Bootstrap 4 link

Example

a {
  color: #007bff;
  text-decoration: none;
  background-color: transparent;
}

a:hover {
  color: #0056b3;
  text-decoration: underline;
}

a:not([href]):not([class]) {
  color: inherit;
  text-decoration: none;
}

a:not([href]):not([class]):hover {
  color: inherit;
  text-decoration: none;
}