Add this code to the Custom CSS field on the Style tab of your Background Music widget’s settings:
@external {
@media (width <= 500px) {
[class*='VolumeComponent__VolumeControlComponent-sc'] {
display: none;
}
[class*='CloseButton__StyledCloseButtonComponent-sc'] {
margin: 0;
}
[class*='Background__ControlsSecond-sc'] {
margin-left: 20px;
}
}
}