.relative {
  position: relative;
}

.absolute {
  position: absolute;
}

.fixed {
  position: fixed;
}

.top-0 {
  top: 0;
}

.right-0 {
  right: 0;
}

.bottom-0 {
  bottom: 0;
}

.left-0 {
  left: 0;
}

.z-1 {
  z-index: 1;
}

.z-2 {
  z-index: 2;
}

.z-3 {
  z-index: 3;
}

.z-4 {
  z-index: 4;
}