It is actually very easy to copy some HTML from a legit site for the purposes of a phishing campaign. I don't think improving the web design will help mitigate

It is actually very easy to copy some HTML from a legit site for the purposes of a phishing campaign. I don't think improving the web design will help mitigate that, unless you mean moving all rendering to a canvas element and implementing all of the functionality of the site on some obfuscated VM.