/* 引入现代无衬线字体：思源黑体风格，极简优雅 */
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@100;300;400;500&display=swap');

/* 全局基础设置：重置与字体定义 */
:root {
    --primary-text: #1a1a1a;
    --secondary-text: #666666;
    --bg-color: #ffffff;
    --nav-bg: rgba(255, 255, 255, 0.9);
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    -webkit-font-smoothing: antialiased; /* 让字体在Mac上更清晰 */
    -moz-osx-font-smoothing: grayscale;
    background-color: var(--bg-color);
    color: var(--primary-text);
    overflow-x: hidden; /* 防止意外横向滚动 */
    line-height: 1.6;
}

/* 平滑滚动体验 */
html {
    scroll-behavior: smooth;
}

/* 导航栏：毛玻璃效果，保持顶部固定时的通透感 */
.nav-blur {
    background-color: var(--nav-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transition: all 0.3s ease;
    border-bottom: 1px solid rgba(0,0,0,0.03);
}

/* 极简链接样式：去除默认下划线，自定义细微交互 */
a {
    text-decoration: none;
    color: inherit;
    transition: color 0.3s ease;
}

/* 图片容器：用于包裹图片实现悬停放大效果 */
.img-container {
    overflow: hidden;
    position: relative;
    display: block;
    width: 100%;
    background-color: #f5f5f5; /* 图片加载前的占位色 */
}

/* 图片本身：设置慢速优雅的缓动曲线 */
.img-hover-scale {
    transition: transform 1.2s cubic-bezier(0.19, 1, 0.22, 1), opacity 0.5s ease;
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    will-change: transform;
}

/* 悬停状态：轻微放大1.03-1.05倍，保持克制 */
.img-container:hover .img-hover-scale {
    transform: scale(1.05);
}

/* 遮罩层：用于显示文字或变亮效果 */
.hover-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.15); /* 轻微暗化，突出白色文字 */
    opacity: 0;
    transition: opacity 0.6s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none; /* 让鼠标事件穿透到图片 */
    z-index: 10;
}

.img-container:hover .hover-overlay {
    opacity: 1;
}

/* 页面入场淡入动画 */
@keyframes fadeInUp {
    from { 
        opacity: 0; 
        transform: translateY(20px); 
    }
    to { 
        opacity: 1; 
        transform: translateY(0); 
    }
}

.fade-in {
    opacity: 0; /* 初始隐藏 */
    animation: fadeInUp 1.2s cubic-bezier(0.22, 1, 0.36, 1) forwards;
}

.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }
.delay-500 { animation-delay: 0.5s; }

/* 轮播图特定样式 */
.carousel-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1.8s ease-in-out; /* 极慢的淡入淡出，营造电影感 */
    z-index: 1;
}

.carousel-slide.active {
    opacity: 1;
    z-index: 2;
}

/* 轮播图文字层 */
.carousel-caption {
    z-index: 3;
    pointer-events: none; /* 文字不阻挡点击 */
}

/* 极简页脚规范 */
.minimal-footer {
    border-top: 1px solid rgba(0, 0, 0, 0.05);
    padding: 3rem 0;
    margin-top: auto;
    width: 100%;
    text-align: center;
}

/* 文本排版优化 */
.tracking-wide-custom {
    letter-spacing: 0.2em; /* 标题增加字间距 */
}

.text-justify-custom {
    text-align: justify;
    text-justify: inter-ideograph;
}

/* 选中态颜色，保持黑白灰调性 */
::selection {
    background: #e0e0e0;
    color: #000;
}

/* 针对移动端的微调 */
@media (max-width: 768px) {
    .img-hover-scale {
        transition: transform 0.5s ease;
    }
    .carousel-slide {
        background-position: center;
    }
}