The correct value is none
:
.myelements {
@include box-shadow(2px 2px 3px #000);
}
@media (max-width: 768px) {
.myelements {
@include box-shadow(none);
}
}
However, you should avoid repeatedly setting/unsetting properties whenever possible to get a smaller CSS file:
.myelements {
// nothing
}
@media (min-width: 768px) {
.myelements {
@include box-shadow(2px 2px 3px #000);
}
}