card-pct{font-weight:700;margin-left:auto}.empty-card{max-width:480px;display:flex;flex-direction:column;gap:1rem;align-items:flex-start}.study-wrap{max-width:640px;margin:0 auto;text-align:center}.session-progress{margin-bottom:1rem}.hiragana-display{font-size:clamp(2.8rem,8vw,4rem);font-weight:600;letter-spacing:.06em;margin:2rem 0 2.5rem;font-family:Noto Sans JP,Hiragino Sans,Yu Gothic,system-ui,sans-serif}.answer-row,.reveal{display:flex;flex-direction:column;align-items:center;gap:1rem}.answer-row{flex-direction:row;flex-wrap:wrap;justify-content:center}.spanish-reveal{font-size:1.35rem;margin:0 0 .5rem;color:#dbe7ff}.hints{font-size:.85rem;width:100%}.summary-stats{list-style:none;padding:0;margin:1rem 0;font-size:1.1rem}.summary-stats li{margin:.5rem 0}.summary-stats .ok{color:#8fd9a8}.summary-stats .bad{color:#ff9b9b}.summary-actions{display:flex;flex-wrap:wrap;gap:.75rem;margin-top:1.25rem}.narrow-inline{max-width:520px}@media (max-width: 640px){.answer-row{flex-direction:column}.btn-known,.btn-unknown{width:100%;max-width:320px}}