#sidebar_ad_1 {
  float: left;
  margin-top: 130px;
}

#sidebar_ad_2 {
  float: right;
  margin-top: 130px;
}

#header_ad_1 {
  margin-left: 100px; padding-top: 15px;
}

#footer_ad_1 {
  float: left;
  margin-top: 10px;
  margin-left: 50px;
}

#footer_ad_2 {
  float: right;
  margin-top: 10px;
  margin-right: 50px;
}