Everyone knows client-side applications are built with JavaScript. Right? JavaScript ties the application together, but a considerable amount of most applications deals with markup and presentation. As much as they affect JavaScript, state, event handling, and default browser behaviour also impact HTML and CSS in the choices we make, optimisations we can take advantage of, and the architecture of our applications as a whole. And the HTML and CSS that make up the structure of our applications need to be managed just as much as our JavaScript does. We’ll talk about how HTML and CSS fit into the the big picture and how to take greater advantage of them in a context where we frequently consider them last.