/* ============================================================
   页眉整体样式
   ============================================================ */
.site-header {
    background: #2c3e50;
    /* 背景色深蓝灰 */
    color: white;
    padding: 0rem 2.5rem;
    margin-bottom: 1rem;
    border-radius: 8px;
    box-sizing: border-box;
}

/* ============================================================
   导航栏容器 - 使用 Flexbox 横向布局
   ============================================================ */
.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
}

/* ============================================================
   左侧标题和头像
   ============================================================ */
.nav-left {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.nav-left .site-avatar {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid #ff6f61;
    /* 头像边框与 header 边框一致 */
}

/* 网站标题 */
.navbar h1 {
    margin: 0;
    font-size: 1.5rem;
}

.navbar h1 a {
    color: white;
    text-decoration: none;
    font-weight: 700;
}

.navbar h1 a:hover {
    opacity: 0.8;
}

/* 网站描述文字 */
.navbar p {
    opacity: 0.8;
    margin: 0.3rem 0 0 0;
    font-size: 0.9rem;
}

/* ============================================================
   主导航列表 - 横向排列
   ============================================================ */
.nav-links {
    list-style: none;
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin: 0;
    padding: 0;
}

.nav-links>li {
    position: relative;
}

/* 导航链接样式 */
.nav-links a {
    color: white;
    text-decoration: none;
    padding: 0.3rem 1rem;
    display: block;
    border-radius: 4px;
    transition: background-color 0.2s ease;
}

.nav-links a:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

/* 下拉菜单样式 */
.nav-links .dropdown {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background-color: #34495e;
    list-style: none;
    padding: 0.5rem 0;
    margin: 0;
    min-width: 150px;
    border-radius: 4px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    z-index: 1000;
}

.nav-links li:hover .dropdown {
    display: block;
}

.nav-links .dropdown li {
    margin: 0;
}

.nav-links .dropdown a {
    padding: 0.5rem 1rem;
    white-space: nowrap;
}

.nav-links .dropdown a:hover {
    background-color: rgba(255, 255, 255, 0.15);
}

/* ============================================================
   响应式设计 - 移动端适配
   ============================================================ */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        align-items: flex-start;
    }

    .nav-left {
        margin-bottom: 0.5rem;
    }

    .nav-links {
        flex-direction: column;
        align-items: flex-start;
        width: 100%;
        gap: 0.5rem;
    }

    .nav-links .dropdown {
        position: static;
        display: none;
        background-color: rgba(255, 255, 255, 0.1);
        margin-top: 0.5rem;
    }

    .nav-links li:hover .dropdown {
        display: block;
    }
}