Startup Idea: Advanced Web-Design Prototyping Software

Startup idea to develop an innovative web-design prototyping tool that provides accurate code alongside visual output. This software aims to replace existing WYSIWYG editors that are known for messy code generation, thereby satisfying the needs of professional web designers.

My main job is web design and there are tons of programs that do wsiwyg or What You See is What You Get editors. These output terrible code and/or just the equivalent of training wheels to a two wheeler bike. You shouldn't use this on an actual website and probably shouldn't show clients in terms of prototyping either. I think if there was a way to make a proper prototyping software that didn't spit out inaccurate code would be great.