move border color mixin to local space
move border color mixin to local space

auxcoder/hint.css,sarawuthza/hint.css,JKGisMe/hint.css,gdseller/hint.css,gdseller/hint.css,JKGisMe/hint.css,cnbin/hint.css,peteriou18/hint.css,Eurecam-Tristan/hint.css,webmechanicx/hint.css,sarawuthza/hint.css,GerHobbelt/hint.css,auxcoder/hint.css,chinchang/hint.css,webfby/hint.css,peteriou18/hint.css,cnbin/hint.css,chinchang/hint.css,Eurecam-Tristan/hint.css,webfby/hint.css,webmechanicx/hint.css