Inspected on Google Chrome 52
I'm very impressed actually with the design. I do however find it a significant problem that the text is not all that different in color from the background it is against. Your colors between the text and the background need to contrast a bit more in order to make it easier to read. I'd recommend making the text a bit brighter. Be careful using these colors too when it comes to control elements. It gives me the impression everything is disabled when it really isn't, which can be bad for UX.
You need a landing page. The first thing users should see when visiting a website is brief information about the website and what you provide to others, as well as calls to action (eg. big "Register for free" buttons) on the landing page. Instead, I simply get latest threads, members, popular forums, and so on... I have no idea what the website is on first impression.
I like the responsiveness of the site, but it needs improvement. Here's what happens on the members page when I shrink my width to the smallest possible:
Either this needs fixed, or you need to add in CSS to prevent browsers from using a screen size smaller than a certain width (I wouldn't recommend going that route though).
Same thing happens for your footer:
Your media rendering elements are also not responsive:
I would try making the entirety of the menu clickable:
If, say, I click within the "Members" menu box, but I don't actually click the word "members", it doesn't do anything... I have to click the word "members". It would be more intuitive to make the whole box clickable especially for mobile users.
You have a little problem with your search bar... the magnifying glass is on another line when it should be alongsize the search text box:
Restricting the ability to view warning logs is a bad idea for moderation:
I can't tell if this is own warning or warnings for others, so I'm pitching both cases.
Users, regardless of their account rank, status, donations, and so on... should be able to read their own warning logs with their reason (also typo... 'along' with 'their' reason). If they can't, they won't know what they did wrong, which means extremely poor publicity and trust for you.
If this is a privilege to view other members' detailed warning logs, then this should be zapped completely and only given to staff. It is also poor moderation to allow non-staff any ability to view the discipline of other members. Members can use that to the disadvantage of other members to attack them and judge them.
---
Other than these points above, great start and I wish you luck!