This is hard to anwser without knowing the contents of the columns. Also, I don't understand how align-items-stretch is giving your columns ... ... <看更多>

Flexbox utilities for bootstrap 3. GitHub Gist: instantly share code, notes, ... align-items: flex-start;. } &.align-items-end { ... align-items: stretch;. ... <看更多>

align -content-around and .align-content-stretch. Note: These classes have no effect on single rows of ... ... <看更多>