Navigation and Optimal Viewing
Navigation is easiest achieved by clicking on a picture.
Within a series, arrows allow to go back and forth.
I recommend returning one level up in the menu by using (eventually repeatedly) the "delete" key.
On most browsers, this is also possible with the arrow keys, in conjunction with a modifier key,
"Ctrl" for Windows and the "Apple" key for an Apple.
It is also possible to use the browser's "back"-button.
Some browser allow to view the site in full-screen mode.
In Chrome this is achieved by clicking on the tool-icon.