body {
  background-image:
    url(assets/images/white-gradient-overlay.png),
    url(assets/images/brown-polka-dots.png);
  background-position: center, center;
  background-size: cover, 26%;
  min-height: 100vh;
}
.header {
  position: absolute;
}
.header img {
  height: auto;
  width: 50%;
}
.top-header {
  height: auto;
  left: 0;
  position: fixed;
  top: 0;
  width: 100%;
  z-index: -10;
}
.top-header img {
  display: block;
  height: auto;
  width: 100%;
}