When doing growth driven design pages it is often difficult and time consuming to rework their entire structure. This script allows you to remove a css file using JS to remove all the styling in teh file. Not the best way to do it, but a nice hacky way to make it happen

remove-loaded-css-file-from-page.js

var stylesheetUrl = 'http://cdn2.hubspot.net/hub/281759/hub_generated/style_manager/1400729881665/custom/page/css/brpt-dusk.min.css';
var extraStylesheetUrl = 'http://cdn2.hubspot.net/hub/281759/hub_generated/style_manager/1420258246895/custom/styles/default/hs_default_custom_style.min.css';
for ( i=0; i<document.styleSheets.length; i++) {
    var url = document.styleSheets.item(i).href;
    console.log(url)
    if ( url == stylesheetUrl || url == extraStylesheetUrl ) {  
    void(document.styleSheets.item(i).disabled=true);
    }
}