foo {
  filter: progid:DXImageTransform.Microsoft.gradient(GradientType=1,startColorstr=#c0ff3300,endColorstr=#ff000000);
  filter: progid:DXImageTransform.Microsoft.gradient(GradientType=1,startColorstr=#c0ff3300,endColorstr=#ff000001);
}
foo {
  filter: alpha(opacity=20);
  filter: alpha(opacity=20,enabled=true);
  filter: blaznicate(foo=bar,baz=bang bip,bart=#fa4600);
}