.group-heading{scroll-margin-top:145px;margin:26px 0 12px;padding:13px 15px;border-radius:16px;background:linear-gradient(110deg,#4b3527,#654936);color:#f6eee7;display:flex;align-items:center;gap:10px;box-shadow:var(--shadow-sm)}
.group-heading.sub{margin-top:18px;background:var(--brand-soft);color:var(--brand);border:1px solid var(--line);box-shadow:none}
.group-heading h3{margin:0;font-size:16px;line-height:1.2;letter-spacing:-.025em}.group-heading span{margin-left:auto;font-size:10.5px;opacity:.78;white-space:nowrap}
.question-card{scroll-margin-top:145px;position:relative;background:var(--surface);border:1px solid var(--line);border-radius:22px;padding:20px;margin-bottom:14px;box-shadow:var(--shadow-xs);transition:border-color .18s var(--ease),box-shadow .18s var(--ease)}
.question-card:hover{border-color:var(--line-strong);box-shadow:var(--shadow-sm)}
.card-top{display:flex;align-items:center;gap:7px;flex-wrap:wrap;padding-bottom:13px;margin-bottom:14px;border-bottom:1px solid var(--line)}
.qnum{min-height:36px;display:inline-flex;align-items:center;text-decoration:none;border-radius:11px;padding:0 12px;background:linear-gradient(135deg,#4b3527,#6b4b37);color:#fff;font-weight:900;font-size:12px;box-shadow:0 5px 12px rgba(55,37,23,.16)}
.qnum:hover{transform:translateY(-1px)}
.crumb{min-width:0;color:var(--muted);font-size:10.5px;line-height:1.35}.badge{margin-left:auto;border-radius:999px;padding:4px 9px;font-size:9px;font-weight:900;text-transform:uppercase;letter-spacing:.04em;background:var(--brand-soft);color:var(--brand)}.badge.flawed{background:var(--warn-bg);color:var(--warn)}.badge.ambiguous{background:var(--violet-bg);color:var(--violet)}.badge.defective{background:var(--red-bg);color:var(--red)}
.prompt{white-space:pre-wrap;margin:0 0 15px;color:var(--ink);font-size:16px;line-height:1.67;font-weight:620}.prompt .katex{font-size:1.07em}.display-math{overflow-x:auto;overflow-y:hidden;-webkit-overflow-scrolling:touch;padding:5px 2px 8px;margin-bottom:8px}.display-math .katex-display{margin:.35em 0}
.source-wrap{position:relative;margin:12px 0 15px;padding:9px;border:1px solid var(--line);border-radius:16px;background:var(--surface-2)}.source-note{display:flex;align-items:center;justify-content:space-between;gap:8px;margin:0 2px 7px;color:var(--muted);font-size:9.5px}.source-image{width:auto;max-width:100%;max-height:min(62dvh,650px);height:auto;margin:auto;border-radius:10px;background:#fff;object-fit:contain;cursor:zoom-in}
.options{display:grid;gap:9px}.option{width:100%;min-height:52px;display:grid;grid-template-columns:34px minmax(0,1fr);align-items:start;gap:11px;text-align:left;border:1.5px solid var(--line);border-radius:15px;background:var(--surface);color:var(--ink);padding:11px 12px;transition:.16s var(--ease)}.option:hover:not(:disabled){border-color:var(--gold);background:color-mix(in srgb,var(--brand-soft) 58%,var(--surface));transform:translateY(-1px)}
.option-letter{width:32px;height:32px;border-radius:10px;display:grid;place-items:center;background:var(--surface-2);border:1px solid var(--line);color:var(--brand);font-weight:950;text-transform:uppercase;font-size:12px}.option>span:last-child{align-self:center;min-width:0;line-height:1.5}.option.selected{border-color:var(--gold);background:var(--brand-soft);box-shadow:0 0 0 3px color-mix(in srgb,var(--gold) 14%,transparent)}.option.selected .option-letter{background:linear-gradient(145deg,var(--gold-soft),var(--gold));border-color:transparent;color:#2f2117}.option.correct{border-color:var(--green-line);background:var(--green-bg)}.option.correct .option-letter{background:var(--green);color:var(--on-green);border-color:transparent}.option.wrong{border-color:var(--red-line);background:var(--red-bg)}.option.wrong .option-letter{background:var(--red);color:var(--on-red);border-color:transparent}.option:disabled{cursor:default;opacity:1}
.card-actions{display:flex;align-items:center;gap:9px;flex-wrap:wrap;margin-top:13px}.verify-btn{min-height:43px;border:0;border-radius:12px;background:linear-gradient(135deg,var(--brand),var(--brand-2));color:var(--on-brand);padding:0 16px;font-weight:900;font-size:12px;box-shadow:0 8px 19px color-mix(in srgb,var(--brand) 22%,transparent);transition:.16s var(--ease)}.verify-btn:hover:not(:disabled){transform:translateY(-1px)}.verify-btn:disabled{background:var(--surface-3);color:var(--muted);box-shadow:none;cursor:not-allowed}.answer-feedback{font-size:12px;font-weight:900}.answer-feedback.ok{color:var(--green)}.answer-feedback.bad{color:var(--red)}
.solution-toggle{width:100%;min-height:44px;margin-top:13px;border:1.5px dashed var(--line-strong);border-radius:13px;background:var(--surface);color:var(--brand);display:flex;align-items:center;gap:9px;padding:0 13px;text-align:left;font-size:11.5px;font-weight:900;transition:.16s var(--ease)}.solution-toggle:hover{border-style:solid;background:var(--brand-soft);border-color:var(--gold)}.solution-toggle svg{width:14px;height:14px;transition:transform .18s var(--ease)}.solution-toggle[aria-expanded="true"] svg{transform:rotate(180deg)}.solution-toggle .hint{margin-left:auto;color:var(--muted);font-size:9.5px;font-weight:700}
.solution-wrap[data-open="false"] .solution{display:none}.solution-wrap[data-open="true"]{animation:solutionIn .22s var(--ease)}@keyframes solutionIn{from{opacity:0;transform:translateY(-4px)}to{opacity:1;transform:none}}
.solution{margin-top:10px;border:1px solid var(--line);border-radius:18px;overflow:hidden;background:var(--surface)}.solution-head{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:11px 14px;background:linear-gradient(120deg,var(--brand-soft),var(--surface-2));color:var(--brand);font-size:12px;font-weight:950}.solution-head small{color:var(--muted);font-size:9.5px}.solution-body{padding:14px}
.correct-line,.issue-line,.coach-line{padding:10px 12px;border-radius:0 11px 11px 0;margin-bottom:12px;font-size:12px}.correct-line{border-left:4px solid var(--green);background:var(--green-bg)}.issue-line{border-left:4px solid var(--gold);background:var(--warn-bg);color:var(--warn)}.coach-line{border-left:4px solid var(--brand);background:var(--brand-soft);color:var(--ink-2)}
.solution-section{padding-top:12px;margin-top:12px;border-top:1px solid var(--line)}.solution-section:first-of-type{padding-top:0;margin-top:0;border-top:0}.solution-section h4{display:flex;align-items:center;gap:8px;margin:0 0 7px;color:var(--brand);font-size:10px;font-weight:950;text-transform:uppercase;letter-spacing:.08em}.solution-section h4 span{width:22px;height:22px;border-radius:8px;display:grid;place-items:center;background:var(--brand-soft);font-size:9px}.solution-section p{margin:0;color:var(--ink-2);font-size:12.3px;line-height:1.62}.steps{margin:0;padding-left:21px}.steps li{margin:6px 0;color:var(--ink-2);font-size:12.3px;line-height:1.58}.steps li::marker{color:var(--brand);font-weight:900}
.option-analysis{display:grid;gap:6px}.analysis-row{display:grid;grid-template-columns:28px minmax(0,1fr);gap:8px;align-items:start;padding:8px 9px;border-radius:11px;background:var(--surface-2);border:1px solid transparent;font-size:11.5px;line-height:1.52}.analysis-row b{text-transform:uppercase;color:var(--brand)}.analysis-row.good{background:var(--green-bg);border-color:var(--green-line)}.analysis-row.good b{color:var(--green)}
.memory-chip{display:inline-flex;align-items:center;gap:7px;margin-top:9px;padding:7px 10px;border-radius:999px;background:var(--surface-2);border:1px solid var(--line);color:var(--muted);font-size:10px;font-weight:750}
.load-more{display:block;min-height:46px;margin:22px auto;border:0;border-radius:14px;background:linear-gradient(135deg,#4b3527,#684a37);color:#fff;padding:0 18px;font-weight:900;font-size:12px;box-shadow:var(--shadow-sm);transition:.18s var(--ease)}.load-more:hover{transform:translateY(-1px)}.empty{padding:36px 18px;text-align:center;border:1.5px dashed var(--line-strong);border-radius:18px;background:var(--surface);color:var(--muted)}
.pdf-jump{white-space:nowrap}