move container to the middle of page code example

Example 1: center with css

.parent {
  position: relative;
}
.child {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

Example 2: how to assign something in center inside a div

P { text-align: center }
H2 { text-align: center }