/* ========================================
   时间轴里程碑样式
   ======================================== */

/* 时间轴区块 */
.timeline-section {
    padding: 100px 0;
    background: #f8fafc;
}

/* 时间轴容器 */
.timeline-wrapper {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
    padding: 40px 0;
}

/* 中间的时间轴线 */
.timeline-line {
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(to bottom, #dc2626, #f97316);
    transform: translateX(-50%);
}

/* 里程碑列表 */
.timeline-milestones {
    position: relative;
    display: flex;
    flex-direction: column;
    gap: 25px;
}

/* 单个里程碑项 */
.milestone-item {
    position: relative;
    display: flex;
    align-items: center;
    width: 100%;
}

/* 奇数项 - 左侧显示 */
.milestone-item:nth-child(odd) {
    flex-direction: row;
    text-align: right;
}

.milestone-item:nth-child(odd) .milestone-content {
    margin-right: 60px;
    margin-left: 0;
}

/* 左侧卡片的header - 年份在右，标题在左 */
.milestone-item:nth-child(odd) .milestone-header {
    flex-direction: row-reverse;
    justify-content: flex-start;
}

/* 偶数项 - 右侧显示 */
.milestone-item:nth-child(even) {
    flex-direction: row-reverse;
    text-align: left;
}

.milestone-item:nth-child(even) .milestone-content {
    margin-left: 60px;
    margin-right: 0;
}

/* 圆点标记 */
.milestone-dot {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 20px;
    height: 20px;
    background: #dc2626;
    border-radius: 50%;
    border: 4px solid white;
    box-shadow: 0 0 0 4px rgba(220, 38, 38, 0.2);
    z-index: 10;
    transition: all 0.3s ease;
}

/* 悬停时圆点放大 */
.milestone-item:hover .milestone-dot {
    transform: translateX(-50%) scale(1.3);
    box-shadow: 0 0 0 8px rgba(220, 38, 38, 0.15);
}

/* 高亮项样式 */
.milestone-item.highlight .milestone-dot {
    background: #f97316;
    box-shadow: 0 0 0 4px rgba(249, 115, 22, 0.2);
}

/* 未来项样式 - 带脉冲动画 */
.milestone-item.future .milestone-dot {
    background: linear-gradient(135deg, #dc2626, #f97316);
    animation: pulse-dot 2s ease-in-out infinite;
}

/* 圆点脉冲动画 */
@keyframes pulse-dot {
    0%, 100% {
        box-shadow: 0 0 0 4px rgba(220, 38, 38, 0.2);
    }
    50% {
        box-shadow: 0 0 0 8px rgba(220, 38, 38, 0.1);
    }
}

/* 里程碑内容卡片 */
.milestone-content {
    width: calc(50% - 60px);
    padding: 24px 32px;
    background: white;
    border-radius: 16px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    transition: all 0.3s ease;
}

/* 悬停时卡片上浮 */
.milestone-item:hover .milestone-content {
    transform: translateY(-5px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

/* 年份和标题容器 */
.milestone-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 8px;
}

/* 年份标签 */
.milestone-year {
    display: inline-block;
    padding: 4px 12px;
    background: linear-gradient(135deg, #dc2626 0%, #b91c1c 100%);
    color: white;
    font-size: 0.875rem;
    font-weight: 700;
    border-radius: 9999px;
}

/* 高亮项年份标签 */
.milestone-item.highlight .milestone-year {
    background: linear-gradient(135deg, #f97316, #ea580c);
}

/* 未来项年份标签 */
.milestone-item.future .milestone-year {
    background: linear-gradient(135deg, #dc2626, #f97316);
}

/* 里程碑标题 */
.milestone-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 8px;
}

/* 里程碑描述 */
.milestone-desc {
    font-size: 0.95rem;
    color: #64748b;
    line-height: 1.6;
}

/* ========================================
   原来的卡片式布局样式（保留）
   ======================================== */

/* 发展历程卡片区块 */
.about-timeline {
    padding: 100px 0;
    background: #ffffff;
}

/* 卡片网格布局 */
.timeline-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

/* 时间轴卡片 */
.timeline-card {
    position: relative;
    background: white;
    padding: 2rem;
    border-radius: 16px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    transition: all 0.3s ease;
    overflow: hidden;
}

.timeline-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(135deg, #dc2626 0%, #b91c1c 100%);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.timeline-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

.timeline-card:hover::before {
    transform: scaleX(1);
}

/* 卡片年份 */
.timeline-card-year {
    position: absolute;
    top: 1.5rem;
    right: 1.5rem;
    font-size: 2.5rem;
    font-weight: 800;
    color: rgba(220, 38, 38, 0.1);
    line-height: 1;
}

/* 卡片标题 */
.timeline-card-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 0.75rem;
    padding-right: 80px;
}

/* 卡片描述 */
.timeline-card-desc {
    font-size: 0.95rem;
    color: #64748b;
    line-height: 1.6;
}

/* ========================================
   响应式设计 - 移动端
   ======================================== */
@media (max-width: 768px) {
    .timeline-line {
        left: 20px;
    }
    
    .milestone-item,
    .milestone-item:nth-child(odd),
    .milestone-item:nth-child(even) {
        flex-direction: row;
        text-align: left;
    }
    
    .milestone-item .milestone-content,
    .milestone-item:nth-child(odd) .milestone-content,
    .milestone-item:nth-child(even) .milestone-content {
        width: calc(100% - 60px);
        margin-left: 60px;
        margin-right: 0;
    }
    
    .milestone-dot {
        left: 20px;
    }
    
    /* 卡片布局移动端 */
    .timeline-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 1024px) {
    .timeline-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}