Any code examples to show how this is done?
I tried adding a class and id to the object and defining a font-size before creating this post without any joy. [Class is an undocumented property in your API documentation]
<ComboBox Class=”vcs-combo”  Id=”idIlluminant” …
and in style.css
.vcs-combo {
font-size: smaller;
#idIlluminant {
font-size: xx-small;
ComboBox {
font-size: x-small;
No joy with any of them.