body {
    background-color: black;
    margin: 0;
}

.square {
    width: 30%;
    background: purple;
    padding-bottom: 30%;
    float: left;
    margin: 1.66%;
    border-radius: 15%;
    transition: background 0.5s;
    /* will make it work in other browsers */
    -webkit-transition: background 0.5s;
    -moz-transition: background 0.5s;
}

#container {
  margin-top: 20px;
  margin-left: auto;
  margin-right: auto;
  max-width: 600px;   

}

h1 {
  text-align: center;
  line-height: 1;
  font-weight: normal;
  color: white;  
  background-color: steelblue;
  margin: 0;
  text-transform: uppercase;
  padding: 20px 0;
}

#message {
display: inline-block;
width: 20%;
}

#colorDisplay {
font-size: 200%;
}

#stripe {
    background-color: white;
    height: 30px;
    text-align: center;
    color: black;
}

.selected {
    color: white;
    background: steelblue;
}

button {
border: none; 
background: none;
text-transform: uppercase;
height: 100%;
font-weight: 700;
color: steelblue;
letter-spacing: 1px; 
font-size: inherit;
transition: all 0.3s;
outline: none;
 /* will make it work in other browsers */
 -webkit-transition: all 0.3s;
 -moz-transition: all 0.3s;
}

button:hover {
    color: white;
    background: steelblue;
}