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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class='hero' id='one'>
  <div class='filter'></div>
  <h1 class='hero-text'>HELLO, WORLD 1</h1>
</div>

<div class='hero' id='two'>
  <div class='filter'>
    <h1 class='hero-text'>HELLO, WORLD 2</h1>
  </div>
</div>

<div class='hero' id='three'>
  <h1 class='hero-text'>HELLO, WORLD 3</h1>
</div>
!

CSS 

              
                /*
Method 1: Intermediate element. Need to position and size it the same as the background. Notice the use of z-index to ensure that the siblings appear on top. Would have to apply this to all siblings.
*/
#one {
  .filter {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    backdrop-filter: blur(10px) brightness(90%);
    z-index: 2;
  }
  .hero-text {
    z-index: 3;
  }
}

/*
Method 2: Nesting elements. Doesn't require use of z-index, so adding more child elements isn't as complex. I think this is the best solution. 
*/
#two {
  /* down below, the .hero elements are all display flex, had to reset that here. In other cases, this won't be necessary*/
  display: block;
  .filter {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100vw;
    height: 100vh;
    backdrop-filter: blur(10px) brightness(90%);
  } 
}

/*
Method 3: Child element the same size as parent. Least ideal, IMO, because it doesn't allow for other child elements/flex displays. Also requires some math to position the text. Also, doesn't allow for screen-height changes. Kinda the worst here, actually.
*/
#three {
  .hero-text {
    width: 100vw;
    backdrop-filter: blur(10px) brightness(90%);
    padding-top: calc(50% - .5em);
    padding-bottom: calc(50% - .5em);
  }
}

.hero {
  background-image: url(https://images.unsplash.com/photo-1526943604017-955071a1fb3e?ixlib=rb-1.2.1&ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&auto=format&fit=crop&w=1500&q=80);
  background-position: center center;
  background-repeat: no-repeat;
  width: 100vw;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  .hero-text {
    color: white;
    padding: .35em;
    font-family: 'Old Standard TT', serif;
    font-size: 4em;
  }
}
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JS
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