How can I remove vertical padding from ionic icon?

Here is my HTML :

<i class="icon ion-email notify-icon"></i>

and CSS:

.notify-icon {
  color: white;
  font-size: 35px;
  background-color: gray;
  padding: 0;
}

I set padding to 0 and it removes horizontal padding, but I still see 4-5px of gray padding on top and bottom. How can I solve it?