<div class="row middle-on-small center-on-small">
  <div class="column small-12 medium-6 large-4">
    <a href="#!" class="c-button c-button--gooey">
      Need mana
      <div class="c-button__blobs">
        <div></div>
        <div></div>
        <div></div>
      </div>
    </a>
    
    <p class="pen-info">Hover over the button</p>
  </div>
</div>

<svg xmlns="http://www.w3.org/2000/svg" version="1.1" style="display: block; height: 0; width: 0;">
    <defs>
        <filter id="goo">
            <feGaussianBlur in="SourceGraphic" stdDeviation="10" result="blur"></feGaussianBlur>
            <feColorMatrix in="blur" mode="matrix" values="1 0 0 0 0  0 1 0 0 0  0 0 1 0 0  0 0 0 18 -7" result="goo"></feColorMatrix>
            <feBlend in="SourceGraphic" in2="goo"></feBlend>
        </filter>
    </defs>
</svg>
$color-bluish: #06c8d9;

:root {
  font-size: 16px;
  font-family: 'Ubuntu', sans-serif;
}

html,
body,
.row {
  height: 100%;
  text-align: center;
}

.pen-info {
  color: #d4d3d4;
  font-size: 80%;
  text-transform: uppercase;
}

.c-button {
  color: #000;
  font-weight: 700;
  font-size: 1em;
  text-decoration: none;
  padding: .7em 1.8em;
  cursor: pointer;
  display: inline-block;
  vertical-align: middle;
}

.c-button--gooey {
  color: $color-bluish;
  font-size: 1.3em;
  text-transform: uppercase;
  letter-spacing: 2px;
  border: 4px solid $color-bluish;
  border-radius: 0;  
  padding: 1.2em 3.4em;
  position: relative;
  transition: all 700ms ease;
  .c-button__blobs {
    height: 100%;
    filter: url(#goo);
    overflow: hidden;
    position: absolute;
    top: 0;
    left: 0;
    bottom: -3px;
    right: -1px;
    z-index: -1;
    div {
      background-color: $color-bluish;
      width: 34%;
      height: 100%;
      border-radius: 100%;
      position: absolute;
      transform: scale(1.4) translateY(125%) translateZ(0);
      transition: all 700ms ease;
      &:nth-child(1) {
        left: -5%;
      }
      &:nth-child(2) {
        left: 30%;
        transition-delay: 60ms;
      }
      &:nth-child(3) {
        left: 66%;
        transition-delay: 25ms;
      }
    }
  }
  &:hover {
    color: #fff;
    .c-button__blobs {
      div {
        transform: scale(1.4) translateY(0) translateZ(0);
      }
    }
  }
}
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