/* ==========================================================
   论坛首页 (Forum Index - discuz.php) 专属样式
   包含：SEO横幅、版块分区头部、两列版块网格列表等
   ========================================================== */

.seo-hero { background: var(--bg-surface); padding: 32px; border-radius: var(--radius-md); box-shadow: var(--shadow-sm); margin-top: 24px; margin-bottom: 24px; text-align: center; border: 1px solid var(--border-color); background-image: linear-gradient(120deg, rgba(59,130,246,0.05) 0%, transparent 100%); }
.seo-hero h1 { font-size: 1.8rem; font-weight: 800; color: var(--text-main); margin-bottom: 8px; letter-spacing: 1px; }
.seo-hero p { color: var(--text-muted); font-size: 1.05rem; }

.forum-group-hd { padding: 16px 20px; border-bottom: 1px solid var(--border-color); display: flex; justify-content: space-between; align-items: center; background: rgba(0,0,0,0.01); }
[data-theme="dark"] .forum-group-hd { background: rgba(255,255,255,0.01); }
.forum-group-hd h2 { font-size: 1.15rem; font-weight: 700; margin: 0; }
.forum-group-hd h2 a { color: var(--text-main); }
.forum-group-hd h2 a:hover { color: var(--primary-color); }

.forum-list { display: grid; grid-template-columns: repeat(2, 1fr); width: 100%; }
.forum-item { display: flex; gap: 16px; padding: 20px; border-bottom: 1px solid var(--border-color); border-right: 1px solid var(--border-color); transition: var(--transition); position: relative; }
.forum-item:nth-child(even) { border-right: none; }
.forum-item:nth-last-child(-n+2) { border-bottom: none; }
.forum-item:hover { transform: translateY(-3px); box-shadow: var(--shadow-hover); border-radius: var(--radius-sm); background: var(--bg-surface); z-index: 2; border-color: transparent; }

.forum-icon { width: 50px; height: 50px; flex-shrink: 0; display: flex; align-items: center; justify-content: center; }
.forum-icon img { width: 100%; height: 100%; max-width: 50px; max-height: 50px; object-fit: contain; border-radius: var(--radius-sm); }
.forum-icon-default { width: 50px; height: 50px; border-radius: var(--radius-sm); background: var(--bg-body); display: flex; align-items: center; justify-content: center; border: 1px solid var(--border-color); }
.forum-icon-default svg { width: 28px; height: 28px; fill: var(--text-muted); }

.forum-info { flex: 1; min-width: 0; display: flex; flex-direction: column; justify-content: center; }
.forum-name { font-size: 1.1rem; font-weight: 700; margin-bottom: 4px; display: block; color: var(--text-main); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.forum-desc { font-size: 0.85rem; color: var(--text-muted); margin-bottom: 8px; line-height: 1.4; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.forum-stats { font-size: 0.8rem; color: var(--text-muted); display: flex; gap: 16px; margin-bottom: 6px; }
.forum-stats span i { margin-right: 4px; opacity: 0.7; }
.forum-lastpost { font-size: 0.8rem; border-top: 1px dashed var(--border-color); padding-top: 6px; color: var(--text-muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.forum-lastpost a { color: var(--text-muted); }
.forum-lastpost a:hover { color: var(--primary-color); }

/* ==========================================================
   移动端响应式 (首页专属)
   ========================================================== */
@media (max-width: 992px) {
    .forum-list { grid-template-columns: 1fr; }
    .forum-item { border-right: none; }
    .forum-item:last-child { border-bottom: none; }
    .forum-item:nth-last-child(2) { border-bottom: 1px solid var(--border-color); }
}

@media (max-width: 768px) {
    .forum-group {
        border-radius: 0 !important;
        border-left: none !important;
        border-right: none !important;
        margin-left: 0 !important;
        margin-right: 0 !important;
        box-shadow: none !important; 
    }
}