:root{--color-bg:#f5f6fa;--color-surface:#fff;--color-text:#1f2430;--color-muted:#6b7280;--color-border:#e1e4e8;--color-primary:#2952e3;--color-primary-hover:#1f3fc0;--color-correct:#1f9d55;--color-correct-bg:#e6f7ed;--color-incorrect:#d23f3f;--color-incorrect-bg:#fbe9e9;--color-pending-bg:#eef0f5;--color-progress-bg:#fff4dd;--color-progress-text:#9a6700;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;font-family:Segoe UI,system-ui,-apple-system,sans-serif}*{box-sizing:border-box}body{background:var(--color-bg);color:var(--color-text);margin:0;line-height:1.5}#root{max-width:960px;margin:0 auto;padding:1.5rem 1rem 4rem}h1,h2,h3{line-height:1.25}button{cursor:pointer;font-family:inherit}.app-header{justify-content:space-between;align-items:baseline;gap:1rem;margin-bottom:1.5rem;display:flex}.app-header h1{margin:0;font-size:1.5rem}.app-header .tagline{color:var(--color-muted);font-size:.95rem}.app-title{color:inherit;text-decoration:none}.btn{background:var(--color-primary);color:#fff;border:none;border-radius:8px;justify-content:center;align-items:center;padding:.65rem 1.25rem;font-size:1rem;font-weight:600;transition:background-color .15s;display:inline-flex}.btn:hover{background:var(--color-primary-hover)}.btn:disabled{background:var(--color-border);color:var(--color-muted);cursor:not-allowed}.btn-secondary{background:var(--color-surface);color:var(--color-primary);border:1px solid var(--color-primary)}.btn-secondary:hover{background:var(--color-pending-bg)}.card{background:var(--color-surface);border:1px solid var(--color-border);border-radius:12px;padding:1.25rem 1.5rem}.error-text{color:var(--color-incorrect)}.dashboard-summary{justify-content:space-between;align-items:center;gap:1rem;margin-bottom:1.5rem;display:flex}.dashboard-summary h2{margin:0 0 .25rem}.dashboard-summary p{color:var(--color-muted);margin:0}.day-grid{grid-template-columns:repeat(auto-fill,minmax(120px,1fr));gap:.75rem;display:grid}.day-cell{background:var(--color-surface);border:1px solid var(--color-border);color:var(--color-text);border-radius:10px;flex-direction:column;gap:.25rem;padding:.75rem;text-decoration:none;transition:border-color .15s,transform .1s;display:flex}.day-cell:hover{border-color:var(--color-primary);transform:translateY(-1px)}.day-cell__number{font-weight:700}.day-cell__status{color:var(--color-muted);font-size:.85rem}.day-cell__score{font-size:.85rem;font-weight:600}.day-cell--not_started{background:var(--color-pending-bg)}.day-cell--in_progress{background:var(--color-progress-bg)}.day-cell--in_progress .day-cell__status{color:var(--color-progress-text)}.day-cell--completed{background:var(--color-correct-bg)}.day-cell--completed .day-cell__score{color:var(--color-correct)}.day-cell--next{border-color:var(--color-primary);box-shadow:0 0 0 1px var(--color-primary)}.question-view__meta{justify-content:space-between;align-items:center;margin-bottom:.75rem;display:flex}.topic-badge{background:var(--color-pending-bg);color:var(--color-primary);border-radius:999px;padding:.2rem .6rem;font-size:.8rem;font-weight:600;display:inline-block}.question-progress{color:var(--color-muted);font-size:.85rem}.question-text{margin:0 0 1rem;font-size:1.15rem;font-weight:500}.hint-toggle{margin-bottom:.75rem}.hint-box{background:var(--color-progress-bg);border:1px solid var(--color-progress-text);border-radius:8px;margin-bottom:1rem;padding:.75rem 1rem}.choice-list{flex-direction:column;gap:.6rem;margin-bottom:1rem;display:flex}.choice-btn{text-align:left;border:1px solid var(--color-border);background:var(--color-surface);border-radius:8px;align-items:flex-start;gap:.75rem;padding:.75rem 1rem;font-size:1rem;transition:border-color .15s,background-color .15s;display:flex}.choice-btn:not(:disabled):hover{border-color:var(--color-primary)}.choice-btn:disabled{cursor:default}.choice-letter{min-width:1.5rem;font-weight:700}.choice-btn--correct{border-color:var(--color-correct);background:var(--color-correct-bg);color:var(--color-correct)}.choice-btn--incorrect{border-color:var(--color-incorrect);background:var(--color-incorrect-bg);color:var(--color-incorrect)}.choice-btn--muted{opacity:.6}.result{margin:0 0 1rem;font-weight:700}.result--correct{color:var(--color-correct)}.result--incorrect{color:var(--color-incorrect)}.explanation-panel section{margin-bottom:1rem}.explanation-panel h3{margin:0 0 .35rem;font-size:1rem}.explanation-panel p{color:var(--color-text);margin:0}.step-list{margin:0;padding-left:1.25rem}.step-list li{margin-bottom:.25rem}.next-btn{margin-top:.5rem}.summary-score{font-size:1.1rem}.summary-list{flex-direction:column;gap:.4rem;margin:1rem 0;padding:0;list-style:none;display:flex}.summary-list li{border-radius:6px;justify-content:space-between;gap:1rem;padding:.5rem .75rem;font-size:.9rem;display:flex}.summary-item__topic{color:var(--color-muted)}.summary-item--correct{background:var(--color-correct-bg)}.summary-item--incorrect{background:var(--color-incorrect-bg)}.summary-actions{flex-wrap:wrap;gap:.75rem;display:flex}