ACE3/docs/src_old/scss/ui/_icons.scss

.icon {
    position: relative;
    top: 1px;
    display: inline-block;
    width: 16px;
    height: 16px;

    &-color {
        border: 1px solid #aaa;

        &-white {
            background-color: #fff;
        }
        &-black {
            background-color: #000;
        }
        &-red {
            background-color: $ace-primary-color;
        }
    }

}