.history-container {
        font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        line-height: 1.6;
        color: #333;
        max-width: 900px;
        margin: 0 auto;
        padding: 20px;
    }
    .history-header {
        text-align: center;
        border-bottom: 2px solid #e67e22;
        padding-bottom: 10px;
        margin-bottom: 30px;
    }
    .history-header h1 {
        color: #2c3e50;
        font-size: 28px;
    }
    .milestone-section {
        margin-bottom: 40px;
        position: relative;
        padding-left: 20px;
        border-left: 3px solid #f1f1f1;
    }
    .milestone-section:hover {
        border-left-color: #e67e22;
    }
    .year-title {
        font-weight: bold;
        color: #e67e22;
        font-size: 1.2em;
        margin-bottom: 10px;
        display: block;
    }
    .milestone-content h3 {
        margin-top: 0;
        color: #2c3e50;
    }
    .highlight-keyword {
        font-weight: 600;
        color: #1a1a1a;
    }
    .product-tags {
        margin-top: 10px;
        font-style: italic;
        color: #7f8c8d;
        font-size: 0.9em;
    }
    ul {
        padding-left: 20px;
    }
    li {
        margin-bottom: 8px;
    }