*,:after,:before{box-sizing:border-box;margin:0;padding:0}:root{--bg:#fff;--bg-secondary:#f5f5f3;--text:#1a1a1a;--text-muted:#888;--border:rgba(0,0,0,.12);--border-hover:rgba(0,0,0,.3);--radius-md:8px;--radius-lg:14px;--green-bg:#e6f4ee;--green-border:#1d9e75;--green-text:#085041;--red-bg:#fce8e8;--red-border:#e24b4a;--red-text:#501313;--amber-bg:#fef3dd;--amber-text:#854f0b;--amber-border:#fac775}@media (prefers-color-scheme:dark){:root{--bg:#111110;--bg-secondary:#1c1c1a;--text:#f0eeea;--text-muted:#666;--border:hsla(0,0%,100%,.1);--border-hover:hsla(0,0%,100%,.3);--green-bg:#0a2018;--green-border:#1d9e75;--green-text:#9fe1cb;--red-bg:#200c0c;--red-border:#e24b4a;--red-text:#f7c1c1;--amber-bg:#1e1200;--amber-text:#fac775;--amber-border:#854f0b}}body{font-family:-apple-system,Hiragino Sans,Hiragino Kaku Gothic ProN,Noto Sans JP,sans-serif;background:var(--bg);color:var(--text);-webkit-font-smoothing:antialiased}.container,body{min-height:100vh}.container{max-width:480px;margin:0 auto;padding:0}.home{padding:2rem 1.25rem 3rem}.logo{font-size:26px;font-weight:600;letter-spacing:-.5px;margin-bottom:4px}.subtitle{font-size:14px;color:var(--text-muted)}.home-logo,.subtitle{margin-bottom:1.5rem}.home-logo img{width:100%;height:auto}.quiz-logo{margin-bottom:1rem}.quiz-logo img{width:48px;height:48px}.section-label{font-size:12px;color:var(--text-muted);margin-bottom:8px}.genre-grid{display:grid;grid-template-columns:repeat(2,1fr);grid-gap:8px;gap:8px;margin-bottom:8px}.genre-card{display:flex;flex-direction:column;gap:4px;background:var(--bg);border:.5px solid var(--border);border-radius:var(--radius-lg);padding:12px 10px;cursor:pointer;text-align:left;transition:border-color .15s}.genre-card:hover{border-color:var(--border-hover)}.genre-card-wide{display:flex;align-items:center;gap:8px;width:100%;background:var(--bg);border:.5px solid var(--border);border-radius:var(--radius-lg);padding:14px 16px;cursor:pointer;text-align:left;transition:border-color .15s;margin-bottom:1.25rem;margin-top:0}.genre-card-wide:hover{border-color:var(--border-hover)}.genre-card-wide.selected{border:1.5px solid var(--text)}.genre-card-wide .genre-name{font-size:15px;font-weight:500;color:var(--text)}.genre-card-wide .genre-icon{font-size:16px;color:var(--text-muted)}.genre-card.selected{border:1.5px solid var(--text)}.genre-icon{font-size:12px;color:var(--text-muted)}.genre-name{font-size:13px;font-weight:500;color:var(--text)}.setting-row{display:flex;align-items:center;gap:12px;margin-bottom:1rem}.setting-label{font-size:13px;color:var(--text-muted);flex:1 1}.setting-value{font-size:13px;font-weight:500;min-width:44px;text-align:right}.setting-row input[type=range]{flex:1.5 1;accent-color:var(--text)}.toggle-row{display:flex;align-items:center;gap:12px;margin-bottom:1.5rem}.toggle{width:40px;height:22px;border-radius:11px;background:var(--border);border:none;cursor:pointer;position:relative;transition:background .2s;flex-shrink:0}.toggle.on{background:var(--text)}.toggle:after{content:"";position:absolute;width:16px;height:16px;border-radius:50%;background:#fff;top:3px;left:3px;transition:left .2s}.toggle.on:after{left:21px}.btn-primary{width:100%;padding:13px;background:var(--text);color:var(--bg);border:none;border-radius:var(--radius-lg);font-size:15px;font-weight:500;cursor:pointer;transition:opacity .15s}.btn-primary:active{opacity:.8}.btn-secondary{width:100%;padding:13px;margin-top:10px;background:transparent;color:var(--text);border:.5px solid var(--border);border-radius:var(--radius-lg);font-size:14px;cursor:pointer}.quiz{padding:1.5rem 1.25rem 3rem}.quiz-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:1.25rem}.quiz-meta{font-size:13px;color:var(--text-muted)}.streak-badge{font-size:13px;font-weight:500;padding:3px 10px;border-radius:var(--radius-md);background:var(--bg-secondary);border:.5px solid var(--border)}.streak-badge.hot{background:var(--amber-bg);color:var(--amber-text);border-color:var(--amber-border)}.timer-bar-wrap{height:3px;background:var(--bg-secondary);border-radius:2px;margin-bottom:1.25rem;overflow:hidden}.timer-bar{height:100%;background:var(--text);border-radius:2px;transition:width .1s linear}.timer-bar.warn{background:var(--red-border)}.diff-row{display:flex;align-items:center;gap:6px;margin-bottom:4px;line-height:1}.diff-badge,.genre-badge{font-size:11px;padding:2px 8px;border-radius:var(--radius-md);background:var(--bg-secondary);color:var(--text-muted);border:.5px solid var(--border)}.diff-badge{display:inline-block;margin-bottom:4px}.question-num{font-size:13px;color:var(--text-muted);margin-bottom:6px}.question-text{font-size:18px;font-weight:500;line-height:1.55;margin-bottom:1.25rem;min-height:56px}.generating{color:var(--text-muted);font-size:15px;font-weight:400}.error-text{color:var(--red-border);font-size:14px;font-weight:400}.choices{display:flex;flex-direction:column;gap:8px;margin-bottom:1rem}.choice-btn{padding:14px 16px;text-align:left;background:var(--bg);border:.5px solid var(--border);border-radius:var(--radius-lg);font-size:14px;color:var(--text);cursor:pointer;transition:border-color .15s;line-height:1.4}.choice-btn:hover:not(:disabled){border-color:var(--border-hover)}.choice-btn:disabled{cursor:default}.choice-btn.correct{border:1.5px solid var(--green-border);background:var(--green-bg);color:var(--green-text)}.choice-btn.wrong{border:1.5px solid var(--red-border);background:var(--red-bg);color:var(--red-text)}.choice-skeleton{height:52px;border-radius:var(--radius-lg);background:var(--bg-secondary);animation:shimmer 1.2s infinite}@keyframes shimmer{0%,to{opacity:.5}50%{opacity:1}}.explanation-box{background:var(--bg-secondary);border-radius:var(--radius-lg);padding:12px 14px;font-size:13px;color:var(--text-muted);line-height:1.65;margin-bottom:1rem}.result{padding:2rem 1.25rem 3rem}.result-center{text-align:center;margin-bottom:2rem}.result-label{font-size:13px;color:var(--text-muted);margin-bottom:4px}.result-score{font-size:56px;font-weight:600;letter-spacing:-2px;margin-bottom:4px}.result-msg{font-size:14px;color:var(--text-muted)}.result-stats{display:grid;grid-template-columns:repeat(3,1fr);grid-gap:8px;gap:8px;margin-bottom:1.5rem}.stat-card{background:var(--bg-secondary);border-radius:var(--radius-md);padding:14px 12px;text-align:center}.stat-num{font-size:24px;font-weight:600}.stat-lbl{font-size:12px;color:var(--text-muted);margin-top:2px}.site-footer{max-width:480px;padding:1.5rem 1.25rem 2rem;border-top:.5px solid var(--border);margin:2rem auto 0}.footer-ads{display:flex;flex-direction:column;gap:10px;margin-bottom:1.25rem}.footer-ad-link{display:block;padding:12px 14px;background:var(--bg-secondary);border:.5px solid var(--border);border-radius:var(--radius-lg);font-size:13px;color:var(--text);text-decoration:none;line-height:1.4;transition:border-color .15s}.footer-ad-link:hover{border-color:var(--border-hover)}.footer-bottom{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:8px}.footer-copy,.footer-counter{font-size:12px;color:var(--text-muted)}