[UIXPRESS] Synchronize Color Variables With Custom CSS

Thanks again for this amazing plugin!

There is one crucial problem: Many plugins don’t recognize the uiXpress colors, so styling these plugins is quick and easy to do with the great custom css feature in uiXpress. But styling all the elements with the uiXpress color variables like “--uix-base-900” inside the custom css editor does not work when switching uiXpress to light mode. Everything I styled using the variables is still dark. So apparently uiXpress is not synching the custom styles with the light mode, which defeats the purpose of styling with the uix variables, because nothing matches up after switching between light modes. This is a very crucial problem and it would be awesome if this could be fixed :)