:root {
            --primary-color: #4a6fa5;
            --secondary-color: #166088;
            --accent-color: #4fc3f7;
            --text-color: #333;
            --light-bg: #f8f9fa;
        }
        .timeline-header {
            text-align: center;
            margin-bottom: 40px;
        }

        .timeline-header h1 {
            font-size: 2.5rem;
            color: var(--secondary-color);
            margin-bottom: 10px;
            font-weight: 700;
        }

        .timeline-header p {
            font-size: 1.1rem;
            color: #666;
            max-width: 700px;
            margin: 0 auto;
        }

        .timeline {
            position: relative;
            padding: 40px 0;
        }

        .timeline::before {
            content: '';
            position: absolute;
            width: 4px;
            background-color: var(--accent-color);
            top: 0;
            bottom: 0;
            left: 50%;
            margin-left: -2px;
            border-radius: 2px;
        }

        .timeline-item {
            padding: 20px 40px;
            position: relative;
            width: 50%;
            box-sizing: border-box;
            margin-bottom: 30px;
        }

        .timeline-item:nth-child(odd) {
            left: 0;
        }

        .timeline-item:nth-child(even) {
            left: 50%;
        }

        .timeline-item::after {
            content: '';
            position: absolute;
            width: 20px;
            height: 20px;
            background-color: white;
            border: 4px solid var(--primary-color);
            border-radius: 50%;
            top: 30px;
            z-index: 1;
        }

        .timeline-item:nth-child(odd)::after {
            right: -12px;
        }

        .timeline-item:nth-child(even)::after {
            left: -12px;
        }

        .timeline-content {
            padding: 20px;
            background-color: white;
            border-radius: 8px;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            position: relative;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }

        .timeline-content:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
        }

        .timeline-date {
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 10px;
            display: flex;
            align-items: center;
        }

        .timeline-date .season {
            background-color: var(--accent-color);
            color: white;
            padding: 3px 8px;
            border-radius: 12px;
            font-size: 0.8rem;
            margin-left: 10px;
        }

        .timeline-title {
            font-size: 1.3rem;
            font-weight: 600;
            margin-bottom: 10px;
            color: var(--secondary-color);
        }

        .timeline-desc {
            margin-bottom: 0;
        }

        .timeline-desc::before {
            content: '...';
            color: var(--accent-color);
            font-weight: bold;
            display: inline-block;
            margin-right: 5px;
        }

        @media screen and (max-width: 768px) {
            .timeline-header h1 {
                font-size: 2rem;
            }

            .timeline::before {
                left: 31px;
            }

            .timeline-item {
                width: 100%;
                padding-left: 70px;
                padding-right: 25px;
            }

            .timeline-item:nth-child(even) {
                left: 0;
            }

            .timeline-item::after {
                left: 21px;
            }

            .timeline-item:nth-child(odd)::after,
            .timeline-item:nth-child(even)::after {
                left: 21px;
            }
        }

        .timeline-item {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease-out;
}

.timeline-item.show {
    opacity: 1;
    transform: translateY(0);
}