If you ever need to access the code files for your theme (the CSS, HTML, jQuery etc) you can do so via the Weebly Code editor. This tool lets you edit your theme within weebly rather than editing a file and re-uploading it.
Accessing the raw files for your theme is easy. Just click on the "edit HTML / CSS" button in the "theme" panel of your weebly dashboard.
It is as simple as that.. Once you've clicked this button, the code editor will load up and you'll be able to view and edit all of the files for your theme via the panel on the left. Header types are your html files and everything else will sit underneath the "assets" section