div.content_2_by_2{
    float: left;
    margin:50px;
}
a.img_link{
    display: inline-block;
    position: relative;
    z-index: 1;
    padding: 0.5em;
    margin: -0.5em;
}
footer.blog {
    background-color: #efefef;
    flex: 0 0 50px;
    margin-top: auto;
}
img{
    width: 100%;
    height: auto;
}