#red-box
{
  background: red;
}

#orange-box
{
  background: orange;
}

#yellow-box
{
  background: yellow;
}

#green-box
{
  background: green;
}

#blue-box
{
  background: blue;
}

#violet-box
{
  background: violet;
}

div
{
  height: 100px;
  width: 100px;
  border-radius: 50%;
  margin: auto;
  margin-bottom: 10px;
}