.posts-container{display:flex;flex-wrap:wrap;margin:-15px}.col-md-3{flex:0 0 calc(25% - 30px);max-width:calc(25% - 30px);box-sizing:border-box;padding:15px}@media (max-width:768px){.col-md-3{flex:0 0 100%;max-width:100%}}