Offets are included because both individual browser settings and font types and font sizes can appear different in different browsers. If the Heading or Text are on an angle, this can also affect the positioning on the card.
When the Design window content doesn’t line up with the Result window, use Offsets to align them.
Offsets are numbers and correspond with pixels. They can be both negative (-50) and positive (50).
Making them negative or positive changes the direction of the alignment.