var btnObjs=document.getElementsByTagName("input"); // this will return all the input objects
for (i=0; i<btnObjs.length; i++) {
  var btnObj=btnObjs[i];
  if (btnObj.className == "btn-continue") { //find the continue button
    //start attaching onmouse over and onmouse out events
    attachHover(btnObj, "btn-continue", "btn-continue-hover");
  } else if (btnObj.className == "btn-back") {
    //start attaching onmouse over and onmouse out events
    attachHover(btnObj, "btn-back", "btn-back-hover");
  } else if (btnObj.className == "btn-support") {
    //start attaching onmouse over and onmouse out events
    attachHover(btnObj, "btn-support", "btn-support-hover");
  }
  else if (btnObj.className == "btn-about") {
    //start attaching onmouse over and onmouse out events
    attachHover(btnObj, "btn-about", "btn-about-hover");
  }
  else if (btnObj.className == "btn-disclaimer") {
    //start attaching onmouse over and onmouse out events
    attachHover(btnObj, "btn-disclaimer", "btn-disclaimer-hover");
  }
}

function attachHover(obj, css_out, css_over) {
    //start attaching onmouse over and onmouse out events
    if (obj.addEventListener) { //NS, Firefox event attach
        obj.addEventListener("mouseover", function(e){
            e.target.setAttribute("className", css_over); //IE
            e.target.setAttribute("class", css_over); //NS, Firefox
        }, false);
        obj.addEventListener("mouseout", function(e){
            e.target.setAttribute("className", css_out); //IE
            e.target.setAttribute("class", css_out); //NS, Firefox
        }, false);
    } else { //IE only event attach
        obj.attachEvent("onmouseover", function(e){
            e.srcElement.setAttribute("className", css_over); //IE
            e.srcElement.setAttribute("class", css_over); //NS, Firefox
        });
        obj.attachEvent("onmouseout", function(e){
            e.srcElement.setAttribute("className", css_out); //IE
            e.srcElement.setAttribute("class", css_out); //NS, Firefox
        });
    }
}