div.wtag-background {
    display: inline-block;
    background-size: contain;
    background-position: 50% 50%;
    background-repeat: no-repeat;
    content: '';
}

div.wtag-background.expand {
    display: block;
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
}

div.wtag-background.cover {
    background-size: cover;
}

div.wtag-background.top {
    background-position: 50% top;
}

div.wtag-background.bottom {
    background-position: 50% bottom;
}

div.wtag-background.left {
    background-position: left 50%;
}

div.wtag-background.right {
    background-position: right 50%;
}