Header and navigation layout broken on iPad (768px wide)

[adamwoodnz]

The changes introduced when moving to the accessible locale switcher have broken the iPad layout at exactly 768px wide:

1. There is too much padding on the navigation bar (should be 20px on either side)
2. The site branding text 'WordPress celebrates twenty years' isn't visible
3. Both the page navigation menu and locale switcher layouts are broken when open

Default	Navigation active	Locale switcher active