function fondNotSelected(num) {
  if (document.getElementById('caseN'+num)){
       document.getElementById('caseN'+num).style.background='#ffffff'; 
  }
}
function fondSelected(num) {
  if (document.getElementById('caseN'+num)){
       document.getElementById('caseN'+num).style.background='#eeeecc'; 
       document.getElementById('caseN'+num).style.cursor='pointer';
  }
}