html, body {
  height: 100%;
}

body {
  display: flex;
  overflow: hidden;
}

ul, li {
  list-style: none;
  margin: 0;
  padding: 0;
}

.white,
.black {
  flex: 1;
}

.white {
  background-color: #fff;
}

.black {
  background-color: #000;
}

canvas {
  position: absolute;
  top: 0;
  left: 0;
  padding: 0;
  margin: 0;
  z-index: 3;
  pointer-events: none;
  mix-blend-mode: difference;
}

header {
  display: flex;
  position: fixed;
  top: 3rem;
  right: 4rem;
  z-index: 2;
}
header li {
  color: #fff;
  padding: 0.5rem;
  margin-left: 3rem;
}