function checkForm() {
  var selectedId = document.getElementById('subject').value; 

  var instRow = document.getElementById(selectedId);
  
  if ( instRow ) {
     hideSpecialInstructions();
     instRow.style.display = '';
     disableForm();
  } 
  else {
    enableForm();
    hideSpecialInstructions();
  }
  
}

function enableForm() {
  enableFormField('storeAddress');
  enableFormField('name');
  enableFormField('email');
  enableFormField('phone');
  enableFormField('comments');
  enableFormField('submit');
}

function enableFormField(fieldName) {
  var field = document.getElementById(fieldName);
  if ( field ) {
    field.disabled = false;
    field.style.backgroundColor = '';
  }
}

function disableForm() {
  disableFormField('storeAddress');
  disableFormField('name');
  disableFormField('email');
  disableFormField('phone');
  disableFormField('comments');
  disableFormField('submit');
}

function disableFormField(fieldName) {
  var field = document.getElementById(fieldName);
  if ( field ) {
    field.disabled = true;
    field.style.backgroundColor = '#D4D0C8';
  }
}

function hideSpecialInstructions() {
  document.getElementById('0-7').style.display = 'none';
}