* {
  font-family:  sans-serif;
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
body {
  width: 100%;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: #333;
}

.buttons{
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  max-width: 140px;
  gap: 20px;
}

.buttons label{
  position: relative;
  width: 60px;
  height: 60px;
  display: flex;
  justify-content: center;
  align-items: center;
  cursor: pointer;
}

.buttons label input{
  appearance: none;
}
.buttons label span{
  position: absolute;
  width: 100%;
  height: 100%;
  background: linear-gradient(#555353, #363535);
  border: 2px solid #222;
  border-radius: 6px;
  box-shadow: inset 0 5px 1px rgba(0,0,0,0.35),
  0 5px 5px rgba(0,0,0,0.5),
  0 15px 25px rgba(0,0,0,0.35);
}
.buttons label input:checked ~ span{
  box-shadow: inset 0 2px 2px rgba(0,0,0,0.35),
  inset 0 5px 5px rgba(0,0,0,0.5),
  inset 0 15px 25px rgba(0,0,0,0.35);
}

.buttons label span::before{
  content: '';
  position: absolute;
  inset: 5px 3px;
  border-top: 1px solid #ccc;
  filter: blur(2px);
}
.buttons label i{
  position: relative;
  z-index: 10;
  font-size: 1.5rem;
  color: #111;
}

.buttons label input:checked ~ i{
  color: #fff;
  text-shadow: 0 0 5px #219cf3, 0 0 8px #219cf3;
}