function effacerbloc(bloc)     
{     
if(document.getElementById)        
 document.getElementById(bloc).style.visibility = 'hidden' 
 document.getElementById(bloc).style.top = '-1000px'
 document.getElementById(bloc).style.left = '-1000px'
  } 
  function afficherbloc(bloc)   
{     
if(document.getElementById)         
document.getElementById(bloc).style.visibility = 'visible'
document.getElementById(bloc).style.top = '105px'
 document.getElementById(bloc).style.left = '148px'
} 

/*function tout_effacer()
{
if(document.getElementById)         
document.getElementById('boite').style.visibility = 'hidden'
document.getElementById('boite').style.top = '-600px'
 document.getElementById('boite').style.left = '-600px'
          
document.getElementById('boiteformule').style.visibility = 'hidden'
document.getElementById('boiteformule').style.top = '-600px'
document.getElementById('boiteformule').style.left = '-600px'

document.getElementById('boiteformuletarif').style.visibility = 'hidden'
document.getElementById('boiteformuletarif').style.top = '-600px'
document.getElementById('boiteformuletarif').style.left = '-600px'

document.getElementById('boitejysuis').style.visibility = 'hidden'
document.getElementById('boitejysuis').style.top = '-600px'
document.getElementById('boitejysuis').style.left = '-600px'

document.getElementById('boitepresence').style.visibility = 'hidden'
document.getElementById('boitepresence').style.top = '-600px'
document.getElementById('boitepresence').style.left = '-600px'

document.getElementById('boiteactive').style.visibility = 'hidden'
document.getElementById('boiteactive').style.top = '-600px'
document.getElementById('boiteactive').style.left = '-600px'

document.getElementById('boitemetier').style.visibility = 'hidden'
document.getElementById('boitemetier').style.top = '-600px'
document.getElementById('boitemetier').style.left = '-600px'

document.getElementById('boitecommerce').style.visibility = 'hidden'
document.getElementById('boitecommerce').style.top = '-600px'
document.getElementById('boitecommerce').style.left = '-600px'

document.getElementById('boitepresta').style.visibility = 'hidden'
document.getElementById('boitepresta').style.top = '-600px'
document.getElementById('boitepresta').style.left = '-600px'

document.getElementById('boitepresent').style.visibility = 'hidden'
document.getElementById('boitepresent').style.top = '-600px'
document.getElementById('boitepresent').style.left = '-600px'

document.getElementById('boiteprincipes').style.visibility = 'hidden'
document.getElementById('boiteprincipes').style.top = '-600px'
document.getElementById('boiteprincipes').style.left = '-600px'

document.getElementById('boitemethodes').style.visibility = 'hidden'
document.getElementById('boitemethodes').style.top = '-600px'
document.getElementById('boitemethodes').style.left = '-600px'

document.getElementById('boitereferences').style.visibility = 'hidden'
document.getElementById('boitereferences').style.top = '-600px'
document.getElementById('boitereferences').style.left = '-600px'

document.getElementById('boitecontact').style.visibility = 'hidden'
document.getElementById('boitecontact').style.top = '-600px'
document.getElementById('boitecontact').style.left = '-600px'
}

 function afficherboite()
{     
if(document.getElementById)         
document.getElementById('boite').style.visibility = 'visible'
document.getElementById('boite').style.top = '233px'
 document.getElementById('boite').style.left = '219px'
} */