function fixedEl(){
if (document.all) {
  document.all['black_foreground'].style.position = 'absolute';
  document.all['black_foreground'].style.pixelTop = document.body.scrollTop;
} 
}
function show_photo(adresa) {
  document.getElementById('black_foreground').style.display='block';
  document.getElementById('img_foreground').src=adresa;
  return false;
}