By default items start from the left if flex-direction is row, and from the top if flex-direction is column.

You can change this behavior using justify-content to change the horizontal alignment, and align-items to change the vertical alignment.

Change the horizontal alignment

justify-content has 5 possible values:

• flex-start: align to the left side of the container.
• flex-end: align to the right side of the container.
• center: align at the center of the container.
• space-between: display with equal spacing between them.
• space-around: display with equal spacing around them

Change the vertical alignment

align-items has 5 possible values:

• flex-start: align to the top of the container.
• flex-end: align to the bottom of the container.
• center: align at the vertical center of the container.
• baseline: display at the baseline of the container.
• stretch: items are stretched to fit the container.

A note on baseline

baseline looks similar to flex-start in this example, due to my boxes being too simple. Check out this Codepen to have a more useful example, which I forked from a Pen originally created by Martin Michálek. As you can see there, items dimensions are aligned.

Lessons in this unit:

0:	Introduction
1:	Align rows or columns
2:	▶︎ Vertical and horizontal alignment
3:	Wrap
4:	Moving items before / after another one using order
5:	Vertical alignment using align-self
6:	Grow or shrink an item if necessary
7:	DEMO Create a layout using Flexbox