The 'Scale' option is almost OK, when speaking of responsive design. E.g. when I set one of the popup styles to scale and width to 0.8 - the popup contact form always fits. The only issue is that I need max-width, so it won't become too wide on wide screens. Such an option would be most beneficial (I tried to do it with CSS but then the modal window loses it's centering).
Any idea? Please help.