:root{--bg:#f7f7f5;--surface:#fff;--text:#1d1d1b;--muted:#5f5f5a;--border:#d9d9d4;--accent:#1f5fbf;--accent-text:#fff;--correct:#1e7d3a;--correct-bg:#e5f4e9;--wrong:#b3261e;--wrong-bg:#fbe9e7;--radius:10px;color:var(--text);background:var(--bg);--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;font-size:17px;line-height:1.5}@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--bg:#161615;--surface:#222220;--text:#ececea;--muted:#a8a8a2;--border:#3b3b38;--accent:#6ea2ff;--accent-text:#0d1a33;--correct:#6fcf8a;--correct-bg:#1b3323;--wrong:#ff8a80;--wrong-bg:#3d1f1c;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}}:root[data-theme=dark]{--bg:#161615;--surface:#222220;--text:#ececea;--muted:#a8a8a2;--border:#3b3b38;--accent:#6ea2ff;--accent-text:#0d1a33;--correct:#6fcf8a;--correct-bg:#1b3323;--wrong:#ff8a80;--wrong-bg:#3d1f1c;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}*{box-sizing:border-box}body{background:var(--bg);margin:0}#app{max-width:40rem;margin:0 auto;padding:0 16px 48px}h1,h2,h3{line-height:1.25}h1{margin:1.5rem 0 1rem;font-size:1.5rem}h1:focus,[data-focus]:focus{outline:none}a{color:var(--accent)}img{max-width:100%;height:auto}.muted{color:var(--muted)}.visually-hidden{clip:rect(0 0 0 0);white-space:nowrap;width:1px;height:1px;position:absolute;overflow:hidden}.icon{flex-shrink:0;width:1.2em;height:1.2em}.app-header{border-bottom:1px solid var(--border);align-items:center;gap:12px;padding:12px 0;display:flex}.app-header>:first-child{flex:1;min-width:0}.app-name{font-weight:600}.status-text{color:var(--muted);gap:8px;font-size:.9rem;display:flex}.status-text .topic{text-overflow:ellipsis;white-space:nowrap;color:var(--text);flex:1;overflow:hidden}.progress-bar{background:var(--border);border-radius:2px;height:4px;margin-top:6px;overflow:hidden}.progress-bar span{background:var(--accent);height:100%;transition:width .2s;display:block}button{border:1px solid var(--border);border-radius:var(--radius);background:var(--surface);min-height:44px;color:var(--text);font:inherit;cursor:pointer;justify-content:center;align-items:center;gap:6px;padding:8px 18px;display:inline-flex}button:disabled{opacity:.5;cursor:default}button.primary{border-color:var(--accent);background:var(--accent);color:var(--accent-text);font-weight:600}button.danger{border-color:var(--wrong);color:var(--wrong)}.icon-button{background:0 0;border-color:#0000;min-width:44px;padding:8px}.actions{flex-wrap:wrap;justify-content:flex-end;gap:10px;margin:1.5rem 0;display:flex}.question-body p{margin:.75rem 0}.question-body img{max-height:16rem;margin:0 auto;display:block}.hint{margin:1rem 0 .5rem;font-size:.9rem}.answers{gap:8px;display:grid}.answer{border:1px solid var(--border);border-radius:var(--radius);background:var(--surface);cursor:pointer;align-items:center;gap:12px;padding:12px 14px;display:flex}.answer:has(input:checked){border-color:var(--accent);box-shadow:inset 0 0 0 1px var(--accent)}.answer:has(input:disabled){cursor:default}.answer input{width:1.2em;height:1.2em;accent-color:var(--accent);margin:0}.answer .key{color:var(--muted);min-width:1ch;font-size:.8rem}.answer .text{flex:1}.answer .text p{margin:0}.answer.is-correct{border-color:var(--correct);background:var(--correct-bg);box-shadow:inset 0 0 0 1px var(--correct)}.answer.is-wrong{border-color:var(--wrong);background:var(--wrong-bg);box-shadow:inset 0 0 0 1px var(--wrong)}.answer.is-correct .marker{color:var(--correct)}.answer.is-wrong .marker{color:var(--wrong)}.question-header{align-items:flex-start;gap:8px;display:flex}.question-header h1{flex:1;min-width:0}.suggest{border-radius:var(--radius);width:44px;height:44px;color:var(--muted);justify-content:center;align-items:center;margin-top:calc(1.5rem - 7px);display:inline-flex;position:relative}.suggest:hover{color:var(--accent)}.suggest:after{content:attr(data-tooltip);z-index:2;border:1px solid var(--border);background:var(--surface);width:max-content;max-width:16rem;color:var(--text);pointer-events:none;opacity:0;border-radius:6px;padding:6px 10px;font-size:.85rem;transition:opacity .15s;position:absolute;top:100%;right:0}.suggest:hover:after,.suggest:focus-visible:after{opacity:1}@media (width<=600px){#app:has(.question-actions){padding-bottom:calc(96px + env(safe-area-inset-bottom))}.question-actions{z-index:1;padding:10px 16px calc(10px + env(safe-area-inset-bottom));border-top:1px solid var(--border);background:var(--surface);margin:0;position:fixed;bottom:0;left:0;right:0}.question-actions button{flex:1}}.feedback{border-radius:var(--radius);gap:12px;margin-top:1.25rem;padding:12px 14px;display:flex}.feedback .icon{width:1.5em;height:1.5em}.feedback p{margin:0}.feedback-title{font-weight:600}.feedback.is-correct{background:var(--correct-bg);color:var(--correct)}.feedback.is-wrong{background:var(--wrong-bg);color:var(--wrong)}.feedback.is-wrong p+p{color:var(--text)}.explanation h2{margin:1.5rem 0 .5rem;font-size:1.1rem}.grade{font-size:1.4rem;font-weight:600}.grade.is-correct{color:var(--correct)}.grade.is-wrong{color:var(--wrong)}.level-summary{padding:0;list-style:none}.level-summary li{border-bottom:1px solid var(--border);flex-wrap:wrap;gap:4px 12px;padding:8px 0;display:flex}dialog{border:1px solid var(--border);border-radius:var(--radius);background:var(--surface);width:min(36rem,100vw - 32px);max-height:calc(100vh - 32px);color:var(--text);padding:20px}dialog::backdrop{background:#00000080}.dialog-header{justify-content:space-between;align-items:center;display:flex}.dialog-header h2{margin:0}dialog fieldset{border:0;gap:10px;margin:1rem 0;padding:0;display:grid}dialog legend,dialog h3{margin:1rem 0 .5rem;font-size:1rem;font-weight:600}.mode-option{cursor:pointer;align-items:flex-start;gap:10px;display:flex}.mode-option input{margin-top:.3em}.mode-option>span{display:grid}.mode-option .muted{font-size:.9rem}.links{margin-top:1.5rem;padding-left:1.2rem}dialog.confirm .actions{margin-bottom:0}