/* Reaction Test Area */
        .reaction-test-area {
            text-align: center;
            padding: 2rem;
            border-radius: 8px;
            background-color: var(--light-gray);
            border: 1px solid var(--border-color);
            margin-bottom: 1.5rem;
            transition: all 0.3s;
            min-height: 300px;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            position: relative;
            overflow: hidden;
        }
        
        .reaction-test-area.ready {
            background-color: #d4edda;
            border-color: #28a745;
        }
        
        .reaction-test-area.waiting {
            background-color: #fff3cd;
            border-color: #ffc107;
        }
        
        .reaction-test-area.active {
            background-color: #cce5ff;
            border-color: var(--primary-color);
        }
        
        .reaction-test-area.completed {
            background-color: #d1e7dd;
            border-color: #28a745;
        }
        
        .reaction-test-area h3 {
            font-size: 1.5rem;
            margin-bottom: 1rem;
        }
        
        .reaction-test-area p {
            font-size: 1.1rem;
            margin-bottom: 1.5rem;
        }
        
        .reaction-stats {
            display: flex;
            justify-content: center;
            gap: 2rem;
            margin: 1.5rem 0;
            flex-wrap: wrap;
        }
        
        .stat-box {
            background: white;
            border-radius: 8px;
            padding: 1rem 1.5rem;
            min-width: 120px;
            box-shadow: 0 2px 4px rgba(0,0,0,0.05);
            border: 1px solid var(--border-color);
        }
        
        .stat-value {
            font-size: 2rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 0.25rem;
        }
        
        .stat-label {
            font-size: 0.9rem;
            color: var(--text-muted);
        }
        
        .reaction-result {
            font-size: 2.5rem;
            font-weight: 700;
            color: var(--accent-color);
            margin: 1rem 0;
        }
        
        .reaction-rank {
            font-size: 1.25rem;
            font-weight: 600;
            color: var(--primary-color);
            margin-bottom: 1rem;
        }
        
        .btn-lg {
            padding: 0.75rem 2rem;
            font-size: 1.1rem;
            font-weight: 600;
        }
        
        .btn-success {
            background-color: #28a745;
            border-color: #28a745;
        }
        
        .btn-warning {
            background-color: #ffc107;
            border-color: #ffc107;
            color: #333;
        }
        
        .btn-warning:hover {
            background-color: #e0a800;
            border-color: #d39e00;
        }
        
        .timer-bar {
            height: 8px;
            background-color: #e9ecef;
            border-radius: 4px;
            margin: 1.5rem 0;
            overflow: hidden;
        }
        
        .timer-progress {
            height: 100%;
            background-color: var(--primary-color);
            width: 0%;
            transition: width 0.1s linear;
        }
        
        /* Reaction Area */
        .reaction-area {
            width: 100%;
            height: 300px;
            background-color: #f8f9fa;
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 1.5rem 0;
            cursor: pointer;
            position: relative;
            overflow: hidden;
            border: 2px solid var(--border-color);
            transition: all 0.3s;
        }
        
        .reaction-area.ready {
            background-color: #d4edda;
            border-color: #28a745;
        }
        
        .reaction-area.waiting {
            background-color: #fff3cd;
            border-color: #ffc107;
        }
        
        .reaction-area.active {
            background-color: var(--primary-color);
            border-color: var(--accent-color);
        }
        
        .reaction-area p {
            font-size: 1.2rem;
            font-weight: 600;
            color: white;
            text-align: center;
            margin: 0;
            padding: 1rem;
        }
        
        /* Result Area */
        .result-container {
            background-color: var(--light-gray);
            border-radius: 6px;
            padding: 1.5rem;
            margin-top: 1.5rem;
            position: relative;
            border: 1px solid var(--border-color);
        }
        
        .result-title {
            font-weight: 600;
            margin-bottom: 0.75rem;
            color: var(--primary-color);
        }
        
        .result-content {
            font-family: 'Courier New', monospace;
            word-break: break-all;
            padding: 12px;
            background-color: white;
            border-radius: 4px;
            border: 1px solid #eee;
            font-size: 0.95rem;
        }
        
        .copy-btn {
            position: absolute;
            top: 15px;
            right: 15px;
            background: white;
            border: 1px solid var(--border-color);
            border-radius: 4px;
            padding: 0.4rem 0.75rem;
            cursor: pointer;
            transition: all 0.3s;
        }
        
        .copy-btn:hover {
            background-color: var(--light-gray);
        }
        
        /* Content Sections */
        .section-title {
            font-weight: 600;
            margin-bottom: 1rem;
            color: var(--primary-color);
            padding-bottom: 0.5rem;
            border-bottom: 1px solid var(--border-color);
        }
        
        .usage-step {
            display: flex;
            margin-bottom: 1.5rem;
            align-items: flex-start;
        }
        
        .step-number {
            width: 28px;
            height: 28px;
            background-color: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 1rem;
            flex-shrink: 0;
            font-weight: 600;
            font-size: 0.9rem;
        }
        
        .info-box {
            background-color: rgba(44, 125, 160, 0.05);
            border-left: 3px solid var(--primary-color);
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
        .security-alert {
            background-color: #d4edda;
            border-left: 3px solid #28a745;
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
       
        /* Responsive Adjustments */
        @media (max-width: 768px) {
            .tool-card {
                padding: 1.5rem;
            }
            
            .reaction-stats {
                gap: 1rem;
            }
            
            .stat-box {
                min-width: 100px;
                padding: 0.75rem 1rem;
            }
            
            .stat-value {
                font-size: 1.75rem;
            }
        }
        
         
        /* Reaction History */
        .history-table {
            width: 100%;
            border-collapse: collapse;
            margin: 1.5rem 0;
        }
        
        .history-table th, .history-table td {
            padding: 0.75rem;
            text-align: left;
            border-bottom: 1px solid var(--border-color);
        }
        
        .history-table th {
            background-color: var(--light-gray);
            font-weight: 600;
        }
        
        .history-table tr:hover {
            background-color: rgba(44, 125, 160, 0.05);
        }
        
        .history-table .highlight {
            background-color: rgba(255, 193, 7, 0.2);
            font-weight: 600;
        }
        
        /* Test controls */
        .test-controls {
            display: flex;
            justify-content: center;
            gap: 1rem;
            margin: 1rem 0;
        }
        
        /* Ripple effect */
        .ripple {
            position: absolute;
            border-radius: 50%;
            background-color: rgba(255, 255, 255, 0.7);
            transform: scale(0);
            animation: ripple 0.6s linear;
        }
        
        @keyframes ripple {
            to {
                transform: scale(4);
                opacity: 0;
            }
        }
        
        /* Chart container */
        .chart-container {
            background: white;
            border-radius: 8px;
            padding: 1.5rem;
            margin-top: 1.5rem;
            border: 1px solid var(--border-color);
            height: 300px;
        }
        
        .chart-title {
            font-weight: 600;
            margin-bottom: 1rem;
            color: var(--primary-color);
            padding-bottom: 0.5rem;
            border-bottom: 1px solid var(--border-color);
        }
        
        /* Reaction time levels */
        .reaction-levels {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 1.5rem;
            margin: 2rem 0;
        }
        
        .level-card {
            background: linear-gradient(135deg, rgba(169, 214, 229, 0.2) 0%, rgba(44, 125, 160, 0.2) 100%);
            border-radius: 8px;
            padding: 1.5rem;
            border: 1px solid var(--border-color);
            transition: all 0.3s;
        }
        
        .level-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
        }
        
        .level-title {
            font-weight: 600;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        
        .level-range {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--accent-color);
            margin-bottom: 0.5rem;
        }
        
        .level-desc {
            color: var(--text-muted);
        }