function swapHero(newImg) {
	document.getElementById('heroImage').src = newImg;
}

function showHero(imgID) {
	hideHeroImages();
	document.getElementById(imgID).style.display = "block";
}

function hideHeroImages() {
	// Loop through all images, check if they contain the class 'stroke_hero' - if so, hide them
 var imgs,i;
 imgs = document.getElementsByTagName('img');
 for(i=0;i<imgs.length;i++) {
  if(/stroke_hero/.test(imgs[i].className)) {
		imgs[i].style.display = 'none';
  }
 }
}