.colorpicker-saturation {
    background-image: url('https://d2x1db8y31vprb.cloudfront.net/images/saturation.png');
}
.colorpicker-hue {
    background-image: url('https://d2x1db8y31vprb.cloudfront.net/images/hue.png');
}
.colorpicker-alpha {
    background-image: url('https://d2x1db8y31vprb.cloudfront.net/images/alpha.png');
    display: none;
}
.colorpicker-color {
    background-image: url('https://d2x1db8y31vprb.cloudfront.net/images/alpha.png');
    background-position: 0 100%;
}