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HTML 

              
                <section class="background">
  <div class="overlay">
    <svg class="vector" viewBox="0 0 388 170" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:sketch="http://www.bohemiancoding.com/sketch/ns">
    <defs>
      <filter id="goo">
      <feGaussianBlur in="SourceGraphic" stdDeviation="4" result="blur" />
      <feColorMatrix in="blur" mode="matrix" values="1 0 0 0 0  0 1 0 0 0  0 0 1 0 0  0 0 0 21 -9" result="cm" />
    </filter>
    </defs>
    <g filter="url(#goo)" id="Page-1" stroke="none" stroke-width="1" fill="none" fill-rule="evenodd" sketch:type="MSPage">
        <g id="halloween" sketch:type="MSLayerGroup" fill="#CD1E20">
            <text class="text" id="Halloween" sketch:type="MSTextLayer" transform="translate(220.433641, 82.816048) rotate(-2.000000) translate(-220.433641, -82.816048) " font-family="Creepster" font-size="72" font-weight="normal" letter-spacing="2.70000005">
                <tspan x="51.9336407" y="108.816048">Halloween</tspan>
            </text>
            <g class="group-1" id="Group-1" transform="translate(25.000000, 0.000000)" sketch:type="MSShapeGroup">
                <ellipse id="Oval-2" cx="329.5" cy="8" rx="7.5" ry="8"></ellipse>
                <circle id="Oval-2-Copy-2" cx="198" cy="36" r="6"></circle>
                <ellipse id="Oval-2-Copy-4" cx="155" cy="156.5" rx="9" ry="10.5"></ellipse>
                <circle id="Oval-2-Copy-12" cx="6" cy="112" r="6"></circle>
            </g>
            <g class="group-2" id="Group-2" transform="translate(0.000000, 16.000000)" sketch:type="MSShapeGroup">
                <ellipse id="Oval-2-Copy-7" cx="284.5" cy="8" rx="7.5" ry="8"></ellipse>
                <ellipse id="Oval-2-Copy-5" cx="373.5" cy="38" rx="7.5" ry="8"></ellipse>
                <circle id="Oval-1" cx="69.5" cy="130.5" r="6.5"></circle>
                <ellipse id="Oval-2-Copy-10" cx="5" cy="34.5" rx="5" ry="4.5"></ellipse>
            </g>
            <g class="group-3" id="group-3" transform="translate(232.000000, 130.000000)" sketch:type="MSShapeGroup">
                <ellipse id="Oval-2-Copy-3" cx="61" cy="10" rx="9" ry="10"></ellipse>
                <ellipse id="Oval-2-Copy-8" cx="6" cy="27" rx="6" ry="8"></ellipse>
                <ellipse id="Oval-2-Copy-6" cx="107.5" cy="28" rx="7.5" ry="12"></ellipse>
            </g>
            <g class="group-4" id="group-4" transform="translate(111.000000, 22.000000)" sketch:type="MSShapeGroup">
                <ellipse id="Oval-2-Copy-9" cx="11" cy="3" rx="4" ry="3"></ellipse>
                <ellipse id="Oval-2-Copy" cx="269.5" cy="100" rx="7.5" ry="8"></ellipse>
                <ellipse id="Oval-2-Copy-11" cx="10.5" cy="124" rx="10.5" ry="13"></ellipse>
            </g>
        </g>
    </g>
</svg>
  </div>
</section>
!

CSS 

              
                @import url(https://fonts.googleapis.com/css?family=Creepster);
@import "bourbon";

/* Only for demo */
html{
  height: 100%;
}
body{
  height: 100%;
  background-color: #111;
}
.background{
  display: inline-block;
  height: 100%;
  width: 100%;
  background-image: url(https://unsplash.it/g/1000/900?image=878);
  backround-repeat: no-repeat;
  background-size: cover;
  background-position: center center;
}
.overlay{
  display: inline-block;
  width: 100%;
  height: 100%;
  background-color: rgba(0,0,0,0.6);
}
.text{
  font-family: 'Creepster', cursive;
}

/* Where the magic happens */
.vector{
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  margin: auto;
  width: 100%;
  mix-blend-mode: screen;
}
.group-1{
  fill: #731113;
  @include animation(groupOne 34s);
}
.group-2{
  fill: #8e1517;
  @include animation(groupTwo 39s );
}
.group-3{
  fill: #350809;
  @include animation(groupThree 140s);
}
.group-4{
  fill: #d52023;
  @include animation(groupFour 43s);
}
.group-1, .group-2, .group-3, .group-4{
  @include animation-iteration-count(infinite);
  @include transform(translateZ(0));
}
/* Animations */
@include keyframes(groupOne) {
  0% {
    @include transform(translateY(0) rotate(-0deg) scale(0.8));
  }
  60% {
    @include transform(translateY(80px) rotate(-93deg) scale(1));
  }
  100% {
    @include transform(translateY(0) rotate(-0deg) scale(0.8));
  }
}

@include keyframes(groupTwo) {
  0% {
    @include transform(translateX(0)  translateY(0) rotate(-0deg) scale(0.6));
  }
  60% {
    @include transform(translateX(6px) translateY(-10px) rotate(4deg) scale(1));
  }
  100% {
    @include transform(translateX(0) translateY(0) rotate(-0deg) scale(0.6));
  }
}

@include keyframes(groupThree) {
  0% {
    @include transform(translateX(0)  translateY(0) rotate(-0deg));
  }
  60% {
    @include transform(translateX(400%) translateY(60px) rotate(14deg));
  }
  100% {
    @include transform(translateX(0) translateY(0) rotate(-0deg));
  }
}

@include keyframes(groupFour) {
  0% {
    @include transform(translateX(0)  translateY(0) rotate(-0deg));
  }
  60% {
    @include transform(translateX(-100%) translateY(-60px) rotate(-16deg));
  }
  100% {
    @include transform(translateX(0) translateY(0) rotate(-0deg));
  }
}
!

JS
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