<div class="loader-wrapper">
  <div class="loader">
    <div class="ball"></div>
    <div class="ball"></div>
    <div class="ball"></div>
  </div>
  <div class="text">LOADING...</div>
</div>

html,
body {
  margin: 0;
  padding: 0;
  border: 0;
}

.loader-wrapper {
  position: fixed;
  width: 100%;
  height: 100%;
  z-index: 100;
  background-color: cornflowerblue;
}

.loader-wrapper .text {
  position: absolute;
  bottom: 0;
  left: 50%;
  -webkit-transform: translateX(-50%);
  -ms-transform: translateX(-50%);
  transform: translateX(-50%);
  margin: 0 0 100px;
  color: rgba(255, 255, 255, .7);
  text-transform: uppercase;
  font-size: 11px;
  font-family: sans-serif, helvetica;
  letter-spacing: .5px;
}

.loader {
  position: absolute;
  top: 50%;
  left: 50%;
  -webkit-transform: translate(-50%, -50%);
  -ms-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);
  width: 300px;
  height: 24px;
  border-left: 8px solid #fff;
  border-right: 8px solid #fff;
  overflow: hidden;
}

.loader .ball {
  height: 8px;
  width: 0;
  background: white;
  position: relative;
  margin: 0;
}

.loader .ball:nth-child(1) {
  -webkit-animation: ball 2s ease-in-out infinite;
  animation: ball 2s ease-in-out infinite;
}

.loader .ball:nth-child(2) {
  -webkit-animation: ball 2s ease-in-out .1s infinite;
  animation: ball 2s ease-in-out .1s infinite;
}

.loader .ball:nth-child(3) {
  -webkit-animation: ball 2s ease-in-out .2s infinite;
  animation: ball 2s ease-in-out .2s infinite;
}

@-webkit-keyframes ball {
  0% {
    left: 0;
    width: 0px;
  }
  25% {
    left: 0;
    width: 300px;
  }
  50% {
    left: 300px;
    width: 0px;
  }
  75% {
    left: 0;
    width: 300px;
  }
  100% {
    left: 0;
    width: 0px;
  }
}

@keyframes ball {
  0% {
    left: 0;
    width: 0px;
  }
  25% {
    left: 0;
    width: 300px;
  }
  50% {
    left: 300px;
    width: 0px;
  }
  75% {
    left: 0;
    width: 300px;
  }
  100% {
    left: 0;
    width: 0px;
  }
}