.fi-duo {
    display: inline-block;
    overflow: hidden;
    position: relative;
    width: calc(1.333333em * 1.2);
    line-height: 0;
    white-space: nowrap;
}

.fi-duo.fis {
    width: calc(1em * 1.2);
}

.fi-duo .fi:nth-child(2) {
    position: absolute;
    left: 50%;
    top: 0;
}

.fi-dnr {
    background-image: url(./4x3/dnr.svg);
    background-position: 50% 50%;
    background-size: cover;
}

.fi-dnr.fis {
    background-image: url(./1x1/dnr.svg);
    background-position: 50% 50%;
    background-size: cover;
}