function makeVisible() {

  document.getElementById("ones_text").style.display = "block";

}



function changeAmount() {

  if (document.getElementById('amount').disabled == false) {

    var elem = document.getElementById("daholder");

    elem.innerHTML = "";



    var otherAmount = '<input type="text" name="amount" id="amount" style="margin-left: 10px; width: 80px" />';

    elem.innerHTML = otherAmount;



    var otherElem = document.getElementById("other");

    otherElem.innerHTML = "";

  } else {

    alert ('Please choose your country first.');

  }

}



function defineCurrency(currCode) {

  if (currCode == '') { currCode = 'USD' };

  document.getElementById('currency_text').innerHTML = currCode;

  document.getElementById('currency_code').value = currCode;

  document.getElementById('amount').disabled = false;

}



function checkCustAmount() {

  var custAmount = document.getElementById('amount').value;

  var noAction = document.getElementById('amount');

  var currCode = document.getElementById('currency_text').innerHTML;

  if (custAmount == '' || custAmount < 20 || isNaN(custAmount) == true || noAction.disabled == true) {

    alert ('The amount need to be at least 20 ' + currCode + ' or more.');

    return false;

  }

}