If I use an HTML template like in the sample "TMSWeb_HTMLTemplate", how would I change the color of a Weblabel referenced by element ID when the user clicks on a button.
For HTML elements referenced by control, the logic is that style is controlled by HTML, the data is coming from the Pascal class. You can of course access the HTML element (and its style) directly from Pascal code.
You could do something like weblabel.ElementHandle.style.setProperty('color','red');