For a full control of your project you can use integrated code editors to edit css and javascript and see a live preview of your changes.
In the css editor you have full control of your project css. css generated by inspector and your custom css will be visible here, you can edit, delete or add custom css all with a live preview in the builder and warning/error message to help you write correct syntax.
In the js editor you can add custom javascript. Any js added here will be executed in the live preview.