:root{--bg: #fafafa;--bg-elev: #ffffff;--bg-sunk: #f3f4f6;--border: #e5e7eb;--border-strong: #d4d4d8;--text: #18181b;--text-soft: #52525b;--text-mute: #a1a1aa;--accent: #18181b;--accent-soft: #404040;--good: #2f6f49;--bad: #9b3232;--warn: #8a6d1a;--shadow: 0 1px 2px rgba(0,0,0,.04), 0 1px 4px rgba(0,0,0,.04);--radius: 10px;--radius-sm: 6px;--transition: .16s ease;--container: 1280px;--mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace}[data-theme=dark]{--bg: #0a0a0a;--bg-elev: #161616;--bg-sunk: #1f1f1f;--border: #2a2a2a;--border-strong: #3a3a3a;--text: #fafafa;--text-soft: #c7c7c7;--text-mute: #777777;--accent: #fafafa;--accent-soft: #d4d4d4;--good: #6fb38a;--bad: #d4767a;--warn: #d8b864;--shadow: 0 1px 2px rgba(0,0,0,.5), 0 1px 4px rgba(0,0,0,.5)}*{box-sizing:border-box}html,body,#root{height:100%;margin:0}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Pretendard,Apple SD Gothic Neo,sans-serif;font-size:15px;line-height:1.55;background:var(--bg);color:var(--text);-webkit-font-smoothing:antialiased;text-size-adjust:100%;-webkit-tap-highlight-color:transparent}a{color:inherit;text-decoration:none}button{font:inherit;cursor:pointer}.shell{min-height:100%;display:flex;flex-direction:column}.header{position:sticky;top:0;z-index:50;background:var(--bg-elev);border-bottom:1px solid var(--border);padding:10px 14px;display:flex;align-items:center;justify-content:space-between;gap:10px}.header h1{font-size:15px;font-weight:600;margin:0;letter-spacing:-.01em}.header-meta{color:var(--text-mute);font-size:12px}.nav{display:flex;gap:4px;overflow-x:auto;border-bottom:1px solid var(--border);background:var(--bg-elev);padding:0 8px}.nav a{padding:10px 12px;font-size:13px;color:var(--text-soft);border-bottom:2px solid transparent;white-space:nowrap}.nav a.active{color:var(--text);border-bottom-color:var(--accent)}.main{flex:1;padding:16px;max-width:var(--container);width:100%;margin:0 auto}.btn{display:inline-flex;align-items:center;gap:6px;padding:8px 12px;border-radius:var(--radius-sm);border:1px solid var(--border-strong);background:var(--bg-elev);color:var(--text);font-size:13px;transition:var(--transition)}.btn:hover{background:var(--bg-sunk)}.btn.primary{background:var(--accent);color:var(--bg-elev);border-color:var(--accent)}.btn.primary:hover{background:var(--accent-soft)}.btn.ghost{border-color:transparent;background:transparent}.btn.ghost:hover{background:var(--bg-sunk)}.btn.sm{padding:5px 9px;font-size:12px}.btn[disabled]{opacity:.5;cursor:not-allowed}.input,.select{width:100%;padding:9px 12px;border:1px solid var(--border-strong);border-radius:var(--radius-sm);background:var(--bg-elev);color:var(--text);font-size:14px}.input:focus,.select:focus{outline:2px solid var(--accent);outline-offset:-2px}.card{background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius);padding:18px}.card+.card{margin-top:12px}.section-title{font-size:13px;font-weight:600;color:var(--text-soft);margin:0 0 10px;display:flex;align-items:center;gap:8px}.section-title .count{color:var(--text-mute);font-weight:400}.progress-bar{height:6px;background:var(--bg-sunk);border-radius:3px;overflow:hidden}.progress-bar>span{display:block;height:100%;background:var(--accent);transition:width .22s ease}.metrics{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:12px}.metric{background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius);padding:14px 16px}.metric .label{font-size:12px;color:var(--text-mute)}.metric .value{font-size:26px;font-weight:600;margin-top:4px;letter-spacing:-.02em}.metric .sub{font-size:11px;color:var(--text-mute);margin-top:2px}.problem-grid{display:grid;gap:12px}.problem-grid.layout-1,.problem-grid.layout-2,.problem-grid.layout-4{grid-template-columns:1fr}@media (min-width: 720px){.problem-grid.layout-2,.problem-grid.layout-4{grid-template-columns:repeat(2,1fr)}}@media (min-width: 1024px){.problem-grid.layout-4{grid-template-columns:repeat(2,1fr)}}.problem{background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius);padding:16px;display:flex;flex-direction:column;gap:10px}.problem.flagged{border-left:3px solid var(--warn)}.problem-head{display:flex;align-items:center;justify-content:space-between;gap:6px;font-size:12px;color:var(--text-mute)}.problem-head .num{font-weight:600;color:var(--text);font-size:13px}.problem-head .subj{background:var(--bg-sunk);padding:2px 8px;border-radius:999px;font-size:11px}.problem-q{font-size:14.5px;line-height:1.6;white-space:pre-wrap}.problem-mock-badge{display:inline-block;font-size:10px;padding:2px 6px;background:var(--bg-sunk);color:var(--text-soft);border-radius:4px;margin-right:6px}.choices{display:flex;flex-direction:column;gap:6px;margin-top:4px}.choice{display:flex;gap:10px;align-items:flex-start;padding:10px 12px;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--bg);text-align:left;font-size:14px;color:var(--text);transition:var(--transition)}.choice:hover{background:var(--bg-sunk)}.choice .label{font-weight:600;color:var(--text-soft);font-size:13px;min-width:18px}.choice.selected{border-color:var(--accent);background:var(--bg-sunk)}.choice.correct{border-color:var(--good);background:#2f6f4912;color:var(--good)}.choice.wrong{border-color:var(--bad);background:#9b323212;color:var(--bad)}.explanation{margin-top:8px;border-top:1px dashed var(--border);padding-top:12px;font-size:13.5px;color:var(--text-soft);white-space:pre-wrap}.explanation .tip{margin-top:8px;padding:8px 10px;background:var(--bg-sunk);border-radius:var(--radius-sm);font-size:12.5px;color:var(--text-soft)}.explanation .label{font-weight:600;color:var(--text);font-size:12px;margin-bottom:4px}.problem-actions{display:flex;gap:6px;flex-wrap:wrap;align-items:center;border-top:1px solid var(--border);padding-top:10px;margin-top:4px}.problem-actions .spacer{flex:1}.pager{position:sticky;bottom:0;background:var(--bg-elev);border-top:1px solid var(--border);padding:10px 14px;display:flex;align-items:center;gap:8px;z-index:40}.pager .progress{flex:1;font-size:12px;color:var(--text-mute);text-align:center}.list-row{display:flex;gap:12px;align-items:center;padding:12px 14px;border:1px solid var(--border);border-radius:var(--radius);background:var(--bg-elev);margin-bottom:8px;transition:var(--transition)}.list-row:hover{border-color:var(--border-strong)}.list-row .summary{flex:1;font-size:13.5px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.list-row .num{min-width:36px;font-weight:600;color:var(--text-soft);font-size:13px}.list-row .meta{font-size:11px;color:var(--text-mute);margin-top:2px;display:flex;gap:6px;flex-wrap:wrap}.dot{width:6px;height:6px;border-radius:50%;display:inline-block}.dot.correct{background:var(--good)}.dot.wrong{background:var(--bad)}.dot.flagged{background:var(--warn)}.card-grid{display:grid;grid-template-columns:1fr;gap:10px}@media (min-width: 600px){.card-grid{grid-template-columns:repeat(2,1fr)}}@media (min-width: 960px){.card-grid{grid-template-columns:repeat(3,1fr)}}.thumb{background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius);padding:14px;cursor:pointer;transition:var(--transition);display:flex;flex-direction:column;gap:6px;min-height:120px}.thumb:hover{border-color:var(--border-strong);transform:translateY(-1px)}.thumb .num{font-weight:600;font-size:13px}.thumb .preview{font-size:13px;color:var(--text-soft);display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}.thumb .row{display:flex;justify-content:space-between;align-items:center;gap:6px}.setting-row{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:12px 0;border-bottom:1px solid var(--border)}.setting-row:last-child{border-bottom:0}.setting-row .label{font-size:14px;font-weight:500}.setting-row .desc{font-size:12px;color:var(--text-mute);margin-top:2px}.toggle{width:38px;height:22px;padding:2px;background:var(--bg-sunk);border-radius:999px;border:1px solid var(--border-strong);position:relative;cursor:pointer;transition:var(--transition)}.toggle.on{background:var(--accent);border-color:var(--accent)}.toggle .knob{width:16px;height:16px;background:var(--bg-elev);border-radius:50%;transition:var(--transition)}.toggle.on .knob{transform:translate(16px)}.search-bar{display:flex;gap:8px;margin-bottom:14px}.search-bar .input{flex:1}.pills{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:12px}.pill{font-size:12px;padding:5px 10px;border:1px solid var(--border-strong);border-radius:999px;background:var(--bg-elev);color:var(--text-soft);cursor:pointer;transition:var(--transition)}.pill.active{background:var(--accent);color:var(--bg-elev);border-color:var(--accent)}.flag-btn{border:none;background:transparent;padding:4px;font-size:16px;color:var(--text-mute)}.flag-btn.on{color:var(--warn)}.photo-viewer{position:fixed;inset:0;z-index:100;background:#000000d9;display:flex;align-items:stretch;justify-content:stretch;padding:0}.photo-viewer-content{flex:1;display:flex;flex-direction:column;background:var(--bg);margin:16px;border-radius:var(--radius);overflow:hidden;box-shadow:0 10px 30px #0006}@media (max-width: 640px){.photo-viewer-content{margin:0;border-radius:0}}.photo-viewer-bar{display:flex;align-items:center;gap:6px;padding:10px 12px;background:var(--bg-elev);border-bottom:1px solid var(--border)}.photo-viewer-stage{flex:1;overflow:auto;display:flex;align-items:center;justify-content:center;background:#0a0a0a;padding:12px}.photo-viewer-stage img{max-width:100%;max-height:100%;transition:transform .16s ease;transform-origin:center;user-select:none;-webkit-user-drag:none}.photo-viewer-foot{display:flex;justify-content:space-between;align-items:center;padding:8px 12px;background:var(--bg-elev);border-top:1px solid var(--border)}.empty{padding:40px 16px;text-align:center;color:var(--text-mute);font-size:13px}
