/* 重置样式确保全屏 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: #3f3f3f;
    position: relative;
    min-height: 100vh;
}

/* 3D背景容器 - 固定在全屏最底层 */
.title-banner {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    margin: 0;
    overflow: hidden;
    background: #000;
    z-index: -1;
}

.banner-iframe {
    width: 100%;
    height: 100%;
    border: none;
    display: block;
}

/* 遮罩层 */
.title-banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        135deg,
        rgba(0, 0, 0, 0.4) 0%,
        rgba(0, 180, 219, 0.2) 50%,
        rgba(0, 0, 0, 0.4) 100%
    );
    z-index: 5;
    pointer-events: none;
}

/* 主内容区域 */
main {
    position: relative;
    z-index: 1;
    max-width: 1200px;
    min-height: 100vh;
    margin: 0 auto;
    padding: 120px 20px 60px;
    box-sizing: border-box;
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* 内容区域 */

/* 页面大标题 - 在内容区域上方 */
.page-title {
    text-align: center;
    font-size: 3.5em;
    font-weight: bold;
    color: #ffffff;
}

/* 分类导航 */
.category-nav {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin: 30px 0;
    flex-wrap: wrap;
}

.category-btn {
    background: #f8f9fa;
    border: 2px solid #d7d7d7;
    color: #000000;
    padding: 12px 24px;
    border-radius: 25px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
}

.category-btn:hover {
    background: #c2c2c2;
    color: white;
    transform: translateY(-2px);
}

.category-btn.active {
    background: #000000;
    color: white;
}

/* 文章网格布局 */
#article-list {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    width: 100%;
}

/* 文章条目 */
.article-entry {
    background-color: #ffffff;
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    height: 100%;
    box-sizing: border-box;
    border: 1px solid rgba(0, 0, 0, 0.1);
}

.article-entry:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.article-entry h2 {
    margin-top: 0;
    font-size: 1.5em;
    line-height: 1.3;
    margin-bottom: 15px;
}

.article-entry h2 a {
    text-decoration: none;
    color: #2c3e50;
}

.article-meta {
    font-size: 0.9em;
    color: #7f8c8d;
    margin-bottom: 15px;
}

.article-summary {
    line-height: 1.6;
    flex-grow: 1;
    margin-bottom: 20px;
    color: #555;
}

.read-more {
    display: inline-block;
    margin-top: auto;
    text-decoration: none;
    color: #fff;
    background-color: #000000;
    padding: 12px 24px;
    border-radius: 6px;
    font-weight: bold;
    text-align: center;
    transition: background-color 0.3s ease;
}

.read-more:hover {
    background-color: #767676;
}

/* 其他样式 */
.filter-info {
    display: none !important;
}

.no-articles {
    text-align: center;
    padding: 40px;
    color: #666;
    font-style: italic;
}

.article-tags {
    margin: 8px 0;
}

.article-tag {
    display: inline-block;
    background: #e1ecf4;
    color: #ffffff;
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 12px;
    margin-right: 5px;
    margin-bottom: 5px;
}

.data-insight-tag {
    background: #000000;
    color: white;
}

.brand-strategy-tag {
    background: #27ae60;
    color: white;
}

.brand-activity-tag {
    background: #e74c3c;
    color: white;
}

/* ===== 文章页面特殊样式 ===== */
/* 当页面是文章页面时，隐藏3D背景，显示白色背景 */
body.article-page .title-banner {
    display: none !important; /* 完全隐藏3D背景 */
}

body.article-page {
    background-color: #ffffff !important; /* 整个页面白色背景 */
}

body.article-page main {
    background-color: #ffffff !important; /* 主内容区域白色背景 */
    z-index: 1; /* 确保在顶层 */
}
body.article-page #header-placeholder,
body.article-page #footer-placeholder {
    background-color: #ffffff !important;
    position: relative;
    z-index: 2;
}

/* 文章内容区域样式 */
#article-content {
    background-color: #ffffff;
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    padding: 40px;
    line-height: 1.7;
    box-sizing: border-box;
}

/* 文章页面返回链接样式 */
body.article-page .back-link {
    display: inline-flex !important;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background: transparent;
    border: none;
    border-radius: 50%;
    color: #878787;
    text-decoration: none;
    transition: all 0.3s ease;
    position: fixed;
    top: 120px;
    left: 20px;
    z-index: 1000;
}



body.article-page .back-link span {
    font-size: 32px;
    font-weight: bold;
    line-height: 1;
}


/* 错误消息样式 */
.error-message {
    color: #dc3545;
    padding: 20px;
    background: #f8d7da;
    border-radius: 8px;
    border: 1px solid #f5c6cb;
}

/* 响应式设计 */
@media (max-width: 1024px) {
    #article-list {
        grid-template-columns: repeat(2, 1fr);
        gap: 25px;
    }
    
    .page-title {
        font-size: 3em;
    }
}

@media (max-width: 768px) {
    #article-list {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    main {
        padding: 100px 15px 40px;
    }
    
    .content-container {
        padding: 25px;
    }
    
    .page-title {
        font-size: 2.5em;
        margin-bottom: 30px;
    }
    
    .category-nav {
        gap: 0.5rem;
    }
    
    .category-btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
    
    .article-entry {
        padding: 25px;
    }
    
    /* 文章页面响应式 */
    body.article-page main {
        padding: 80px 15px 40px;
    }
    
    #article-content {
        padding: 25px;
    }
}

@media (max-width: 480px) {
    main {
        padding: 80px 10px 30px;
    }
    
    .page-title {
        font-size: 2em;
        margin-bottom: 25px;
    }
    
    .category-btn {
        padding: 8px 16px;
        font-size: 0.8rem;
    }
    
    .article-entry {
        padding: 20px;
    }
    
    .content-container {
        padding: 20px;
    }
    
    /* 文章页面响应式 */
    body.article-page main {
        padding: 60px 10px 30px;
    }
    
    #article-content {
        padding: 20px;
    }
}