.header-top {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 90;
  transition: background-color .25s ease, box-shadow .25s ease;
}

/* give back the 67px the fixed bar removed from the flow (JS refines this) */
.site-header .js-background-type {
  padding-top: 67px;
}

/* background only after scrolling, matched to each page's colour scheme */
html.header-stuck .dark-background .header-top {
  background-color: #000000;
  background-color: rgba(0, 0, 0, .92);
}

html.header-stuck .light-background .header-top {
  background-color: #ffffff;
  background-color: rgba(255, 255, 255, .96);
}

html.header-stuck .header-top {
  box-shadow: 0 1px 6px rgba(0, 0, 0, .12);
}

/* leave the Voog editor alone */
html.editmode .header-top {
  position: static;
}

html.editmode .site-header .js-background-type {
  padding-top: 0;
}

/* theme sets perspective:1000px here, which makes .site-container the
   containing block for fixed children and kills the sticky bar */
.site-container {
  -webkit-perspective: none;
  perspective: none;
}