/* ===== 动画特效 ===== */
/* 卡片加载动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.b2-child-uisdc .article-card {
    animation: fadeInUp 0.6s ease forwards;
    opacity: 0;
}

/* 延迟动画效果 */
.b2-child-uisdc .article-card:nth-child(1) { animation-delay: 0.1s; }
.b2-child-uisdc .article-card:nth-child(2) { animation-delay: 0.2s; }
.b2-child-uisdc .article-card:nth-child(3) { animation-delay: 0.3s; }
.b2-child-uisdc .article-card:nth-child(4) { animation-delay: 0.4s; }
.b2-child-uisdc .article-card:nth-child(5) { animation-delay: 0.5s; }
.b2-child-uisdc .article-card:nth-child(6) { animation-delay: 0.6s; }

/* 悬停放大效果 */
@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.03); }
    100% { transform: scale(1); }
}

.b2-child-uisdc .article-card:hover {
    animation: pulse 0.8s ease;
}

/* 导航下划线动画 */
@keyframes underlineGrow {
    from { transform: scaleX(0); }
    to { transform: scaleX(1); }
}

.b2-child-uisdc .main-nav > li > a:hover:after {
    animation: underlineGrow 0.3s ease-out;
}

/* 页面滚动进度条 */
.b2-child-uisdc .progress-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: transparent;
    z-index: 9999;
}

.b2-child-uisdc .progress-bar {
    height: 4px;
    background: linear-gradient(to right, var(--uisdc-primary), #ff9a3a);
    width: 0%;
    transition: width 0.2s ease;
}