/* ========== 二级菜单：移动端 dropdown，PC 保持横排 tab ========== */
.subnav-mobile {
    display: none;
}

.subnav-desktop {
    display: flex;
}

@media (max-width: 1023px) {
    .subnav-mobile {
        display: block;
    }

    .subnav-desktop {
        display: none;
    }
}

.subnav-dropdown {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.35s ease, opacity 0.25s ease, padding 0.25s ease;
}

.subnav-dropdown.is-open {
    max-height: 400px;
    opacity: 1;
}

.subnav-trigger .arrow {
    transition: transform 0.3s ease;
    transform: translateY(-50%);
    top: 50%;
}

.subnav-trigger[aria-expanded="true"] .arrow {
    transform: translateY(-50%) rotate(180deg);
}

/* 时间线 */
.timeline-wrap {
    --axis-line-x: 24px;
    --axis-dot-x: 0;
    --dot-y: 100px;
}

@media (min-width: 768px) {
    .timeline-wrap {
        --axis-line-x: 50%;
        --axis-dot-x: 50%;
        --dot-y: 50%;
    }
}

.timeline-wrap .axis-line {
    position: absolute;
    left: var(--axis-line-x);
    top: 0;
    bottom: 0;
    width: 2px;
    transform: translateX(-50%);
    background: linear-gradient(to bottom, rgba(198, 165, 36, 0), rgba(198, 165, 36, 0.3), rgba(198, 165, 36, 0));
    z-index: 0;
}

.history-row .axis-dot {
    position: absolute;
    left: var(--axis-dot-x);
    top: var(--dot-y);
    transform: translate(-50%, -50%);
    width: 16px;
    height: 16px;
    background: #00301c;
    border: 2px solid #c6a524;
    border-radius: 50%;
    box-shadow: 0 0 15px rgba(198, 165, 36, 0.8);
    z-index: 1;
    transition: all 0.3s ease;
}

.history-row:hover .axis-dot {
    background: #c6a524;
    transform: translate(-50%, -50%) scale(1.5);
}