function showBorder(divid) {
    document.getElementById("error").style.display = "block";
    document.getElementById(divid).style.outline = "red solid thin";
}

function hideBorder(divid) {
      document.getElementById(divid).style.outline = "none";
}
    
function validateForm() {
    if(document.frm.name.value == "") {
        showBorder("name");
    } else { hideBorder("name"); }
    
    if(document.frm.email.value == "") {
        showBorder("email");
    } else { hideBorder("email"); }
    
    if(document.frm.feedback.value == "") {
        showBorder("feedback");
    } else { hideBorder("feedback"); }
    
    if(document.frm.name.value == "" || document.frm.email.value == "" || document.frm.feedback.value == "") {
        return false;
    }
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    }
  }
}

addLoadEvent(function() {
    document.frm.reset();
})