/* AI最新動向ヘッダー用スタイル（papers用） */

/* ヘッダー */
.ai-header {
    background: linear-gradient(135deg, #1a73e8 0%, #1557b0 100%);
    color: #fff;
    padding: 0.8rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.ai-header .category-icon {
    flex-shrink: 0;
}

.ai-header .ai-icon {
    filter: brightness(0) invert(1);
}

.ai-header .site-title {
    margin: 0;
    font-size: 1.5rem;
    font-weight: 700;
    border-bottom: none;
    padding-bottom: 0;
}

.ai-header .header-title-link {
    color: #fff;
    text-decoration: none;
}

.ai-header .header-title-link:hover {
    text-decoration: underline;
}

/* サブナビゲーション */
.sub-navigation {
    background: #f8f9fa;
    border-bottom: 1px solid #e0e0e0;
    padding: 0.5rem 1rem;
}

.sub-navigation .nav-container {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    max-width: 1200px;
    margin: 0 auto;
}

.sub-navigation a {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.4rem 0.8rem;
    color: #333;
    text-decoration: none;
    font-size: 0.85rem;
    border-radius: 4px;
    transition: background-color 0.2s;
}

.sub-navigation a:hover {
    background: #e8e8e8;
}

.sub-navigation a.active {
    background: #1a73e8;
    color: #fff;
}

.sub-navigation a i {
    font-size: 0.9rem;
}

/* 2カラムレイアウト調整 */
.container-with-sidebar {
    margin-top: 0;
}

/* モバイル対応 */
@media (max-width: 768px) {
    .ai-header {
        padding: 0.6rem 1rem;
    }
    
    .ai-header .site-title {
        font-size: 1.2rem;
    }
    
    .ai-header .ai-icon {
        width: 32px !important;
        height: 32px !important;
    }
    
    .sub-navigation {
        padding: 0.4rem 0.5rem;
        overflow-x: auto;
    }
    
    .sub-navigation .nav-container {
        flex-wrap: nowrap;
        gap: 0.3rem;
    }
    
    .sub-navigation a {
        padding: 0.3rem 0.5rem;
        font-size: 0.75rem;
        white-space: nowrap;
    }
    
    .sub-navigation a span {
        display: none;
    }
    
    .sub-navigation a i {
        font-size: 1rem;
    }
}