my-chat-room/apps/chat-room/src/app/app.component.scss

.messages-container{
  display: flex;
  flex-flow: column-reverse nowrap;
  margin: 0px;
  border: 1px solid black;
  min-height: 80vh;
  max-height: 80vh;
  overflow-y: scroll;
}

.message {
  padding: 0.3rem;
  &:nth-child(odd){
    background: #EEEEEE;
  }
  &:nth-child(even) {
    background: #FFFFFF;
  }
}

input {
  width: 100%;
  margin: 0px;
  margin-top: 1rem;
}

.input-section {
  display: grid;
  grid-template-columns: 1fr 200px 30px;
}