Resize title based on device

Been a while since I used Wappler and now back working on my site.
I am probably overlooking something.
Basically have a background image with text, all fine.
How do I resize the title based on the device, as the text doesn’t seem responsive?
Ideally, I want text with different absolute positions and sizes based on xs, large etc.
Apologies if I have missed something silly here, just cant seem to get it working.