The AlignContent property in the BaseStyles class represents the align-content CSS property. This property is used to define the alignment of the flexible container's items when the items do not use all available space on the cross-axis (the axis perpendicular to the main axis). It is applicable to flex containers and grid containers.

To use the AlignContent property, you can set it to one of the values defined in the Sandbox.UI.Align enumeration. These values include:

• Start - Aligns the content to the start of the container.
• Center - Aligns the content to the center of the container.
• End - Aligns the content to the end of the container.
• Stretch - Stretches the content to fill the container.
• SpaceBetween - Distributes the content evenly with the first item at the start and the last item at the end.
• SpaceAround - Distributes the content evenly with equal space around each item.
• SpaceEvenly - Distributes the content evenly with equal space between each item.

Example usage:

var styles = new BaseStyles();
styles.AlignContent = Align.Center;