Optional: Install the color theme editor: http://visualstudiogallery.msdn.microsoft.com/366ad100-0003-4c9a-81a8-337d4e7ace05
In the theme editor or Tools > Options > Environment > Fonts and Colors
Search for: ‘HTML Server-Side Script’ to edit the foreground & background of @ and other tags.
Search for: ‘Razor Code’ to edit the background of the Razor code.