Template:Cell hover show more/styles.css

/*
 * fixed table layout
 */
table {
  table-layout: fixed;
}
/*
 * width and overflow
 * inline-block elements expand as much as content
 * relative position makes z-index work
 * explicit width and nowrap makes overflow work
 */
.showmore {
  display: inline-block;
  position: relative;
  width: 100%;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/*
 * higher z-index brings element to front
 * auto width cancels the overflow
 */
.showmore:hover {
  z-index: 1;
  white-space: normal;
  width: auto;
}