how to create wave like border

1#wave {
2  position: relative;
3  height: 70px;
4  width: 600px;
5  background: #e0efe3;
6}
7#wave:before {
8  content: "";
9  display: block;
10  position: absolute;
11  border-radius: 100% 50%;
12  width: 340px;
13  height: 80px;
14  background-color: white;
15  right: -5px;
16  top: 40px;
17}
18#wave:after {
19  content: "";
20  display: block;
21  position: absolute;
22  border-radius: 100% 50%;
23  width: 300px;
24  height: 70px;
25  background-color: #e0efe3;
26  left: 0;
27  top: 27px;
28}