Button by njesenberger

1.button {
2  -webkit-appearance: none;
3  appearance: none;
4  position: relative;
5  border-width: 0;
6  padding: 0 8px 12px;
7  min-width: 10em;
8  box-sizing: border-box;
9  background: transparent;
10  font: inherit;
11  cursor: pointer;
12}
13
14.button-top {
15  display: flex;
16  align-items: center;
17  justify-content: center;
18  position: relative;
19  z-index: 0;
20  padding: 8px 16px;
21  transform: translateY(0);
22  text-align: center;
23  color: #fff;
24  text-shadow: 0 -1px rgba(0, 0, 0, .25);
25  transition-property: transform;
26  transition-duration: .2s;
27  -webkit-user-select: none;
28  user-select: none;
29}
30
31.button:active .button-top {
32  transform: translateY(6px);
33}
34
35.button-top::after {
36  content: '';
37  position: absolute;
38  z-index: -1;
39  border-radius: 4px;
40  width: 100%;
41  height: 100%;
42  box-sizing: content-box;
43  background-image: radial-gradient(#cd3f64, #9d3656);
44  text-align: center;
45  color: #fff;
46  box-shadow: inset 0 0 0px 1px rgba(255, 255, 255, .2), 0 1px 2px 1px rgba(255, 255, 255, .2);
47  transition-property: border-radius, padding, width, transform;
48  transition-duration: .2s;
49}
50
51.button:active .button-top::after {
52  border-radius: 6px;
53  padding: 0 2px;
54}
55
56.button-bottom {
57  position: absolute;
58  z-index: -1;
59  bottom: 4px;
60  left: 4px;
61  border-radius: 8px / 16px 16px 8px 8px;
62  padding-top: 6px;
63  width: calc(100% - 8px);
64  height: calc(100% - 10px);
65  box-sizing: content-box;
66  background-color: #803;
67  background-image: radial-gradient(4px 8px at 4px calc(100% - 8px), rgba(255, 255, 255, .25), transparent), radial-gradient(4px 8px at calc(100% - 4px) calc(100% - 8px), rgba(255, 255, 255, .25), transparent), radial-gradient(16px at -4px 0, white, transparent), radial-gradient(16px at calc(100% + 4px) 0, white, transparent);
68  box-shadow: 0px 2px 3px 0px rgba(0, 0, 0, 0.5), inset 0 -1px 3px 3px rgba(0, 0, 0, .4);
69  transition-property: border-radius, padding-top;
70  transition-duration: .2s;
71}
72
73.button:active .button-bottom {
74  border-radius: 10px 10px 8px 8px / 8px;
75  padding-top: 0;
76}
77
78.button-base {
79  position: absolute;
80  z-index: -2;
81  top: 4px;
82  left: 0;
83  border-radius: 12px;
84  width: 100%;
85  height: calc(100% - 4px);
86  background-color: rgba(0, 0, 0, .15);
87  box-shadow: 0 1px 1px 0 rgba(255, 255, 255, .75), inset 0 2px 2px rgba(0, 0, 0, .25);
88}