Applying css to jquery-loaded HMTL-markup

Applying css to jquery-loaded HMTL-markup

I'm having issues with doing this, although it seems to very doable using the jquery css function (example below):
$('#checkbox').css({ textAlign: "left" });

Specifically, when a user clicks submit, I'm loading an XML document, parsing it and applying HTML mark-up with class styles, and trying to apply the style using the above functionality. Why isn't it working ? Specifically, the ul/li mark-up isn't responding to the css styles.

I greatly appreciate any support/reponse I can get on this. I can provide a url that demonstrates my attempts. - thx