I have a div that, when clicked, the button inside of it will create an outline around it, like so:
**Code: **
.slide-arrow {
  color: #fff;
  background-color: #9E9997;
  border: none;
  padding: 16px 10px 17px 10px;
  font-size: 25px;
  opacity: 0.5;
  outline: 0;
}
.slide-arrow-right {
  position: absolute;
  top: 50%;
  right: 0%;
  transform: translate(0%, -50%);
  -ms-transform: translate(0%, -50%);
  margin-right: -1px;
  border-bottom-left-radius: 4px;
  border-top-left-radius: 4px;
}
.slide-arrow-left {
  position: absolute;
  top: 50%;
  left: 0%;
  transform: translate(0%, -50%);
  -ms-transform: translate(-0%, -50%);
  border-bottom-right-radius: 4px;
  border-top-right-radius: 4px;
}
.slide-arrow:hover {
  opacity: 0.7;
}
.slide-arrow:active {
  background-color: #D47C7C;
}
.slide-arrow i {
  font-size: 32px;
  outline: 0 !important;
}
.slide-arrow i:focus {
  outline: 0 !important;
}
<button class="slide-arrow slide-arrow-right" onclick="plusDivs(1)"><i class="fa fa-angle-double-right"></i></button>
I want this removed. But when applying outline: 0 !important; to just about everything, nothing seems to work. This only seems to happen in firefox.
