VS Code is essentially a browser app based on Typescript(Javascript) and html. You can even open the chrome dev tools in VS Code (Help -> Toggle Dev Tools) and

VS Code is essentially a browser app based on Typescript(Javascript) and html. You can even open the chrome dev tools in VS Code (Help -> Toggle Dev Tools) and inspect the html and javascript of VS code. You can also go so far as to change the CSS and html of vs code in the dev tools. Try using the element picker (top left icon in the dev tools) to select an element in vs code, and you'll see that each line of code is a div and each token is a span that is syntax highlighted by CSS classes.