When ever you ever have to inject HTML into an unknown page you have to battle with all the page styles messing with your own content. This happens a lot when building bookmarklets like my recent RSVP Reader. In the past you had to manually assign values for all the CSS properties that could have been set by the page. Since then then initial CSS property was added we can perform this reset automatically. The following is a function that resets all CSS properties for a given DOM node.

function resetStyles(node) {
    if(!node)
        console.error('node was invalid\: ' + node);
    /* iterate over the DOM nodes style properties and set them to initial */
    var props = window.getComputedStyle(node, null);
    for(var i=0, len=props.length ; i < len ; i++) {
        node.style[props] = 'initial';
    }
};