.site-header.site-header-sentinel.fixed {
    background: black;
    opacity: 1;
    top: 0;
  }
  
  .site-header {
  content: "";
  display: table;
  background: black;
  height: 112px;
  position: relative;
  width: 100%;
  z-index: 300;
}

.main-navigation {
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
  float: right;
  max-width: 100%;
}