how to put an position element absolute in centre code example

Example 1: centre align in position absolute

position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);

Example 2: center div absolute

#content {
  position: absolute; 
  left: 0; 
  right: 0; 
  margin-left: auto; 
  margin-right: auto; 
  width: 100px; /* Need a specific value to work */
}