Gtk.Alignment.prototype.set_padding

function set_padding(padding_top:Number, padding_bottom:Number, padding_left:Number, padding_right:Number):void {
    // Gjs wrapper for gtk_alignment_set_padding()
}

Sets the padding on the different sides of the widget. The padding adds blank space to the sides of the widget. For instance, this can be used to indent the child widget towards the right by adding padding on the left.

Since 2.4

padding_top: the padding at the top of the widget
padding_bottom: the padding at the bottom of the widget
padding_left: the padding at the left of the widget
padding_right: the padding at the right of the widget.