body {
    font-family: system-ui;
    margin: 0;
    padding-top: 75px;
    min-height: 100vh;        /* 保证背景填满视口 */
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
}

    @keyframes colorBreath {
        0% { background: #667eea; }   /* 蓝紫 */
        33% { background: #764ba2; }   /* 深紫 */
        66% { background: #e74c3c; }   /* 红色 */
        100% { background: #667eea; }  /* 回到起点 */
}
.hero-image {
    position: relative;
    height: 50vh;
    overflow: hidden;   /* 防止图片溢出 */
}
.hero-img {
    width: 100%;
    height: 100%;
    object-fit: cover;  /* 类似 background-size: cover */
    display: block;
    animation: fadeIn 1s ease forwards;
}
@keyframes fadeIn { /*照片淡入*/
    from {
        opacity: 0;   
    }
    to {
        opacity: 1;   
    }
}
.hero-image::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 50vh;
    background: rgba(0, 0, 0, 0.2); 
    pointer-events: none;  
}
.container {
    width: 90%;
    max-width: 800px;
    margin: 0 auto;
    padding: 40px 20px;
    box-sizing: border-box;
}
.tagline {
    font-size: 1.5rem;
    opacity: 0.8;
    text-align: center; 
}
/* 固定顶栏 */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(10px);
    z-index: 100;
    box-sizing: border-box;
}

/* 站点名称 */
.site-title {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: 1px;
}

/* 导航链接 */
.site-nav a {
    color: white;
    text-decoration: none;
    margin-left: 2rem;
    font-size: 1rem;
    opacity: 0.8;
    transition: opacity 0.2s;
}

.site-nav a:hover {
    opacity: 1;
    text-decoration: underline;
}
.language-switcher {
    position: relative;  /* 让下拉菜单相对于此定位 */
    top: auto;
    right: auto;
}

.language-switcher a {
    color: white;
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.2s;
}

.language-switcher a:hover {
    opacity: 1;
    text-decoration: underline;
}

.language-switcher a.active {
    font-weight: bold;
    opacity: 1;
    text-decoration: underline;
    color: #ffd700;
}

/* 地球图标和箭头区域 */
.language-toggle {
    display: flex;
    align-items: center;
    gap: 4px;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(8px);
    padding: 8px 12px;
    border-radius: 30px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    transition: background 0.3s;
}

.language-toggle:hover {
    background: rgba(255, 255, 255, 0.3);
}

.earth-icon {
    display: inline-flex;   /* 让图标与父级 flex 对齐 */
    align-items: center;
    justify-content: center;
    line-height: 1;
    width: 1.4rem;          /* 可选，确保容器大小一致 */
    height: 1.4rem;
}

/* 下拉菜单 */
.language-dropdown {
    display: none;           /* 添加这一行 */
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    left: auto;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(8px);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.2);
    min-width: 120px;
    z-index: 101;
}

.language-dropdown.show {
    display: block;
}

.language-dropdown a {
    display: block;
    padding: 12px 16px;
    color: white;
    text-decoration: none;
    font-size: 1rem;
    transition: background 0.2s;
    text-align: left;
}

.language-dropdown a:hover {
    background: rgba(255, 255, 255, 0.2);
}

.language-dropdown a.active {
    color: #ffd700;
    font-weight: bold;
    background: rgba(255, 215, 0, 0.1);
}

/* 当箭头旋转（可选，表示菜单打开） */
.language-toggle.open .arrow {
    transform: rotate(180deg);
}
footer {
    position: fixed;   /* 声明在页面底部固定 */
    left: 0;
    bottom: 0;
    width: 100%;
    text-align: center;
    padding: 10px 0;
    opacity: 0.6;        /* 半透明，不那么抢眼 */
    color: white;
}
footer p {
    font-size: 0.8rem;       /* 字体小一点 */
}
@media (max-width: 600px) {
    .site-header {
        padding: 0.8rem 1rem;
    }
    .site-title {
        font-size: 1.2rem;
    }
    .site-nav a {
        margin-left: 1rem;
        font-size: 0.9rem;
    }
    .hero-image {
        height: 40vh;   /* 小屏稍微减小 */
    }
    .container {
        padding: 20px;
    }
    .tagline {
        font-size: 1rem;
    }
    body {
        padding-top: 70px;
    }
}