1button {
2  font-size: 18px;
3  color: #e1e1e1;
4  font-family: inherit;
5  font-weight: 800;
6  cursor: pointer;
7  position: relative;
8  border: none;
9  background: none;
10  text-transform: uppercase;
11  transition-timing-function: cubic-bezier(0.25, 0.8, 0.25, 1);
12  transition-duration: 400ms;
13  transition-property: color;
14}
15
16button:focus,
17button:hover {
18  color: #fff;
19}
20
21button:focus:after,
22button:hover:after {
23  width: 100%;
24  left: 0%;
25}
26
27button:after {
28  content: "";
29  pointer-events: none;
30  bottom: -2px;
31  left: 50%;
32  position: absolute;
33  width: 0%;
34  height: 2px;
35  background-color: #fff;
36  transition-timing-function: cubic-bezier(0.25, 0.8, 0.25, 1);
37  transition-duration: 400ms;
38  transition-property: width, left;
39}