Heure sur site internet

<script type="text/javascript"> 
var elemDate; 

function afficherDate() { 
 var cDate = new Date(); 
 var heure = cDate.getHours(); 
 var minute = cDate.getMinutes(); 
 var seconde = cDate.getSeconds(); 
  
 elemDate.innerHTML = heure+':'+minute+':'+seconde; 
} 

window.onload = function() { 
 elemDate = document.getElementById('date'); 
 afficherDate(); 
 setInterval(function() { 
  afficherDate(); 
 }, 1000); 
}; 
</script>

<span id="date"></span>

<?php echo date('H:i:s'); ?>