body{ 
  background-color: red; 
}

h1{
  color:red
}

#result{ 
  background-color: red;
  
}


#container { 
  position:fixed;
  top:50%;
  left:50%;
  transform: translate(-50%, -50%);
  background-color: yellow;
  border-radius: 1em;
  padding: 20px;
}


#result {  text-align:center
}