body{margin:0;padding:0;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;line-height:1.6;color:#333}:root{--primary-color:#28a745;--primary-hover:#218838;--background-light:#fff;--background-dark:#121212;--text-light:#000;--text-dark:#fff;--border-light:#e0e0e0;--border-dark:#333}*{box-sizing:border-box;margin:0;padding:0}h1,h2,h3,h4,h5,h6{margin:2rem 0 1rem;line-height:1.2;color:#111}h1{font-size:2.5rem}h2{font-size:2rem}h3{font-size:1.75rem}p{margin:0 0 1.5rem;line-height:1.8}section{margin:2rem 0}.quiz-container{max-width:800px;margin:2rem auto;padding:1rem}.quiz-option{background-color:#fff;color:#333;border:1px solid #e0e0e0;padding:1rem;margin:.5rem 0;border-radius:4px;cursor:pointer;transition:all .2s ease;display:block;width:100%;text-align:left;font-size:1rem}.quiz-option:hover{background-color:#f5f5f5}.button{display:inline-block;padding:12px 24px;background-color:#28a745;color:#fff;text-decoration:none;border-radius:4px;font-weight:500;text-align:center;transition:background-color .2s;cursor:pointer;border:none;font-size:1rem;margin:.5rem}.button:hover{background-color:#218838}a{color:#0070f3;text-decoration:none}a:hover{text-decoration:underline}.math-formula{background-color:#f8f9fa;padding:1.5rem;border-radius:4px;margin:1.5rem 0;overflow-x:auto;border:1px solid #e0e0e0}.score-display{font-size:2rem;text-align:center;margin:2rem 0;font-weight:700}.nav-buttons{display:flex;justify-content:center;gap:1rem;margin:2rem 0;padding-top:1rem;border-top:1px solid #e0e0e0}ol,ul{margin:0 0 1.5rem 2rem}li{margin-bottom:.5rem}code,pre{background-color:#f6f8fa;border-radius:4px;padding:.2em .4em;font-family:monospace}pre{padding:1rem;overflow-x:auto}blockquote,pre{margin:1.5rem 0}blockquote{padding:1rem 1.5rem;border-left:4px solid #e0e0e0;background-color:#f8f9fa;font-style:italic}table{width:100%;border-collapse:collapse;margin:1.5rem 0}td,th{padding:.75rem;border:1px solid #e0e0e0;text-align:left}th{background-color:#f8f9fa;font-weight:600}img{max-width:100%;height:auto;margin:1.5rem 0;border-radius:4px}