I was working on a project requiring this kind of vertical slider. Each slide needed to have the same height so it wouldn't look jarring as you scrolled, and I just knew I was going to use the trusty grid-area: 1 / 1 / -1 / -1; solution to make all the slides fit the same space in the slider. I suspect a column-oriented flexbox solution with flex: 1 0 0 is equally viable.
