body{
  display: flex;
  flex-direction: column;
  text-align: center;
  background-color: hsl(0, 0%, 85%);
}
h1{
  font-size: 4em;
  color: hsl(0, 0%, 20%);
  text-shadow: 3px 3px 3px black;
}
#container{
  background-color: hsl(0, 0%, 97%);
  display: flex;
  flex-direction: column;
  border: 4px solid black;
  padding: 20px 50px;
  border-radius: 50px;
  margin: auto;
}
#display{
  font-size: 2em;
  font-weight: bold;
  font-family: monospace;
  margin-bottom: 10px;
  text-shadow: 1px 1px 2px black;
}
#btns button{
  padding: 5px 5px;
  width: 100px;
  font-weight: bold;
  font-size: 1.4em;
  border: none;
  border-radius: 10px;
  color: white;
  transition:  background-color ease 0.513 ;
}
#sb{
  background-color: hsl(149, 93%, 47%);
}
#sb:hover{
  background-color: hsl(149, 93%, 37%);
}
#tp{
  background-color: hsl(6, 93%, 47%);
}
#tp:hover{
  background-color: hsl(6, 93%, 37%);
}
#rb{
  background-color: hsl(215, 93%, 47%);
}
#rb:hover{
  background-color: hsl(215, 93%, 37%);
}