.identifiant{opacity:0.0}
<div style="width:300px; font-size:12px; border:1px solid red; background-color:blue; opacity:0.0; color:#ffffff">
opacity opacity opacity opacity opacity opacity <br>opacity opacity opacity opacity
</div>
.identifiant{opacity:0.5}
<div style="width:300px; font-size:12px; border:1px solid red; background-color:blue; opacity:0.5; color:#ffffff">
opacity opacity opacity opacity opacity opacity <br>opacity opacity opacity opacity
</div>
.identifiant{opacity:1}
<div style="width:300px; font-size:12px; border:1px solid red; background-color:blue; opacity:1; color:#ffffff">
opacity opacity opacity opacity opacity opacity <br>opacity opacity opacity opacity
</div>
.identifiant{opacity:0.0}
