/* 基本样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* 头部样式 */
header {
    background-color: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: #3498db;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 1.5rem;
    position: relative;
}

nav ul li a {
    text-decoration: none;
    color: #555;
    font-weight: 500;
    transition: color 0.3s;
}

nav ul li a:hover,
nav ul li a.active {
    color: #3498db;
}

/* 下拉菜单 */
.dropdown-menu {
    position: absolute;
    top: 100%;
    right: 0;
    background-color: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    border-radius: 4px;
    width: 150px;
    display: none;
    z-index: 10;
}

#user-menu:hover .dropdown-menu {
    display: block;
}

.dropdown-menu a {
    display: block;
    padding: 10px 15px;
    border-bottom: 1px solid #eee;
}

.dropdown-menu a:last-child {
    border-bottom: none;
}

/* 主内容区域 */
main {
    padding: 2rem 0;
    min-height: calc(100vh - 150px);
}

.posts-container {
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    padding: 2rem;
}

.posts-container h2 {
    margin-bottom: 1.5rem;
    color: #2c3e50;
    border-bottom: 2px solid #eee;
    padding-bottom: 0.5rem;
}

.posts-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.post-card {
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
}

.post-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.post-image {
    height: 180px;
    overflow: hidden;
}

.post-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s;
}

.post-card:hover .post-image img {
    transform: scale(1.05);
}

.post-content {
    padding: 1.5rem;
}

.post-title {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

.post-meta {
    font-size: 0.85rem;
    color: #7f8c8d;
    margin-bottom: 0.75rem;
}

.post-excerpt {
    color: #555;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.read-more {
    display: inline-block;
    color: #3498db;
    font-weight: 500;
    text-decoration: none;
}

.read-more:hover {
    text-decoration: underline;
}

/* 表单样式 */
.form-container {
    max-width: 500px;
    margin: 0 auto;
    background-color: #fff;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #2c3e50;
}

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-control:focus {
    border-color: #3498db;
    outline: none;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: #3498db;
    color: #fff;
    border: none;
    border-radius: 4px;
    font-size: 1rem;
    cursor: pointer;
    transition: background-color 0.3s;
}

.btn:hover {
    background-color: #2980b9;
}

.btn-secondary {
    background-color: #95a5a6;
}

.btn-secondary:hover {
    background-color: #7f8c8d;
}

/* 文章详情页 */
.post-detail {
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    padding: 2rem;
}

.post-header {
    margin-bottom: 2rem;
}

.post-header h1 {
    font-size: 2.5rem;
    color: #2c3e50;
    margin-bottom: 0.5rem;
}

.post-header .post-meta {
    font-size: 0.9rem;
    color: #7f8c8d;
}

.post-body {
    line-height: 1.8;
    color: #333;
    margin-bottom: 2rem;
}

.post-body p {
    margin-bottom: 1.5rem;
}

.post-body img {
    max-width: 100%;
    border-radius: 4px;
    margin: 1.5rem 0;
}

/* 评论区 */
.comments-section {
    margin-top: 3rem;
    border-top: 1px solid #eee;
    padding-top: 2rem;
}

.comments-section h3 {
    margin-bottom: 1.5rem;
    color: #2c3e50;
}

.comment {
    background-color: #f9f9f9;
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.comment-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.75rem;
}

.comment-author {
    font-weight: 500;
    color: #2c3e50;
}

.comment-date {
    font-size: 0.85rem;
    color: #7f8c8d;
}

.comment-body {
    color: #555;
}

.comment-form {
    margin-top: 2rem;
}

.comment-form textarea {
    height: 120px;
    resize: vertical;
}

/* 页脚样式 */
footer {
    background-color: #2c3e50;
    color: #ecf0f1;
    padding: 2rem 0;
    text-align: center;
}

/* 工具类 */
.hidden {
    display: none !important;
}

.loading {
    text-align: center;
    padding: 2rem;
    color: #7f8c8d;
}

.alert {
    padding: 1rem;
    border-radius: 4px;
    margin-bottom: 1.5rem;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-danger {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header .container {
        flex-direction: column;
    }
    
    nav ul {
        margin-top: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    nav ul li {
        margin: 0.5rem;
    }
    
    .posts-list {
        grid-template-columns: 1fr;
    }
    
    .post-header h1 {
        font-size: 2rem;
    }
}