*{margin:0;padding:0;box-sizing:border-box}:root{--primary-color: #2563eb;--secondary-color: #3b82f6;--accent-color: #60a5fa;--bg-light: #f8fafc;--bg-card: #ffffff;--text-primary: #1e293b;--text-secondary: #64748b;--border-color: #e2e8f0;--success-color: #10b981;--warning-color: #f59e0b;--shadow: 0 4px 6px -1px rgba(0, 0, 0, .1), 0 2px 4px -1px rgba(0, 0, 0, .06);--shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, .1), 0 4px 6px -2px rgba(0, 0, 0, .05)}@media (prefers-color-scheme: dark){:root{--bg-light: #0f172a;--bg-card: #1e293b;--text-primary: #f1f5f9;--text-secondary: #94a3b8;--border-color: #334155}}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,sans-serif;min-height:100vh;background:var(--bg-light);color:var(--text-primary);line-height:1.6}.app-container{max-width:1200px;margin:0 auto;padding:2rem 1rem}.header{text-align:center;margin-bottom:3rem;padding:2rem 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0;box-shadow:var(--shadow)}.btn:hover{background:var(--secondary-color);transform:translateY(-2px);box-shadow:var(--shadow-lg)}.btn:active{transform:translateY(0)}.result{margin-top:1.5rem;padding:1.5rem;background:var(--bg-light);border-radius:8px;font-size:1.125rem;font-weight:600;color:var(--success-color);display:none;animation:slideIn .4s ease}.result.show{display:block}@keyframes slideIn{0%{opacity:0;transform:translate(-20px)}to{opacity:1;transform:translate(0)}}.function-diagram{display:flex;justify-content:space-around;align-items:center;padding:2rem;gap:2rem;flex-wrap:wrap}.set-box{background:var(--bg-light);border:2px solid var(--primary-color);border-radius:12px;padding:1.5rem;min-width:150px;text-align:center}.set-box h4{margin-bottom:1rem;color:var(--primary-color);font-size:1.125rem}.element{background:#fff;border:1px solid var(--border-color);padding:.75rem;margin:.5rem 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1rem;font-size:.875rem}.card{padding:1.5rem}.function-diagram{flex-direction:column}.arrows{transform:rotate(90deg)}}::-webkit-scrollbar{width:10px}::-webkit-scrollbar-track{background:var(--bg-light)}::-webkit-scrollbar-thumb{background:var(--primary-color);border-radius:5px}::-webkit-scrollbar-thumb:hover{background:var(--secondary-color)}*{scrollbar-width:thin;scrollbar-color:var(--primary-color) var(--bg-light)}