JavaScript: Invert color on all elements of a page

First things first, grab the awesome RGBColor class here.

Here goes:

jsFiddle example

//set up color properties to iterate through
var colorProperties = ['color', 'background-color'];

//iterate through every element in reverse order...
$("*").get().reverse().each(function() {
    var color = null;

    for (var prop in colorProperties) {
        prop = colorProperties[prop];

        //if we can't find this property or it's null, continue
        if (!$(this).css(prop)) continue; 

        //create RGBColor object
        color = new RGBColor($(this).css(prop));

        if (color.ok) { 
            //good to go, let's build up this RGB baby!
            //subtract each color component from 255
            $(this).css(prop, 'rgb(' + (255 - color.r) + ', ' + (255 - color.g) + ', ' + (255 - color.b) + ')');
        }
        color = null; //some cleanup
    }
});

Screenshot:

EDIT: Here’s a bookmarklet you can now copy-paste into your browser (http://jsfiddle.net/F7HqS/1/)

javascript:function load_script(src,callback){var s=document.createElement('script');s.src=src;s.onload=callback;document.getElementsByTagName('head')[0].appendChild(s);}function invertColors(){var colorProperties=['color','background-color'];$('*').each(function(){var color=null;for(var prop in colorProperties){prop=colorProperties[prop];if(!$(this).css(prop))continue;color=new RGBColor($(this).css(prop));if(color.ok){$(this).css(prop,'rgb('+(255-color.r)+','+(255-color.g)+','+(255-color.b)+')');}color=null;}});}load_script('http://www.phpied.com/files/rgbcolor/rgbcolor.js',function(){if(!window.jQuery)load_script('https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js',invertColors);else invertColors();});