The popup-position CSS property accepts one of followng formats:
popup-position: default; - default positioning (behavior specific).popup-position: inherit; - inherit the value from its paren.tpopup-position: <popup-reference-point> <anchor-reference-point>; - explicit position.Where:
<popup-reference-point> and <anchor-reference-point> are enumeration values:
top-lefttop-centertop-rightmiddle-leftmiddle-centermiddle-rightbottom-leftbottom-centerbottom-rightExample, this declaration:
select > popup {
popup-position: top-right bottom-right;
}
will position the popup element in the way that its top-right corner is placed at bottom-right corner of the anchor element (the select itself here).