<!DOCTYPE html>
<style>
.negative {
  z-index: -1;
}
.abs {
  position: absolute;
}
.green {
  width: 100px;
  height: 100px;
  background-color: green;
}

.red {
  width: 100px;
  height: 100px;
  background-color: red;
  will-change: transform;
}
</style>
<body>
<div class="negative abs">
  <div class="red"></div>
</div>
<div class="negative abs green"></div>
</body>