.b2-container {
  text-align: center;
  margin: 20px 0; }

.b2 {
  background-color: var(--button-bg-color, black);
  color: var(--button-text-color, white);
  padding: 10px 15px;
  border-radius: 5px;
  text-decoration: none;
  transition: background-color 0.3s, color 0.3s;
  display: inline-block; }

.b2:hover {
  background-color: var(--button-text-color, white);
  color: var(--button-bg-color, black); }