The aspect-ratio CSS property sets a preferred aspect ratio for the box, which will be used in the calculation of auto sizes and some other layout functions.
Ref.: https://developer.mozilla.org/en-US/docs/Web/CSS/aspect-ratio
auto : CSS.Internal.Property
Replaced elements with an intrinsic aspect ratio use that aspect ratio, otherwise the box has no preferred aspect ratio. Size calculations involving intrinsic aspect ratio always work with the content box dimensions.
ratio : Basics.Float -> CSS.Internal.Property
The box's preferred aspect ratio is the specified ratio of width / height. If height and the preceding slash character are omitted, height defaults to 1. Size calculations involving preferred aspect ratio work with the dimensions of the box specified by box-sizing.
inherit : CSS.Internal.Property
Specifies that all the element's properties should be changed to their inherited values.
initial : CSS.Internal.Property
Specifies that all the element's properties should be changed to their initial values.
revert : CSS.Internal.Property
Specifies behavior that depends on the stylesheet origin to which the declaration belongs:
revertLayer : CSS.Internal.Property
Specifies that all the element's properties should roll back the cascade to a previous cascade layer, if one exists. If no other cascade layer exists, the element's properties will roll back to the matching rule, if one exists, in the current layer or to a previous style origin.
unset : CSS.Internal.Property
Specifies that all the element's properties should be changed to their inherited values if they inherit by default, or to their initial values if not.