.flex {
  display: flex;
  flex-wrap: wrap;
}

#original-text {
  font-size: 2.2em;
  min-height: 50px
}

#paralel-text {
  font-size: 1.8em;
  min-height: 40px
}

#block-area {
  overflow: scroll;
  border: 1px solid black;
  padding: 5px;
}