// HTML (after form)
<div class="process">
    <div class="loader">
      <div class="sk-fading-circle">
      <div class="sk-circle1 sk-circle"></div>
      <div class="sk-circle2 sk-circle"></div>
      <div class="sk-circle3 sk-circle"></div>
      <div class="sk-circle4 sk-circle"></div>
      <div class="sk-circle5 sk-circle"></div>
      <div class="sk-circle6 sk-circle"></div>
      <div class="sk-circle7 sk-circle"></div>
      <div class="sk-circle8 sk-circle"></div>
      <div class="sk-circle9 sk-circle"></div>
      <div class="sk-circle10 sk-circle"></div>
      <div class="sk-circle11 sk-circle"></div>
      <div class="sk-circle12 sk-circle"></div>
    </div>
    </div>
    <h4><span>Your registration</span> is currently in process…</h4>
  </div>


  // js (before post req.)
     $('form').fadeOut("fast", function () {
      var process = document.getElementsByClassName('process')[0];
      process.style.display = 'block';
    });

 // css

 .process {
  display: none;
}

 .process h4 {
    text-align: center;
 }

.process .loader {
    margin-bottom: 10px;
    height: 80px;
    background-position: center center;
    background-repeat: no-repeat;
}
.process, .loader {
  margin: 15px;
}
.sk-fading-circle {
    margin: 0px auto;
    width: 80px;
    height: 80px;
    position: relative;
}

.sk-fading-circle .sk-circle {

    width: 100%;
    height: 100%;
    position: absolute;
    left: 0;
    top: 0;

  }

  .sk-fading-circle .sk-circle:before {

    content: '';
    display: block;
    margin: 0 auto;
    width: 5%;
    height: 5%;
    background-color: #ccc;
    border-radius: 100%;
    -webkit-animation: sk-circleFadeDelay 1.2s infinite ease-in-out both;
    animation: sk-circleFadeDelay 1.2s infinite ease-in-out both;

  }

  .sk-fading-circle .sk-circle2 {

    -webkit-transform: rotate(30deg);
      -ms-transform: rotate(30deg);
          transform: rotate(30deg);

  }

  .sk-fading-circle .sk-circle3 {

    -webkit-transform: rotate(60deg);
      -ms-transform: rotate(60deg);
          transform: rotate(60deg);

  }

  .sk-fading-circle .sk-circle4 {

    -webkit-transform: rotate(90deg);
      -ms-transform: rotate(90deg);
          transform: rotate(90deg);

  }

  .sk-fading-circle .sk-circle5 {

    -webkit-transform: rotate(120deg);
      -ms-transform: rotate(120deg);
          transform: rotate(120deg);

  }

  .sk-fading-circle .sk-circle6 {

    -webkit-transform: rotate(150deg);
      -ms-transform: rotate(150deg);
          transform: rotate(150deg);

  }

  .sk-fading-circle .sk-circle7 {

    -webkit-transform: rotate(180deg);
      -ms-transform: rotate(180deg);
          transform: rotate(180deg);

  }

  .sk-fading-circle .sk-circle8 {

    -webkit-transform: rotate(210deg);
      -ms-transform: rotate(210deg);
          transform: rotate(210deg);

  }

  .sk-fading-circle .sk-circle9 {

    -webkit-transform: rotate(240deg);
      -ms-transform: rotate(240deg);
          transform: rotate(240deg);

  }

  .sk-fading-circle .sk-circle10 {

    -webkit-transform: rotate(270deg);
      -ms-transform: rotate(270deg);
          transform: rotate(270deg);

  }

  .sk-fading-circle .sk-circle11 {

    -webkit-transform: rotate(300deg);
      -ms-transform: rotate(300deg);
          transform: rotate(300deg);

  }

  .sk-fading-circle .sk-circle12 {

    -webkit-transform: rotate(330deg);
      -ms-transform: rotate(330deg);
          transform: rotate(330deg);

  }

  .sk-fading-circle .sk-circle2:before {

    -webkit-animation-delay: -1.1s;
          animation-delay: -1.1s;

  }

  .sk-fading-circle .sk-circle3:before {

    -webkit-animation-delay: -1s;
          animation-delay: -1s;

  }

  .sk-fading-circle .sk-circle4:before {

    -webkit-animation-delay: -0.9s;
          animation-delay: -0.9s;

  }

  .sk-fading-circle .sk-circle5:before {

    -webkit-animation-delay: -0.8s;
          animation-delay: -0.8s;

  }

  .sk-fading-circle .sk-circle6:before {

    -webkit-animation-delay: -0.7s;
          animation-delay: -0.7s;

  }

  .sk-fading-circle .sk-circle7:before {

    -webkit-animation-delay: -0.6s;
          animation-delay: -0.6s;

  }

  .sk-fading-circle .sk-circle8:before {

    -webkit-animation-delay: -0.5s;
          animation-delay: -0.5s;

  }

  .sk-fading-circle .sk-circle9:before {

    -webkit-animation-delay: -0.4s;
          animation-delay: -0.4s;

  }

  .sk-fading-circle .sk-circle10:before {

    -webkit-animation-delay: -0.3s;
          animation-delay: -0.3s;

  }

  .sk-fading-circle .sk-circle11:before {

    -webkit-animation-delay: -0.2s;
          animation-delay: -0.2s;

  }

  .sk-fading-circle .sk-circle12:before {

    -webkit-animation-delay: -0.1s;
          animation-delay: -0.1s;

  }

  @-webkit-keyframes sk-circleFadeDelay {

    0%, 39%, 100% { opacity: 0; }
    40% { opacity: 1; }

  }

  @keyframes sk-circleFadeDelay {

    0%, 39%, 100% { opacity: 0; }
    40% { opacity: 1; }

  }