The is no web interface for MB. If all you want to do is control MB (i.e. listen to music and not do any tagging management) look for the Android Remote plugin or the iTunes Remote plugin. I've never used either so I can't vouch for them. But threads exist in the plugins section.
Another option is to use Subsonic, or one of it's many forks. By setting up Subsonic service on a PC, you can then listen to music from anywhere there is an internet connection.