Кнопка с уведомлением

Пример

<a href="#" class="notification">
  <span>Входящие</span>
  <span class="badge">3</span>
</a>

Пример

.notification {
  background-color: #555;
  color: white;
  text-decoration: none;
  padding: 15px 26px;
  position: relative;
  display: inline-block;
  border-radius: 2px;
}

.notification:hover {
  background: red;
}

.notification .badge {
  position: absolute;
  top: -10px;
  right: -10px;
  padding: 5px 10px;
  border-radius: 50%;
  background: red;
  color: white;
}