You'll see that these typography elements don't have classes. That's because on this page, we want to edit the styles after selecting "All H1 Headings" for example, so that it will effect all the elements on the site. To do this, select the H1 below, click where it says "Select a Class or Tag" and select "All H1 Headings" at the bottom of the list.
These are all the sections that are created into 'Symbols' as they are being reused on different pages. Double click on the Symbol to edit it. Any changes made in a Symbol will implement every where else too.