function check_send()
{
    var name_reed = document.getElementById('name');
    var mail_reed = document.getElementById('mail');
    var info_reed = document.getElementById('info');
    var btn = document.getElementById('btn');
    if ((info_reed.value!= '') && (name_reed.value!= '') && (mail_reed.value!= '')) { btn.disabled = false; } else { btn.disabled = true; }
}



function myFunc (x)
{
var t = document.getElementById (x);
if (OBJ != t)
   {
   t.style.display = 'none'; OBJ = null;
   if (OBJ) OBJ.style.display = 'none';
   t.style.display = 'none';
   OBJ = t;
   }
}


function MyGroup(x) {  
    var objSel = document.getElementById("sphera");
    var sphera_reed=objSel.options[objSel.selectedIndex].value;

if ((sphera_reed=="seo") || (sphera_reed=="design"))  {
document.getElementById("CM1").style.display="block";
document.getElementById("CM2").style.display="block";
document.getElementById("CM3").style.display="none";
document.getElementById("CM4").style.display="none";
}

if ((sphera_reed=="developers") || (sphera_reed=="seoshniki"))
{
document.getElementById("CM1").style.display="none";
document.getElementById("CM2").style.display="none";
document.getElementById("CM3").style.display="block";
document.getElementById("CM4").style.display="block";
}
}