#slider_blocks {
  zoom: 1; position:relative; float:left; width:100%
}

@media all and (-ms-high-contrast: none), (-ms-high-contrast: active) {
  header {
    background: #1551a1;
  }
  #slider_blocks {
    position: relative;
    margin-top: 0;
    overflow: hidden;
  }
}