text: var emailText = document.getElementById('email');
  var passwordText = document.getElementById('password');
  
  var emailErr = document.getElementById('emailErr');
  var passwordErr = document.getElementById('passwordErr');
  
  function onClick(){
      var flag = true;
      
     if (!emailText.value.trim()){
         emailErr.style.visibility = "visible";
         flag = false;
     }
     else
         emailErr.style.visibility = "hidden";
      
      if (!passwordText.value.trim()){
          passwordErr.style.visibility = "visible";
          flag = false;
      }
      else
          passwordErr.style.visibility = "hidden";
      
      return flag;
          
  }