Top Navbar: Remove the org name on mobile

[kasugaijin]

The top navbar in mobile does not look great with the logo and name split like this.

Please update the navbar to achieve the following:

• retain the existing behaviour for screen widths where the navbar remains a single row (above ~482px)
• redesign for screens that currently cause it to collapse into two rows (~482px) so that the hamburger and two buttons move to the left, and we show just the logo (no org name) on the right side. This may require a new mobile navbar partial that we show on a certain screen width and below (ideally, stick to the bootstrap breakpoints rather than implement custom CSS)