/* 淡入效果 */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.fade-in {
    animation: fadeIn 1s ease-in-out;
}

/* 悬停效果 */
a:hover, img:hover {
    transform: scale(1.05);
    transition: transform 0.3s ease;
}

/* 滚动动画 */
.scroll-animation {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.scroll-animation.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 导航栏动态下划线 */
h2 a {
    position: relative;
    padding-bottom: 3px;
}
h2 a:hover {text-decoration : none; }
h2 a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--link-color);
    transition: width 0.3s ease;
}
h2 a:hover::after {
    width: 100%;
}