a {
text-decoration: none;
color: #636668;
}
.category-fl {
    width: 1400px;
    margin-left: auto;
    margin-right: auto;
}
.category-content { display: none; padding: 20px; border: 1px solid #ccc; }
    .category-content.active { display: block; }
    .category-tab { padding: 8px 16px; margin: 5px; cursor: pointer; }
    .category-tab.active { background: #007bff; color: white; }