fab button

con css

HTML

<div class="fab fab-br">
  <div class="icono">
    <svg style="width:24px;height:24px" viewBox="0 0 24 24">
<path fill="#fff" d="M13,9H18.5L13,3.5V9M6,2H14L20,8V20A2,2 0 0,1 18,22H6C4.89,22 4,21.1 4,20V4C4,2.89 4.89,2 6,2M6,20H15L18,20V12L14,16L12,14L6,20M8,9A2,2 0 0,0 6,11A2,2 0 0,0 8,13A2,2 0 0,0 10,11A2,2 0 0,0 8,9Z" /></svg>
  </div>
</div>

CSS

.fab {
  height: 56px;
  width: 56px;
  background-color: #E40A5D;
  display: inline-block;
  border: none;
  border-radius: 50%;
  box-shadow: 0 0 4px rgba(0, 0, 0, .14), 0 4px 8px rgba(0, 0, 0, .28);
  cursor: pointer;
  outline: 0;
  padding: 0;
  position: relative;
  -webkit-user-drag: none;
  font-weight: 700;
  color: #f1f1f1;
}
.icono {
  position: absolute;
  top: 28%;
  left: 28%;
}
.fab-br { position:fixed;margin: 25px; bottom: 0;right: 0;}