.slider .thumb {
    -fx-background-image: url("/visualiser/images/sun.png");
    -fx-background-size: 25px;
    -fx-pref-height: 25px;
    -fx-pref-width: 25px;
    -fx-background-position: top;
    -fx-background-repeat: no-repeat;
    -fx-focus-color: transparent;
    -fx-background-color: transparent;
}

.slider .track {
    -fx-control-inner-background: dodgerblue;
    -fx-border-color: rgba(30, 144, 255, 0.44);
    -fx-border-radius: 0.25em, 0.25em, 0.166667em;
}