.frame {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 400px;
    height: 400px;
    margin-top: -200px;
    margin-left: -200px;
    border-radius: 2px;
    box-shadow: 4px 8px 16px 0 rgba(0, 0, 0, 0.1);
    overflow: hidden;
    background: #fff;
    color: #333;
    font-family: "Open Sans", Helvetica, sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.center {
    position: absolute;
    top: 0;
    left: 0;
    width: 400px;
    height: 400px;
    box-sizing: border-box;
}

.bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 400px;
    height: 400px;
    background-color: #3498db;
    border-left: 400px solid #9b59b6;
	border-right: 400px solid #1abc9c;
	z-index: 1;
	transform: translateX(0);
	transition: transform 1s ease;
}

input[type="radio"] {
  display: none;
}

label {
	position: absolute;
	width: 50px;
	height: 50px;
	z-index: 3;
	border: 2px solid #fff;
	border-radius: 50%;
	top: 175px;
	cursor: pointer;
}

#c1 {
	left: 115px;
}

#c2 {
	left: 175px;
}

#c3 {
	left: 235px;
}

.ball {
	position: absolute;
	top: 182px;
	left: 122px;
	width: 40px;
	height: 40px;
	background-color: #fff;
	border-radius: 50%;
	z-index: 2;
	box-sizing: border-box;
	transform: translateX(0);
	transition: all ease 1s;
}

#check-2:checked ~ .ball {
	transform: translateX(60px);
}

#check-2:checked ~ .bg {
	transform: translateX(-400px);
}

#check-3:checked ~ .bg {
	transform: translateX(-800px);
}

#check-3:checked ~ .ball {
	transform: translateX(120px);
}