Has anyone ever designed a visual editor or IDE where the syntactic and semantic elements were differentiated using font SIZE as well as the usual colouring and

Has anyone ever designed a visual editor or IDE where the syntactic and semantic elements were differentiated using font SIZE as well as the usual colouring and face variation (bold, italic, underline) we normally get? I could imagine having class names in a larger, heading type font size, for example. Code folding could be used, with attributes like access modifiers aligned underneath. Code blocks could be displayed as actual boxes, with borders and fills?