How about a HTML & CSS & Flex and Grid Layout tool for responsive webpages?
With @media (min-width: queries
Also a menu button creator.
Example 3 columns across and 4 rows and type in the details with the correct media query.
Flex and Grid Layout tool
Re: Flex and Grid Layout tool
You might be able to integrate something like https://grid.layoutit.com/ (https://github.com/Leniolabs/layoutit-grid) in a separate window. And then pass back the result to Webuilder and insert the code.
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