#container{
  
  background-color: #040415;
  color: forestgreen;
  border: 0.5em solid slateblue;
  display: flex;
  flex-flow: column wrap;

}

#container h1 {
  text-align: center;
  color: forestgreen;
}

#container button{
  color: green;
  width: 15%;
}

#firstNum{
  width: 25%;
}

#secondNum{
  width: 25%;
}

#jsResult{
  font-size: 25px;
  color: forestgreen;
}