I currently developing a game and i currently have four buttons,
I am looking to turn those 4 colored buttons in curvy line shapes like the example below

I have linked my css and made a fiddle so you guys can see what i have.
JSFIDDLE - http://jsfiddle.net/eh7h7pn1/
Github download and unzip to see the game fully https://github.com/Jamiex304/Simon_Says_Game_Demo
My CSS
body {
background-color: #333;
color: #fff;
}
ul {
list-style: none;
margin: 0 0 20px 0;
padding: 0;
text-align: center;
}
li {
display: inline-block;
padding: 3px;
}
.wrapper {
margin-top:10px;
margin-bottom:20px;
width: 650px;
height: 50px;
background-color:black;
position: relative;
margin: 0 auto;
border-style: solid;
border-width: 5px;
}
.wrapper2 {
position: relative;
width: 650px;
height: 700px;
margin: 0 auto;
border-style: solid;
border-width: 5px;
}
.wrapper3{
position: relative;
margin-top:20px;
width: 650px;
height: 170px;
margin: 0 auto;
background-color:black;
border-style: solid;
border-width: 5px;
}
.Timer{
width:300px;
height:200px;
margin-top:235px;
margin-left:177px;
border:5px solid white;
border-radius: 50%;
background-color:black;
text-align:center;
}
.pad {
z-index: 1;
margin: 10px;
-ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=60)";
filter: alpha(opacity=60);
opacity: 0.6;
}
.shape1 {
position: absolute;
left: 50%;
margin-left: -50px;
width: 125px;
height: 125px;
background-color: green;
border-radius: 50%;
}
.shape2 {
position: absolute;
left: 50%;
bottom: 2.5px;
margin-left: -50px;
width: 125px;
height: 125px;
background-color: red;
border-radius: 50%;
}
.shape3 {
position: absolute;
left: 78%;
right: 50%;
bottom: 50%;
margin-bottom: -50px;
margin-right: -50px;
width: 125px;
height: 125px;
background-color: purple;
border-radius: 50%;
}
.shape4 {
position: absolute;
left: 0;
bottom: 50%;
margin-bottom: -50px;
width: 125px;
height: 125px;
background-color: blue;
border-radius: 50%;
}
.level, .score {
width: 50%;
float: left;
text-align: center;
}
.sButton {
width: 30%;
margin: 0 auto;
color: black;
border: 3pt ridge Black;
font-weight: bold;
}
.start {
width: 100%;
height: 30px;
text-align: center;
}