in jquery u can say: $('#name id')
u can write the same thing only with less code, JQuery does it for u.
u have several options to implement JQuery in to your project.
u can download JQuery download
then u have to put it in a folder and link to it from your html file.
the link u put it in the head section of your html
the disadvantage is that u have to be aware that u keep the library up to date.
the second way is to click on download button on the site.
copy the url from your url field.
put this in the head of your html file this way u have JQuery always up to date
u can not put jquery in your CSS stylesheet. CSS stylesheet is for your layout. learn more about css
the difference is also visible in when u link to the files from your html file. (look at the type tag and the beginning one is script one is link)
<link type="text/css" rel="stylesheet" href="yourstyle.css">
if it doesnt run in ie try this link
hope its a bit cear now