*{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:#f5f5f5}#root{min-height:100vh}:root{--primary: #3a2d7f;--secondary: #10b981;--danger: #ef4444;--light-gray: #f9fafb;--gray: #e5e7eb;--dark-gray: #6b7280}.container{max-width:1200px;margin:0 auto;padding:0 20px}.btn{padding:12px 24px;border:none;border-radius:8px;font-size:16px;cursor:pointer;transition:all .3s ease;font-weight:600}.btn-primary{background-color:var(--primary);color:#fff}.btn-primary:hover{background-color:#2f2569}.btn-secondary{background-color:var(--secondary);color:#fff}.btn-secondary:hover{background-color:#059669}.btn-disabled{background-color:var(--gray);color:var(--dark-gray);cursor:not-allowed}.text-center{text-align:center}.mt-20{margin-top:20px}.mt-30{margin-top:30px}.mb-20{margin-bottom:20px}.p-20{padding:20px}.card{background:white;border-radius:12px;box-shadow:0 2px 8px #0000001a;padding:30px}.header{background-color:var(--primary);color:#fff;padding:20px 0;display:flex;justify-content:space-between;align-items:center}.header h1{font-size:28px}.header .login-btn{background-color:#fff;color:var(--primary);padding:10px 20px;border-radius:8px;font-weight:600;cursor:pointer}input,textarea{width:100%;padding:12px;margin-bottom:15px;border:1px solid var(--gray);border-radius:8px;font-size:16px}input:focus,textarea:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px #3a2d7f1a}input[type=radio],input[type=checkbox]{width:auto;margin-right:10px;margin-bottom:0;cursor:pointer}.leaderboard-table{width:100%;border-collapse:collapse}.leaderboard-table th,.leaderboard-table td{padding:15px;text-align:left;border-bottom:1px solid var(--gray)}.leaderboard-table th{background-color:var(--light-gray);font-weight:600;color:var(--primary)}.leaderboard-table tr:hover{background-color:var(--light-gray)}.timer{display:flex;align-items:center;gap:10px;font-size:18px;font-weight:600}.timer.warning{color:#ef4444}.spinner{border:4px solid var(--gray);border-top:4px solid var(--primary);border-radius:50%;width:40px;height:40px;animation:spin 1s linear infinite;margin:20px auto}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.error-message{background-color:#fee;color:#c00;padding:15px;border-radius:8px;margin-bottom:20px;border-left:4px solid #c00}.success-message{background-color:#efe;color:#0a0;padding:15px;border-radius:8px;margin-bottom:20px;border-left:4px solid #0a0}@media (max-width: 768px){.container{padding:0 10px}.card{padding:20px}.header{flex-direction:column;gap:15px}.header h1{font-size:24px}}