There are two ways to vertically center contents with the introduction of flex box.

The first is:

```
.is-vertical-center {
  display: flex;
  align-items: center;
}

```

The other is:

```
.is-vertical-center {
  display: grid;
  place-items: center center;
}

```

Visually, both look the same. What are actual differences between the two?