// create a bookmark and use this code as the URL, you can now toggle the css on/off // thanks+credit: https://dev.to/gajus/my-favorite-css-hack-32g3 (function() { const element = document.querySelector('#test-layout-styles'); if (element) { document.head.removeChild(element); } else { const style = document.createElement('style'); style.id = 'test-layout-styles'; style.innerHTML = ` * { background-color: rgba(255,0,0,.2); } * * { background-color: rgba(255,0,255,.2); } * * * { background-color: rgba(0,255,255,.2); } * * * * { background-color: rgba(255,255,0,.2); } * * * * * { background-color: rgba(0,255,0,.2); } * * * * * * { background-color: rgba(0,0,255,.2); } * * * * * * * { background-color: rgba(255,0,0,.2); } * * * * * * * * { background-color: rgba(255,255,0,.2); } * * * * * * * * * { background-color: rgba(0,255,255,.2); } `; document.head.appendChild(style); } })();