JavaScript elector type issue and 'Ajax SEO' defined as variable

JavaScript elector type issue
'Ajax SEO' defined as common PHP variable
Simplified markup without <b>
AJAX changed to Ajax
Revert "JavaScript elector type issue and 'Ajax SEO' defined as variable"

This reverts commit 0a26f0f86f29a2fbcad42af3ba7558514e9e4af5.
JavaScript selector type issue and "Ajax SEO" defined as variable
Improved typography, semantic and fixed .selected navigation item visibility