Use the .align-content-*-end classes to align gathered items at the end on different screens.
Resize the browser window to see the effect.
.align-content-end:
.align-content-end
.align-content-sm-end:
.align-content-sm-end
.align-content-md-end:
.align-content-md-end
.align-content-lg-end:
.align-content-lg-end
.align-content-xl-end:
.align-content-xl-end