align-items:

The CSS property "align-items" is used to align the flex items along the cross axis of the flex container. It sets the default alignment for all the flex items, unless overridden by the "align-self" property.

The possible values for "align-items" are:

- flex-start: aligns the flex items at the start of the cross axis
- flex-end: aligns the flex items at the end of the cross axis
- center: aligns the flex items at the center of the cross axis
- baseline: aligns the flex items at the baseline of the cross axis
- stretch: stretches the flex items to fill the cross axis

Example usage:

.container {
display: flex;
align-items: center; /* aligns the items at the center of the cross axis */
}