Yes, I know. The website doesn't load correctly in the In-Game Web Browser because the In-Game Web Browser is a pile of junk. Many in the Garry's Mod community have discussed the need for it to be updated/replaced, however Garry doesn't want it to happen, for reasons unknown and much to our chagrin.
We apologize for any inconvenience, however this isn't a bug we can fix. Please use a web browser outside of GMod, or even the one present in the Steam Overlay, instead.