the current webchat integration looks cheap, i did try the online styler but still, for the capablity of the looks are too cheap and diffrecut to get it right on all window sizes and phones like other chat do, what are the alternatives to have the bot inteact with users on web and mobile web in an elgant modern way?

You can provide your custom css sheet and set the box size and all the coloura there. You can also change the dimensions for mobile/desktop users in css

do i need to learn complex css for that?

if you want additional customizability beyond our current styling options then custom CSS is your best way to do that, yeah!