body, html
{
margin:3px;
padding:0px;
font-family: Arial, Helvetica, sans-serif;
text-align: center;
align: center;
}

h1
{
color: blue; 
text-align:center;
}

@media (min-width: 600px) {
body {
   background-color: lightblue;
}
}
@media (max-width: 599px) {
body {
    background-color: white;
}
}
#container {
  display: flex;
  flex-wrap: wrap;
  align: center;
  justify-content: space-around;
}

#container > div {
  background-color: lightgray;
  font-size: 20px;
  margin: 20px;
  padding: 20px;
  width: 100px;
  text-align: center;
}