body {
  padding: 0;
  margin: 0;
  height: 100vh;
  width: 100%;
  background: #9E9E9E;
  display: flex;
  overflow: hidden;
}

.pixel-wrapper {
  width: 100%;
  height: 100%;
  margin: auto;
}

.pixel {
  background-color: white;
  width: 20px;
  height: 20px;
  display: block;
  float: left;
  transition: all 1000ms ease;
}