If the iframe
loads a page on your own domain, and you want to statically change the iframe
s styles, you could just change the style rules in the CSS file, this is what @Justin808 is referring to.
However if you want to dynamically change the styles, and the iframe
loads a page on your own domain, you could do this using jQuery:
$("iframe").contents().find("element-selector").css("border-color", "blue");
If the iframe
loads a page on another domain, you're out of luck, follow this link, where you can read up a bit on why that doesn't work.
If you're using HTML5, you can use postMessage to communicate between the page and the iframe
.
@crdunst's solution will work if you have "editing access" to the page inside the iframe
so that you can edit it to understand the parameters which are passed to it, and then make it act upon those parameters. It is not as dynamic as using jQuery as it only allows you to change styles by reloading the page inside the iframe
and passing it another set of parameters.