HoHCI-BikeSteering/Library/PackageCache/com.unity.shadergraph@7.3.1/Editor/Resources/Styles/PropertyNodeView.uss

PropertyNodeView.hovered #selection-border{
    background-color:rgba(68,192,255,0.4);
    border-color:rgba(68,192,255,1);
    border-left-width: 2px;
    border-right-width: 2px;
    border-top-width: 2px;
    border-bottom-width: 2px;
}