javascript:var sca = 1.01; var div = document.getElementsByClassName('btn-danger')[0]; var loop = setInterval(function() { div.style.webkitTransform = 'scaleX('+sca+')'; div.style.mozTransform = 'scaleX('+sca+')'; div.style.msTransform = 'scaleX('+sca+')'; div.style.oTransform = 'scaleX('+sca+')'; div.style.transform = 'scaleX('+sca+')'; sca += 0.01; }, 25);