static/scss/bootstrap-4.0.0-alpha.6/scss/utilities/_align.scss

   1 .align-baseline    { vertical-align: baseline !important; } // Browser default
   2 .align-top         { vertical-align: top !important; }
   3 .align-middle      { vertical-align: middle !important; }
   4 .align-bottom      { vertical-align: bottom !important; }
   5 .align-text-bottom { vertical-align: text-bottom !important; }
   6 .align-text-top    { vertical-align: text-top !important; }