This is different from the previous example in that it uses
Align instead of Center.

Align also tells the Container that it can be any size it
wants, but if there is empty space it won’t center the Container.
Instead, it aligns the container to the bottom-right of the
available space.

Example 5

The screen forces the Center to be exactly the
same size as the screen, so the Center fills the screen.

The Center tells the Container that it can be any size it wants,
but not bigger than the screen. The Container wants to be
of infinite size, but since it can’t be bigger than the screen,
it just fills the screen.

Example 6

The screen forces the Center to be exactly the
same size as the screen, so the Center fills the screen.