body {
  background: #008080;
}

.box {
  margin-left: 50%;
  margin-bottom: 50px;
  border: solid #5c5c5c;
  border-width: 1px;
  padding: 20px;
  width: 512px;
  background: #bebebe;
  color: #23201d;
  transform: translate(-50%, 0);
}

.block {
  display: block;
  text-align: center;
  margin-left: auto;
  margin-right: auto;
}