Looking for a tool to store guidelines for the team

I'm looking for a tool where the team can store UX guidelines. I'm looking for something wiki-like, but a little bit more inspiring :)

The kind of guidelines we need to store is basically spacing, colors, font size and so on (with images and text). We need it to be structured since it will be a lot of information.

Target audience would of course be the UX team, as well as the UI development teams.

Does any of you have any ideas?