each item in Oracle Apex got 3 "CSS Classes" attributes. One in "Layout" section, one in "Appearance", and the other in "Advanced". I've tried to use them all, and can't see any difference. Is there one? Thanks
Each attribute adds the class to a different level in DOM.
For example, if you want the class you added to affect the whole row of the item then you use layout. If you want the class to affect only the input element(my example item type is a text field, so I have an input tag in HTML Dom), then you use the advanced section.