You might not need jQuery
No, please no.  If size is an issue for some reason or you want to have no dependencies you can use something like <a href="http://zeptojs.com/" rel="nofollow">http://zeptojs.com/</a> and just embed everything in one minified file. If you do things right only the functions you are actually using will get placed in there as well.<p>Do not reinvent the wheel to solve problems that can't be solved in much cleaner and nicer ways.  Managing dependencies can be annoying, but we all bite the bullet for a very good reason, because reusing solid well tested code is a <i>good</i> thing.