.qr-generator-container select,
.qr-generator-container input,
.qr-generator-container button {
  margin: 10px auto;
  display: block;
  padding: 10px;
  font-size: 16px;
  width: 100%;
  max-width: 400px;
}

.qr-generator-container button {
  background: rgba(27,151,111,0.72);
  color: white;
  border: none;
  border-radius: 5px;
}

.qr-generator-container button:hover {
  background: rgba(27,151,111,1);
}