I've mailed them. Got a one-liner as a return:
That was yesterday, after about 12 hours of being offline.

It is also good to notice that sometimes i can get through to the site... about once an hour or so, for few seconds only, before it becomes unresponsive again. Also PINGs won't work much either (they usually do work, even if their server has its famous Bad gate "nginx" apology). Seems likely they are indeed under attack. This has happened before, few months ago.