.custom-mask-img-1 {
    -webkit-mask-image: url(../images/demo/mask-image-1.png);
    mask-image: url(../images/demo/mask-image-1.png);
    -webkit-mask-repeat: no-repeat;
                    mask-repeat: no-repeat;
    -webkit-mask-size: 100%;
                    mask-size: 100%;
    -webkit-mask-position: center;
                    mask-position: center;
}

.custom-mask-img-2 {
    -webkit-mask-image: url(../images/demo/mask-image-2.png);
    mask-image: url(../images/demo/mask-image-2.png);
}

.custom-mask-img-3 {
    -webkit-mask-image: url(../images/demo/mask-image-3.png);
    mask-image: url(../images/demo/mask-image-3.png);
}

.custom-mask-img-4 {
    -webkit-mask-image: url(../images/demo/mask-image-4.png);
    mask-image: url(../images/demo/mask-image-4.png);
}