:root{--bg-primary: #ffffff;--bg-secondary: #f5f5f5;--bg-card: #ffffff;--text-primary: #333333;--text-secondary: #666666;--border-color: #ddd;--shadow-color: rgba(0,0,0,.1);--success-bg: #e8f5e8;--success-text: #155724;--warning-bg: #fff3cd;--warning-text: #856404;--error-bg: #f8d7da;--error-text: #dc3545;--answer-bg: #f8f9fa;--answer-text: #495057}[data-theme=dark]{--bg-primary: #1a1a1a;--bg-secondary: #2d2d2d;--bg-card: #333333;--text-primary: #ffffff;--text-secondary: #cccccc;--border-color: #555555;--shadow-color: rgba(0,0,0,.3);--success-bg: #1e3a1e;--success-text: #90ee90;--warning-bg: #4a3c28;--warning-text: #ffd700;--error-bg: #4a1a1a;--error-text: #ff6b6b;--answer-bg: #2d2d2d;--answer-text: #e0e0e0}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background-color:var(--bg-secondary);color:var(--text-primary);transition:background-color .3s ease,color .3s ease}.container{max-width:1200px;margin:0 auto;padding:20px}.header{background:var(--bg-card);padding:20px;border-radius:8px;box-shadow:0 2px 8px var(--shadow-color);margin-bottom:20px;display:flex;justify-content:space-between;align-items:center}.header-actions{display:flex;gap:10px;align-items:center}.btn-theme{background:var(--bg-secondary);color:var(--text-primary);border:1px solid var(--border-color);padding:8px 12px;border-radius:4px;cursor:pointer;font-size:16px;transition:all .3s ease}.btn-theme:hover{background:var(--border-color)}.header-content{display:flex;justify-content:center;align-items:center}.login-form{background:var(--bg-card);padding:30px;border-radius:8px;box-shadow:0 2px 8px var(--shadow-color);max-width:400px;margin:0 auto}.form-group{margin-bottom:15px}.form-group label{display:block;margin-bottom:5px;font-weight:700;color:var(--text-primary)}.form-group input{width:100%;padding:8px 12px;border:1px solid var(--border-color);border-radius:4px;font-size:14px;background:var(--bg-primary);color:var(--text-primary)}.btn{padding:10px 20px;border:none;border-radius:4px;cursor:pointer;font-size:14px;transition:background-color .3s}.btn-primary{background-color:#1890ff;color:#fff}.btn-primary:hover{background-color:#40a9ff}.btn-secondary{background-color:var(--bg-secondary);color:var(--text-primary);border:1px solid var(--border-color)}.btn-secondary:hover{background-color:var(--border-color)}.btn-warning{background-color:#faad14;color:#fff}.btn-warning:hover{background-color:#ffc53d}.modules-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:20px;margin-top:20px}.module-card{background:var(--bg-card);padding:20px;border-radius:8px;box-shadow:0 2px 8px var(--shadow-color);cursor:pointer;transition:transform .3s}.module-card:hover{transform:translateY(-2px)}.module-card h3{margin-bottom:10px;color:var(--text-primary)}.module-card p{color:var(--text-secondary);margin-bottom:5px}.question-card{background:var(--bg-card);padding:20px;border-radius:8px;box-shadow:0 2px 8px var(--shadow-color);margin-bottom:20px}.question-content{font-size:18px;font-weight:700;margin-bottom:15px;color:var(--text-primary)}.options{margin:15px 0}.option{padding:10px;margin:5px 0;border:1px solid var(--border-color);border-radius:4px;cursor:pointer;background:var(--bg-primary);color:var(--text-primary)}.option:hover{background-color:var(--bg-secondary)}.option.selected{background-color:#1890ff1a;border-color:#1890ff}.navigation{display:flex;justify-content:space-between;margin-top:20px}.footer{margin-top:20px;display:flex;flex-direction:column;justify-content:center;align-items:center}.loading{text-align:center;padding:20px;color:var(--text-secondary)}.error{background:rgba(255,77,79,.1);border:1px solid rgba(255,77,79,.3);color:#ff4d4f;padding:10px;border-radius:4px;margin-bottom:20px}