setting css styles usign jQuery

setting css styles usign jQuery

I need to set the css styles to the following elements as follows using
jQuery
#hdr-nav-wrapper ul li:hover a{
background-color:#0294ca;
}
#hdr-nav-wrapper ul a:hover{
background-color:#00aeff;
}
Except that the actual color will have to be dynamic based on whatever the
background color of a div with id of "TestDiv". This site has a theme
engine where users can change colors using a color theme palette. I am
appending a nav bar to the top of the site but I want to have the
background of the nav bar as the same as whatever "TestDiv" currently has.
How do I convert the above css to jQuery with that dynamic logic?