:root{font-family:system-ui,Avenir,Helvetica,Arial,sans-serif;line-height:1.5;font-weight:400;color-scheme:light dark;color:#ffffffde;background-color:#242424;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}a{font-weight:500;color:#646cff;text-decoration:inherit}a:hover{color:#535bf2}body{margin:0;display:flex;place-items:center;min-width:320px;min-height:100vh}h1{font-size:3.2em;line-height:1.1}button{border-radius:8px;border:1px solid transparent;padding:.6em 1.2em;font-size:1em;font-weight:500;font-family:inherit;background-color:#1a1a1a;cursor:pointer;transition:border-color .25s}button:hover{border-color:#646cff}button:focus,button:focus-visible{outline:4px auto -webkit-focus-ring-color}@media(prefers-color-scheme:light){:root{color:#213547;background-color:#fff}a:hover{color:#747bff}button{background-color:#f9f9f9}}:root{--primary-color: #4f46e5;--primary-hover: #4338ca;--correct-color: 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h2{margin-bottom:30px;color:var(--text-dark);text-align:center;font-size:1.8rem}.stats-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:20px;margin-bottom:30px}.stat-item{text-align:center;padding:20px;background:var(--bg-light);border-radius:12px;border:2px solid var(--border-color)}.stat-value{font-size:2.5rem;font-weight:700;color:var(--primary-color);margin-bottom:8px}.stat-label{font-size:.95rem;color:var(--text-light);font-weight:500}.stat-hint{font-size:.75rem;color:var(--text-light);margin-top:4px;opacity:.7}.close-modal-btn{width:100%;padding:14px;background:var(--primary-color);color:#fff;border:none;border-radius:12px;font-size:1rem;font-weight:600;cursor:pointer;transition:background .2s ease}.close-modal-btn:hover{background:var(--primary-hover)}.celebration-overlay{position:fixed;inset:0;background:#4f46e5f2;display:flex;align-items:center;justify-content:center;z-index:1000;animation:fadeIn .3s 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.option-button:hover{border-color:var(--primary-color);background:var(--bg-light)}:root.dark-mode .option-button.correct,:root.dark-mode .option-button.selected.correct{border-color:#20c997!important;background:#20c99733!important;color:#6ee7b7!important}:root.dark-mode .option-button.wrong{border-color:#ef4444!important;background:#ef444433!important;color:#fca5a5!important;opacity:.8}:root.dark-mode .option-button.wrong.disabled{border-color:#ef4444!important;background:#ef444433!important;color:#fca5a5!important}:root.dark-mode .result-box{background:var(--card-bg);border-color:var(--border-color)}:root.dark-mode .mode-button{background:var(--card-bg);color:var(--text-dark);border-color:var(--border-color)}:root.dark-mode .mode-button.active{background:var(--primary-color);color:#fff}:root.dark-mode .freq-high{background:#10b98133;color:#6ee7b7}:root.dark-mode .freq-medium{background:#fb923c33;color:#fbbf24}:root.dark-mode .freq-low{background:#ef444433;color:#fca5a5}:root.dark-mode .encouragement-message{background:#ef444426;border-color:#ef44444d;color:#fca5a5}:root.dark-mode .all-options-reveal{background:#4f46e51a;border-color:#4f46e540}:root.dark-mode .reveal-definition{color:#94a3b8}@media(max-width:768px){.header-controls{flex-direction:column;gap:12px;align-items:stretch}.control-buttons{justify-content:center}.icon-button{width:36px;height:36px;font-size:1.1rem}.streak-popup{font-size:1.5rem;padding:15px 30px}.streak-indicator{padding:3px 8px}.streak-icon{width:14px;height:14px}.streak-count{font-size:.8rem}.modal-content{padding:24px;width:95%}.modal-content h2{font-size:1.5rem;margin-bottom:20px}.stats-grid{gap:12px}.stat-item{padding:16px}.stat-value{font-size:2rem}.celebration-content{padding:24px}.celebration-content h2{font-size:2rem}.celebration-score{font-size:1.2rem}.celebration-stats{font-size:1rem}.continue-btn{padding:14px 36px;font-size:1rem}}