how to center vertically in css flexbox code example

Example 1: css flex vertical align

/* Answer to: "css flex vertical align" */

.box {
  display: flex;
  align-items: center; /* Vertical */
  justify-content: center; /* Horizontal */
}

.box div {
  width: 100px;
  height: 100px;
}

/*
  For more information go to:
  https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Flexible_Box_Layout/Aligning_Items_in_a_Flex_Container
*/

Example 2: flexbox align center vertically

.Aligner {
  display: flex;
  align-items: center;
  justify-content: center;
}

.Aligner-item {
  max-width: 50%;
}

.Aligner-item--top {
  align-self: flex-start;
}

.Aligner-item--bottom {
  align-self: flex-end;
}