/* 基础平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 自定义字体栈，确保本地化和系统兼容 */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
}

/* Logo 艺术字特效增强 */
.logo-art {
    font-family: "STKaiti", "KaiTi", "楷体", serif;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.05);
}

/* 动画延迟类 */
.animation-delay-200 {
    animation-delay: 0.2s;
}
.animation-delay-400 {
    animation-delay: 0.4s;
}
.animation-delay-600 {
    animation-delay: 0.6s;
}

/* Hero 区域文字入场动画 */
.animate-fade-in-up {
    animation: fadeInUp 0.8s ease-out forwards;
    opacity: 0;
    transform: translateY(30px);
}

@keyframes fadeInUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 滚动渐入动画 */
.fade-in-section {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in-section.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* 导航栏阴影过渡 */
.nav-scrolled {
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

/* 背景网格纹理（用于深色区块） */
.bg-pattern-grid {
    background-image: linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
                      linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
    background-size: 40px 40px;
}

/* 选中高亮颜色定制 */
::selection {
    background-color: #1e3a8a; /* blue-900 */
    color: #ffffff;
}

::-moz-selection {
    background-color: #1e3a8a;
    color: #ffffff;
}

/* 移动端菜单展开时的最大高度控制 */
#mobile-menu.open {
    max-height: 500px;
}

/* 确保图片在加载时不会引起布局偏移 */
img {
    max-width: 100%;
    height: auto;
}