/* ========================================
   发展历程 - History Timeline Section
   简洁大气设计
   ======================================== */

.history-section {
    padding: 100px 0 120px;
    background: #0a0a0f;
    position: relative;
}

.history-section .container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
}

/* 标题区域 */
.history-section .section-header {
    text-align: center;
    margin-bottom: 80px;
}

.history-section .section-header .tit {
    color: #ffffff;
    margin-bottom: 20px;
    font-weight: 600;
    letter-spacing: 0.02em;
}

.history-section .section-header .p {
    color: rgba(255, 255, 255, 0.5);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.8;
}

/* ========================================
   时间线主体
   ======================================== */
.history-timeline {
    position: relative;
    max-width: 1200px;
    margin: 0 auto;
}

/* 中央时间线 */
.history-timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 1px;
    height: 100%;
    background: rgba(255, 255, 255, 0.15);
}

/* ========================================
   时间线项目
   ======================================== */
.history-item {
    position: relative;
    display: flex;
    margin-bottom: 0;
    padding: 40px 0;
}

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

/* 奇数项 - 左侧 */
.history-item:nth-child(odd) {
    padding-right: calc(50% + 80px);
    padding-left: 0;
    justify-content: flex-end;
}

/* 偶数项 - 右侧 */
.history-item:nth-child(even) {
    padding-left: calc(50% + 80px);
    padding-right: 0;
    justify-content: flex-start;
}

/* 时间线节点 */
.history-item::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 50px;
    transform: translateX(-50%);
    width: 11px;
    height: 11px;
    background: #ffffff;
    border-radius: 50%;
    z-index: 2;
}

/* 连接线 */
.history-item::after {
    content: '';
    position: absolute;
    top: 55px;
    width: 60px;
    height: 1px;
    background: rgba(255, 255, 255, 0.15);
}

.history-item:nth-child(odd)::after {
    right: calc(50% + 5px);
}

.history-item:nth-child(even)::after {
    left: calc(50% + 5px);
}

/* ========================================
   卡片样式
   ======================================== */
.history-card {
    max-width: 480px;
    width: 100%;
}

/* 年份 */
.history-year {
    color: #ffffff;
    font-size: 48px;
    font-weight: 300;
    letter-spacing: 0.05em;
    margin-bottom: 20px;
    line-height: 1;
}

.history-year span {
    display: block;
}

/* 内容区域 */
.history-content {
    color: rgba(255, 255, 255, 0.6);
    line-height: 1.9;
    font-size: 15px;
}

.history-content p {
    margin: 0;
}

/* 内容中的高亮 */
.history-content strong,
.history-content b {
    color: #ffffff;
    font-weight: 500;
}

/* ========================================
   平板适配 (768px - 1024px)
   ======================================== */
@media (max-width: 1024px) {
    .history-section {
        padding: 80px 0 100px;
    }

    .history-section .container {
        padding: 0 30px;
    }

    .history-section .section-header {
        margin-bottom: 60px;
    }

    .history-item:nth-child(odd) {
        padding-right: calc(50% + 50px);
    }

    .history-item:nth-child(even) {
        padding-left: calc(50% + 50px);
    }

    .history-item::after {
        width: 35px;
    }

    .history-card {
        max-width: 380px;
    }

    .history-year {
        font-size: 40px;
        margin-bottom: 16px;
    }

    .history-content {
        font-size: 14px;
    }
}

/* ========================================
   移动端适配 (< 768px)
   单列布局
   ======================================== */
@media (max-width: 768px) {
    .history-section {
        padding: 60px 0 80px;
    }

    .history-section .container {
        padding: 0 24px;
    }

    .history-section .section-header {
        margin-bottom: 50px;
    }

    .history-section .section-header .tit {
        font-size: 32px !important;
    }

    .history-section .section-header .p {
        font-size: 15px !important;
    }

    /* 时间线移到左侧 */
    .history-timeline::before {
        left: 0;
        transform: none;
    }

    /* 所有项目左对齐 */
    .history-item {
        padding: 30px 0 30px 40px !important;
        justify-content: flex-start !important;
    }

    .history-item::before {
        left: 0;
        top: 38px;
        transform: translateX(-50%);
        width: 9px;
        height: 9px;
    }

    .history-item::after {
        left: 5px !important;
        right: auto !important;
        top: 42px;
        width: 25px;
    }

    .history-card {
        max-width: 100%;
    }

    .history-year {
        font-size: 36px;
        margin-bottom: 14px;
    }

    .history-content {
        font-size: 14px;
        line-height: 1.8;
    }
}

/* ========================================
   小屏手机适配 (< 480px)
   ======================================== */
@media (max-width: 480px) {
    .history-section {
        padding: 50px 0 60px;
    }

    .history-section .container {
        padding: 0 20px;
    }

    .history-section .section-header {
        margin-bottom: 40px;
    }

    .history-section .section-header .tit {
        font-size: 26px !important;
    }

    .history-section .section-header .p {
        font-size: 14px !important;
    }

    .history-item {
        padding: 24px 0 24px 32px !important;
    }

    .history-item::before {
        width: 7px;
        height: 7px;
        top: 32px;
    }

    .history-item::after {
        top: 35px;
        width: 20px;
    }

    .history-year {
        font-size: 30px;
        margin-bottom: 12px;
    }

    .history-content {
        font-size: 13px;
        line-height: 1.75;
    }
}

/* ========================================
   动画效果
   ======================================== */
.history-item {
    opacity: 0;
    transform: translateY(20px);
}

.history-item.wow {
    opacity: 1;
    transform: translateY(0);
    transition: opacity 0.6s ease, transform 0.6s ease;
}