(function(){
  let hour = new Date().getHours();
  let greeting;
  if (hour < 20) 
  {
    --text-color: #E6FF00;
    document.documentElement.style.setProperty('--text-color', '#E6FF00');
  } 
  else 
  {
    --text-color: #00A599;
    document.documentElement.style.setProperty('--text-color', '#00A599');
  }
})();