src/scss/bootstrap-4.0.0-alpha.6/scss/_transitions.scss

   1 .fade {
   2   opacity: 0;
   3   @include transition($transition-fade);
   4
   5   &.show {
   6     opacity: 1;
   7   }
   8 }
   9
  10 .collapse {
  11   display: none;
  12   &.show {
  13     display: block;
  14   }
  15 }
  16
  17 tr {
  18   &.collapse.show {
  19     display: table-row;
  20   }
  21 }
  22
  23 tbody {
  24   &.collapse.show {
  25     display: table-row-group;
  26   }
  27 }
  28
  29 .collapsing {
  30   position: relative;
  31   height: 0;
  32   overflow: hidden;
  33   @include transition($transition-collapse);
  34 }