var coverAll = document.getElementById('cover');
  var coverOp = 1;
  function fadeCover(){ 
    to_fadeCoverAll = setInterval("fadeCoverAll()", 20);
  }
  //=====================================================
  //=====================================================
  function fadeCoverAll(){
    coverOp = coverOp<0.1 ? 0 : coverOp-0.1;

    coverAll.style.opacity = coverOp;
    coverAll.style.filter = 'alpha(opacity = ' + coverOp*100 + ')';

    if(coverOp<0.1){
      clearInterval(to_fadeCoverAll);
      coverAll.style.visibility="hidden";
    }
  }