.button_black {
  color: #fff;
  background-color: #000;
}
.button_black:hover,
.button_black:focus {
  border-color: #000;
  background-color: #eee;
  color: #000;
}
.button_black:active {
  top: 1px;
  outline: none;
  box-shadow: 0px 2px 8px 2px #939090 inset;
}