How to customize in style properties-panel

Hello everyone, i would like to style some fields in the properties-panel and change their color when it is in Read Only Mode.I attached some styling in it but when i click on a task even when the styling class has the same name doesn’t save the changes.

What does that mean? How are you overriding the styles?

I get the element class by
const propertiesPanelInput = document.getElementById(“bio-properties-panel-input”) and then i add
this.modeler.attach( propertiesPanelInput)
and then setAttribute(‘style’,‘background-color:red’)