Use the .align-self-*-stretch classes to stretch a flex item in a flex container on different screens.
.align-self-stretch:
.align-self-stretch
.align-self-sm-stretch:
.align-self-sm-stretch
.align-self-md-stretch:
.align-self-md-stretch
.align-self-lg-stretch:
.align-self-lg-stretch
.align-self-xl-stretch:
.align-self-xl-stretch