share.css

#shareButton {
  position: fixed;
  right: 40px;
  bottom: 40px;
  width: 2.5em;
  height: 2.5em;
  font-size: 24px;
  border-radius: 50%;
  border: 0;
  outline: 0;
  background: linear-gradient(135deg, hsl(0, 100%, 30%), hsl(330, 100%, 40%));
  color: #fff;
  box-shadow: 2px 3px 8px 2px hsla(330, 100%, 40%, 0.4);
  cursor: pointer;
  transition: 0.3s;
  -webkit-tap-highlight-color: transparent;
}

#shareButton:hover {
  box-shadow: 4px 6px 16px 4px hsla(330, 100%, 40%, 0.4);
}

#shareButton i {
  position: absolute;
  transform: translate(-50%, -50%);
  left: 1.2em;
  top: 1.3em;
  transition: 0.6s;
}

#shareButton > .container {
  position: absolute;
  width: 200px;
  background: hsl(0, 40%, 95%);
  bottom: 100%;
  right: 0;
  padding: 8px;
  box-shadow: 0 0 1px 0 hsla(330, 100%, 40%, 0.4),
    2px 3px 8px 2px hsla(330, 100%, 40%, 0.4);
  margin-bottom: 16px;
  border-radius: 4px;
  opacity: 0;
  visibility: hidden;
  transition: 0.3s;
  transform: translateY(10%);
}

#shareButton > .container:hover {
  box-shadow: 0 0 1px 0 hsla(330, 100%, 40%, 0.4),
    4px 6px 16px 4px hsla(330, 100%, 40%, 0.4);
}

#shareButton.showAddThisButtons > .container {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.addthis_inline_share_toolbox,
.addthis_sharing_toolbox {
  text-align: right;
}

#shareButton:after {
  content: "";
  position: absolute;
  top: 2px;
  bottom: 2px;
  left: 2px;
  right: 2px;
  border: 0 solid #fff;
  border-radius: 50%;
  border-width: 2px 0 0 2px;
  border-left-color: transparent;
  animation: loading-share-buttons 1s cubic-bezier(0.4, 0.6, 0.4, 0.6) infinite;
  animation-play-state: paused;
  opacity: 0;
  transition: 0.3s;
}

#shareButton.loading:after {
  animation-play-state: running;
  opacity: 1;
}

#shareButton i.fa-times {
  opacity: 0;
  left: 1.22em;
  transform: translate(-50%, -50%) rotate(180deg);
}

#shareButton.showAddThisButtons i.fa-share-alt {
  opacity: 0;
  transform: translate(-50%, -50%) rotate(180deg);
}

#shareButton.showAddThisButtons i.fa-times {
  opacity: 1;
  transform: translate(-50%, -50%) rotate(360deg);
}

@keyframes loading-share-buttons {
  to {
    transform: rotate(-360deg);
  }
}