:root{--bg:#f3f6f8;--phone:#ffffff;--text:#111827;--muted:#6b7280;--line:#e5e7eb;--soft:#f5f7fa;--blue:#08a9ee;--blue-dark:#047db4;--blue-soft:#dcf7ff;--red:#f05252;--red-soft:#ffe5e5;--green:#18b87a;--green-soft:#ddf8ee;--yellow:#d89a00;--yellow-soft:#fff3bf;--shadow:0 16px 40px rgba(15,23,42,0.12)}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}body,html{width:100%;height:100%;margin:0;overflow:hidden;overscroll-behavior:none;background:var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Hiragino Sans GB,Microsoft YaHei,sans-serif}button,input{font:inherit}button{cursor:pointer;-webkit-tap-highlight-color:transparent;touch-action:manipulation}button:focus{outline:none}button:focus-visible{outline:2px solid rgba(8,169,238,.42);outline-offset:2px}a{color:inherit;text-decoration:none}.phone-shell{position:relative;width:100vw;height:100svh;margin:0 auto;background:var(--phone);overflow:hidden}@media (orientation:landscape) and (max-width:899px){.phone-shell{width:calc((100svh - 24px) * 3 / 4);height:calc(100svh - 24px);margin:12px auto;aspect-ratio:3/4;box-shadow:var(--shadow)}}@media (min-width:900px){body{min-height:100vh;display:grid;place-items:center}.phone-shell{width:calc((100vh - 24px) * 3 / 4);min-height:auto;height:calc(100vh - 24px);aspect-ratio:3/4;border-radius:28px;box-shadow:var(--shadow)}}.screen{height:100%;min-height:0;display:flex;flex-direction:column;background:#fff;overflow:hidden}@media (min-width:900px){.screen{height:100%}}.topbar{height:60px;padding:12px 18px;justify-content:space-between;flex:0 0 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p{margin:0;color:var(--muted);font-size:14px;line-height:1.5}.pill-row{display:flex;gap:8px;flex-wrap:wrap;margin-top:16px}.pill{border:1px solid var(--line);background:#fff;border-radius:999px;padding:9px 13px;font-weight:700}.pill.active{background:var(--blue);color:#fff;border-color:var(--blue)}.question-wrap{padding:18px 18px 96px;flex:1 1 auto;min-height:0;overflow:auto;overscroll-behavior:contain;-webkit-overflow-scrolling:touch;touch-action:pan-y;-webkit-user-select:none;-moz-user-select:none;user-select:none}.question-panel{will-change:transform,opacity}.question-panel.slide-next{animation:slide-next-in .22s ease-out both}.question-panel.slide-prev{animation:slide-prev-in .22s ease-out both}@keyframes slide-next-in{0%{opacity:0;transform:translateX(18px)}to{opacity:1;transform:translateX(0)}}@keyframes slide-prev-in{0%{opacity:0;transform:translateX(-18px)}to{opacity:1;transform:translateX(0)}}.question-meta{display:flex;align-items:center;gap:8px;color:var(--muted);font-size:14px;margin-bottom:8px;padding-bottom:2px}.type-badge{background:var(--blue);color:#fff;border-radius:5px;padding:4px 7px;font-size:13px;font-weight:800}.question-title{margin:0 0 22px;font-size:25px;line-height:1.48;font-weight:800}.option-list{display:grid;grid-gap:14px;gap:14px}.option{width:100%;border:1px solid transparent;background:#fff;display:grid;grid-template-columns:44px 1fr;grid-gap:13px;gap:13px;align-items:center;padding:10px 4px;text-align:left}.option-letter{width:40px;height:40px;border-radius:50%;display:grid;place-items:center;border:1px solid var(--line);box-shadow:0 3px 10px rgba(15,23,42,.08);color:#374151;font-weight:800}.option-text{font-size:22px;line-height:1.35;color:#2d3748}.option.selected .option-letter{background:var(--blue);color:#fff;border-color:var(--blue)}.option.correct 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solid var(--line)}.sheet-grid{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;padding-top:18px}@media (min-aspect-ratio:16/11),(min-width:700px),(orientation:landscape){.sheet{max-height:calc(100% - 24px)}}.number-dot{flex:0 0 52px;border:1px solid var(--line);background:#fff;color:#8b95a1;width:52px;height:52px;border-radius:50%;font-weight:800}.number-dot.done{background:var(--green-soft);color:var(--green);border-color:transparent}.number-dot.wrong{background:var(--red-soft);color:var(--red);border-color:transparent}.number-dot.current{border:2px solid var(--blue);color:var(--blue);background:var(--blue-soft)}.explain{margin-top:22px;padding:16px;background:#f8fafc;border:1px solid var(--line);border-radius:8px}.explain h3{margin:0 0 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solid var(--line);padding:6px 8px;text-align:left}.admin-panel,.auth-form{display:grid;grid-gap:12px;gap:12px}.field{display:grid;grid-gap:7px;gap:7px}.field span{font-weight:800;font-size:14px}.input{width:100%;border:1px solid var(--line);min-height:46px;padding:0 12px;background:#fff}.input,.tabs{border-radius:8px}.tabs{display:grid;grid-template-columns:1fr 1fr;grid-gap:8px;gap:8px;padding:4px;background:var(--soft)}.tab{border:0;border-radius:7px;min-height:40px;background:transparent;font-weight:900}.tab.active{background:#fff;box-shadow:0 3px 10px rgba(15,23,42,.08)}.row{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:12px 0;border-bottom:1px solid var(--line)}.notice{border-radius:8px;padding:12px;background:var(--blue-soft);color:var(--blue-dark);line-height:1.5}.error{background:var(--red-soft);color:var(--red)}