button {
  color: #fff;
  padding: 0.7em 1.7em;
  font-size: 18px;
  border-radius: 0.5em;
  background: #01080e;
  border: 1px solid #030e17;
  transition: all 0.3s;
  box-shadow:
    inset 4px 4px 4px #050505,
    inset -4px -4px 4px #ffffff16;
}

button:active {
  color: #999;
  box-shadow:
    inset 1px 1px 1px #000,
    inset -1px -1px 1px #ffffff16;
}