403 Forbidden error

sorry if this is a dumb question, not computer saavy. but we use modx at http://www.crossfitsouthbend.com and our website is down with a 403 forbidden error, i was wondering if it is something wrong with the modx, or is it something completely different...i can see IT guys shaking their heads at me right now...sorry!

Have you added any documents (especially the home page) to any document groups?

If not, is there an .htaccess file in the MODx root directory and, if so, has it been modified lately (check the file date)?