DebateGraph has many different ways of viewing the maps, each useful in its own way. All these Views are available from the Views menu at the top of the screen.
Here are explanations (with short-links for this particular map) of three of the Views:
Outline View: useful for faster navigation on laptops/desktops/tablets:
debategraph.org/irov
Page View: useful for phones (a single-column display with context-sensitive navigation at the foot of the page). A more web-page like experience:
debategraph.org/irpv
Explorer Focus View: a good spatial focus view for laptops/desktops/tablets:
debategraph.org/irev