/* 1. 整体背景改为极浅的灰色，凸显白色卡片 */
body {
    background-color: #f8f9fa;
}

/* 2. 头部资料区 */
.profile-hero {
    background-color: #ffffff;
    padding: 3rem 0 2rem 0;
    border-bottom: 1px solid #ebeef5;
}
.profile-avatar {
    width: 90px;
    height: 90px;
    object-fit: cover;
    border-radius: 50%;
    border: 4px solid #fff;
    box-shadow: 0 4px 14px rgba(0,0,0,0.08);
}

/* 3. 现代化的下划线导航 */
.nav-underline {
    border-bottom: 1px solid #ebeef5; /* 增加一条底线轨道 */
}
.nav-underline .nav-link {
    color: #606266;
    padding: 0.8rem 1rem;
    font-weight: 500;
    border-bottom: 2px solid transparent;
    margin-bottom: -1px; /* 覆盖底线 */
    transition: all 0.2s;
}
.nav-underline .nav-link:hover { color: #303133; }
.nav-underline .nav-link.active {
    color: #0d6efd;
    border-bottom-color: #0d6efd;
    font-weight: 600;
}

/* 4. ★ 核心优化：独立悬浮的卡片设计 ★ */
.post-card {
    background-color: #ffffff;
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 16px; /* 卡片之间的间距 */
    border: 1px solid rgba(0,0,0,0.04);
    box-shadow: 0 2px 8px rgba(0,0,0,0.02); /* 极其轻微的阴影 */
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.post-card:hover {
    transform: translateY(-2px); /* 鼠标悬浮时微微上浮 */
    box-shadow: 0 8px 16px rgba(0,0,0,0.06);
}

/* 5. 略缩图优化 */
.post-thumbnail {
    width: 130px;
    height: 86px;
    object-fit: cover;
    border-radius: 8px;
    border: 1px solid #f0f0f0;
}
@media (max-width: 576px) {
    .post-thumbnail { width: 100px; height: 68px; }
    .post-card { padding: 15px; } /* 移动端减小内边距 */
}

/* 6. 搜索框优化 */
.search-pill {
    background-color: #f1f3f5;
    border-radius: 20px;
    overflow: hidden;
    padding: 2px 10px;
}
.search-pill input {
    background: transparent;
    border: none;
    box-shadow: none !important;
}

/* 给水印加个极其轻微的互动效果 */
.d-inline-flex:hover {
    transform: translateY(-2px);
    background-color: #ffffff !important;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}