.nes-btn.is-dark {
  border-image-source: url('data:image/svg+xml;utf8,<?xml version="1.0" encoding="UTF-8" ?><svg version="1.1" width="5" height="5" xmlns="http://www.w3.org/2000/svg"><path d="M2 1 h1 v1 h-1 z M1 2 h1 v1 h-1 z M3 2 h1 v1 h-1 z M2 3 h1 v1 h-1 z" fill="rgb(255,255,255)" /></svg>');
  outline-color: #e7e7e7;
  color: #fff;
  background-color: #212529;
}

.nes-btn {
  font-size: 8px;
}