Change highlight colour to deep magenta.

Use this for h1s and for the page-header underline.
Increase font size for h1s.

Bump it up to 44px from 36px.
Override brand colour in navbar.

Use the new highlight colour, and define a darker colour (by factor of
0.62) for focus and hover states.
Add CGO logo to navbar.

Display a small version of the CGO logo in the site's navbar in the
brand area. Shrink the brand text down from "Cambridge Graduate
Orchestra" to "CGO", and add the logo to the left of the brand text so
it is nicely padded within the navbar and displays in line with the left
border of the body content.
Add CGO logo original image file.

Add the logo to the repository for future reference.
Fix the navbar brand's padding.

Pad it to 15px on both sides to ensure there's sufficient padding
between the brand and the first navbar menu item. This is the default
Bootstrap value for padding of this item, and so blends in nicely. It
also means the nasty margin-left hack I'd put in on the brand image
(logo) can be removed!
Add the background image at different resolutions.

Include the appropriate background image by screen width, using a set of
media queries.

I'm not 100% sure this is correct, or that I've got the images quite
right: at the moment, the images are sized to the minimum dimensions
required (e.g. 992px wide for screen-md), but I think this should be
changed to the maximum dimensions (i.e. the minimum dimensions for the
next size up, so 1200px wide for screen-md) to avoid artefacts appearing
in the background image.