.post-grid-tabs {
    display: flex;
    flex-direction: column;
}

.tab-titles {
    display: flex;
    list-style-type: none;
    margin: 0;
    padding: 0;
}

.tab-titles li {
    margin-right: 10px;
}

.tab-titles a {
    display: block;
    padding: 10px 20px;
    background: #f0f0f0;
    text-decoration: none;
    color: #333;
    border-radius: 3px;
}

.tab-titles a.active {
    background: #0073aa;
    color: #fff;
}

#post-grid-content {
    margin-top: 20px;
}

.post-grid {
    display: flex;
    flex-wrap: wrap;
}

.post-item {
    width: 30%;
    margin-right: 3.333%;
    margin-bottom: 20px;
}

.post-item h2 {
    font-size: 18px;
    margin: 0 0 10px;
}

#post-grid-content p {
    text-align: center;
}