Logo Upload button not working!!

I am new to this and I really dont have any idea about the codings! My apologies for that. I have created a site but the problem is that I am not able to upload my logo when I click the upload logo button nothing happens!! The same happens with header image upload also. However I am able to add files to media.
I tried reading almost all posts related to logo issue but nothing seems like a solution!! below is my website
www. thunikkada. com