.history-section {
            background: #ffffff;
            padding: 3rem 2.5rem;
            margin: 2rem 0;
            border: 2px solid var(--color-border);
        }

        .timeline {
            list-style: none;
            padding: 0;
            position: relative;
            margin: 2rem 0 0 1.5rem;
        }

        .timeline::before {
            content: '';
            position: absolute;
            left: 0;
            top: 0;
            bottom: 0;
            width: 3px;
            background: var(--color-accent);
        }

        .timeline-item {
            position: relative;
            padding: 1rem 0 1rem 2.5rem;
            margin-bottom: 1.5rem;
        }

        .timeline-item::before {
            content: '';
            position: absolute;
            left: -0.5rem;
            top: 1.2rem;
            width: 12px;
            height: 12px;
            background: var(--color-highlight);
            border: 3px solid #ffffff;
        }

        .timeline-year {
            font-family: var(--font-accent);
            font-weight: 700;
            letter-spacing: 0.18em;
            text-transform: uppercase;
            font-size: 0.9rem;
            color: #1a1a1a;
            margin-bottom: 0.5rem;
        }

        .timeline-content {
            background: #f8fafc;
            padding: 1rem 1.5rem;
            border: 2px solid var(--color-border);
            font-weight: 600;
            color: #1a1a1a !important;
            line-height: 1.7;
        }

        .timeline-content ul {
            list-style: none;
            padding: 0;
            margin: 0.5rem 0 0 0;
        }

        .timeline-content li {
            padding: 0.3rem 0;
            color: #1a1a1a !important;
        }

        .timeline-content li::before {
            content: '・';
            color: var(--color-accent);
            font-weight: 700;
            margin-right: 0.3rem;
        }