/* 时间线模块 */
.section-timeline {
    padding: 5rem 0;
    background: #f8fafc;
}

.timeline {
    position: relative;
    max-width: 960px;
    margin: 0 auto;
    padding: 1.5rem 0 0;
}

.timeline-section-header {
    margin-bottom: 2.5rem;
}

.timeline-page-content .timeline-page-intro {
    margin-bottom: 2.5rem;
}

.timeline::before {
    content: '';
    position: absolute;
    top: 0;
    bottom: 0;
    left: 20px;
    width: 1px;
    background: linear-gradient(to bottom, rgba(0, 102, 255, 0.15), rgba(0, 102, 255, 0.5), rgba(0, 102, 255, 0.15));
}

.timeline-item {
    position: relative;
    display: grid;
    grid-template-columns: 40px 1fr;
    gap: 1.5rem;
    padding: 0 0 2.5rem;
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.timeline-dot {
    position: relative;
    z-index: 1;
    width: 40px;
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding-top: 0.45rem;
}

.timeline-dot-inner {
    display: block;
    width: 14px;
    height: 14px;
    background: #fff;
    border: 3px solid var(--color-primary, #0066ff);
    border-radius: 50%;
    box-shadow: 0 0 0 6px rgba(0, 102, 255, 0.08);
}

.timeline-content {
    min-width: 0;
    padding-bottom: 0.25rem;
}

.timeline-date {
    display: inline-block;
    margin-bottom: 0.8rem;
    font-size: 0.82rem;
    font-weight: 700;
    letter-spacing: 0.04em;
    color: var(--color-primary, #0066ff);
}

.timeline-title {
    margin: 0 0 0.6rem;
    font-size: 1.5rem;
    line-height: 1.35;
    font-weight: 700;
    color: var(--color-text, #1f2937);
}

.timeline-desc {
    margin: 0;
    max-width: 720px;
    font-size: 1rem;
    line-height: 1.8;
    color: var(--color-text-light, #6b7280);
}

.timeline-media {
    margin-top: 1.25rem;
    max-width: 720px;
}

.timeline-media img {
    display: block;
    width: 100%;
    height: auto;
    border-radius: 6px;
    object-fit: cover;
}

.timeline-layout-alternate::before {
    left: 50%;
    transform: translateX(-50%);
}

.timeline-layout-alternate .timeline-item {
    grid-template-columns: 1fr 40px 1fr;
    gap: 0;
}

.timeline-layout-alternate .timeline-dot {
    grid-column: 2;
}

.timeline-layout-alternate .timeline-content {
    max-width: 100%;
}

.timeline-layout-alternate .timeline-item-left .timeline-content {
    grid-column: 1;
    text-align: right;
    padding-right: 2.5rem;
}

.timeline-layout-alternate .timeline-item-right .timeline-content {
    grid-column: 3;
    padding-left: 2.5rem;
}

.timeline-layout-alternate .timeline-item-left .timeline-media {
    margin-left: auto;
}

@media (max-width: 768px) {
    .section-timeline {
        padding: 3rem 0;
    }

    .timeline {
        padding-top: 1rem;
    }

    .timeline::before {
        left: 14px;
    }

    .timeline-item {
        grid-template-columns: 28px 1fr;
        gap: 1rem;
        padding-bottom: 2rem;
    }

    .timeline-dot {
        width: 28px;
        padding-top: 0.35rem;
    }

    .timeline-dot-inner {
        width: 12px;
        height: 12px;
        border-width: 2px;
        box-shadow: 0 0 0 4px rgba(0, 102, 255, 0.08);
    }

    .timeline-date {
        margin-bottom: 0.6rem;
        font-size: 0.75rem;
    }

    .timeline-title {
        font-size: 1.1rem;
        margin-bottom: 0.45rem;
    }

    .timeline-desc {
        font-size: 0.92rem;
        line-height: 1.7;
    }

    .timeline-media {
        margin-top: 1rem;
    }

    .timeline-layout-alternate::before {
        left: 14px;
        transform: none;
    }

    .timeline-layout-alternate .timeline-item {
        grid-template-columns: 28px 1fr;
        gap: 1rem;
    }

    .timeline-layout-alternate .timeline-dot {
        grid-column: 1;
    }

    .timeline-layout-alternate .timeline-item-left .timeline-content,
    .timeline-layout-alternate .timeline-item-right .timeline-content {
        grid-column: 2;
        text-align: left;
        padding-left: 0;
        padding-right: 0;
    }
}