<div class="content-container">
  <div class="img-container"></div>
  <div class="blur"></div>
</div>

body,
html {
  margin: 0;
}

.img-container {
  background-image: url(http://www.placekitten.com/1500/1500);
  position: absolute;
  height: 100%;
  width: 100%;
  -webkit-filter: blur(70px);
  -o-filter: blur(70px);
  filter: blur(70px);
  filter: progid: DXImageTransform.Microsoft.Blur(PixelRadius='70');
  background-size: cover;
}

.content-container {
  width: 100%;
  height: 1000px;
  position: relative;
  overflow: hidden;
  -webkit-transform: translateZ(0);
  -ms-transform: translateZ(0);
  -o-transform: translateZ(0);
  transform: translateZ(0);
}

.blur {
  /* All the background image supports */
  background-image: -webkit-linear-gradient(bottom left, rgba(43, 40, 50, 0.8) 0%, rgba(83, 86, 99, 0.8) 45%, rgba(69, 77, 91, 0.6) 60%);
  background-image: -moz-linear-gradient(bottom left, rgba(43, 40, 50, 0.8) 0%, rgba(83, 86, 99, 0.8) 45%, rgba(69, 77, 91, 0.6) 60%);
  background-image: -o-linear-gradient(bottom left, rgba(43, 40, 50, 0.8) 0%, rgba(83, 86, 99, 0.8) 45%, rgba(69, 77, 91, 0.6) 60%);
  background-image: linear-gradient(to top right, rgba(43, 40, 50, 0.8) 0%, rgba(83, 86, 99, 0.8) 45%, rgba(69, 77, 91, 0.6) 60%);
  position: absolute;
  width: 100%;
  height: 100%;
  -webkit-filter: blur(50px);
  -o-filter: blur(50px);
  filter: blur(50px);
  filter: progid: DXImageTransform.Microsoft.Blur(PixelRadius='70');
  top: -70px;
  right: -70px;
  left: -70px;
  padding: 70px;
}

.blur:after {
  content: '';
  position: absolute;
  height: 100%;
  width: 100%;
  z-index: 1001;
  background-image: -webkit-linear-gradient(339deg, rgba(43, 40, 50, 0.8) 0%, rgba(43, 40, 50, 0.4) 46%, rgba(0, 0, 0, 0.05) 50%);
  background-image: -moz-linear-gradient(339deg, rgba(43, 40, 50, 0.8) 0%, rgba(43, 40, 50, 0.4) 46%, rgba(0, 0, 0, 0.05) 50%);
  background-image: -o-linear-gradient(339deg, rgba(43, 40, 50, 0.8) 0%, rgba(43, 40, 50, 0.4) 46%, rgba(0, 0, 0, 0.05) 50%);
  background-image: linear-gradient(339deg, rgba(43, 40, 50, 0.8) 0%, rgba(43, 40, 50, 0.4) 46%, rgba(0, 0, 0, 0.05) 50%);
  -webkit-filter: blur(70px);
  -o-filter: blur(70px);
  filter: progid: DXImageTransform.Microsoft.Blur(PixelRadius='70');
  filter: blur(70px);
}