Maybe this is due to errors (currently 50) - http://validator.w3.org
1) yes errors where an attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images. they do not play a role on the appearance of the site, but alt for img is better to register;
2) write down the title ;
3) End tag ul seen, but there were open elements. This needs to be corrected;
4) connect one jquery library - now you have it like this:
<script src="http://code.jquery.com/jquery-2.1.1.js"></script> <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script> <script type="text/javascript" src="jquery.min.js"></script>
5) if HTML5 doctype - then why so connect <meta http-equiv = "Content-Type" content = "text / html; charset = utf-8">?