Left-hand nav on developer hub template is unusable

[dhcole]

Reported by @mogul:

Reproduction steps in Gherkin-ish test code:

Scenario: The left-hand navigation should be usable without scrolling on a short page (but it is covered up by the site footer on short pages)

When I look at the developer hub microsite example,
and I click on "API calls" in the left-hand navigation,
then I should be able to see a link to the "Contribute" page in the left-hand navigation
but I cannot get to all pages listed in the left-hand navigation

Scenario: The left-hand navigation should be usable after fully scrolling on a long page, (but it is covered up by the site footer when you scroll all the way down)

When I look at the developer hub microsite example,
and I click on "Overview" in the left-hand navigation,
and I scroll to the bottom of the page
then I should be able to see a link to the "Contribute" page in the left-hand navigation
but I cannot get to all pages listed in the left-hand navigation