Explanation on working with flex?

Question

Flexbox

The question is probably childish, but still. I'm trying to master the layout through flex, but it doesn't work. You need to center the block in the center, but it is not centered. Please explain how to do it right.

* {
  
}
body {
  margin: 0;
  padding: 0;
}
.wrapper {
  display: flex;
  flex-direction: column;
  justify-content: center;
  width: 1232px;
  min-height: 3000px;
  border: 2px solid red;
}

Answer 1

align-items: center;
https://codepen.io/justd/full/yydezN/