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CSS

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HTML 

              
                <div class="block-wrap">
  <div class="block-col">
    <div class="block block--transition r">
      <div class="block-content">
        <div class="block-content__header">
          <h2 class="block-content__header__text">Red</h2>
        </div>
        <p class="block-content__body">Red is the color at the end of the visible spectrum of light, next to orange and opposite violet. It has a dominant wavelength of approximately 625–740 nm.</p>
        <div class="block-content__button">
          Neato
        </div>
      </div>
    </div>
  </div>
  <div class="block-col">
    <div class="block block--transition  b">
      <div class="block-content">
        <div class="block-content__header">
          <h2 class="block-content__header__text">Blue</h2>
        </div>
        <p class="block-content__body">Blue is one of the three primary colours of pigments in painting and traditional colour theory, as well as in the RGB colour model. It lies between violet and green on the spectrum of visible light.</p>
        <div class="block-content__button">
          Very Cool
        </div>
      </div>
    </div>
  </div>
  <div class="block-col">
    <div class="block block--transition y">
      <div class="block-content">
        <div class="block-content__header">
          <h2 class="block-content__header__text">Yellow</h2>
        </div>
        <p class="block-content__body">Yellow is the color between orange and green on the spectrum of visible light. It is evoked by light with a dominant wavelength of roughly 570–590 nm. It is a primary color in subtractive color systems.</p>
        <div class="block-content__button">
          Yikes this one's low contrast
        </div>
      </div>
    </div>
  </div>
</div>
!

CSS 

              
                $xlt-gray: #efefef;
$red: #f44336;
$blue: #1e88e5;
$yellow: #fdd835;

$hoverTranslate: 12px;

$container-size: 360px;
$block-size: 64px;

$ease: cubic-bezier(0.4, 0.0, 0.0, 1);
$ease-in: cubic-bezier(0.0, 0.0, 0.2, 1);

*,
*:before,
*:after {
  box-sizing: border-box;
}

body {
  font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background: darken($xlt-gray, 3%);
  height: 100vh;
  display: flex;
}

.grid-view {
  transform: scale(.75);
}

.block-wrap {
  width: $container-size;
  height: $container-size;
  background: $xlt-gray;
  border-bottom: 2px solid darken($xlt-gray, 15%);
  box-shadow:
      inset 0 1px 0 lighten($xlt-gray, 5%),
      0 8px 8px -8px darken($xlt-gray, 15%),
      0 12px 12px -8px darken($xlt-gray, 5%);
  display: flex;
  position: relative;
  overflow: hidden;
  justify-content: center;
  border-radius: 8px;
  margin: auto;
}


.block-col {
  display: flex;
  height: 100%;
  margin: 0 12px;
  width: $block-size; //holds width when blocks are pos:abs
  flex-shrink: 0;
}

.block {
  height: $block-size;
  width: 100%;
  border-radius: 8px;
  margin: auto 0;
  position: relative;
  will-change: transform;
  &:not(.block--active) {
    cursor: pointer;
    &:hover, &.fake-hover {
      transform: translateY(-$hoverTranslate);
      &:after {
        // prevents awkard jittering on hover
        content: "";
        display: block;
        position: absolute;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;
        transform: scale(1.1) translateY($hoverTranslate);
      }
    }
    &:active {
      transform: scale(0.9) translateY(-$hoverTranslate);
    }
  }

  &--active {
    position: absolute;
    left: 0;
    z-index: 1;
    height: 100%;
    width: 100%;
  }

  &--transition {
    transition: transform 0.185s $ease;
  }
}

.block-content {
  display: none;
  padding: 24px;
  .block--active & {
    display: block;
  }
}

.block-content__header {
  background: rgba(black, .1);
  padding: 24px;
  margin: -24px -24px 24px;
  overflow: hidden;
}

.block-content__header__text {
  will-change: transform;
  margin: 0;
  opacity: 0;
  font-size: 2em;
  .block--active & {
    animation: content-in .225s $ease-in forwards; 
    animation-delay: .15s;
  }
}

.block-content__body {
  will-change: transform;
  opacity: 0;
  font-size: 18px;
  line-height: 1.333;
  animation: content-in .245s $ease-in forwards; 
  animation-delay: .1s;
  margin: 0 0 20px;
}

.block-content__button {
    font-weight: bold;
    background: rgba(255, 255, 255, .25);
    display: inline-block;
    padding: 16px;
    border-radius: 4px;
    color: rgba(#fff, .85);
    animation: button-in .245s $ease-in forwards; 
    animation-delay: .2s;
    opacity: 0;
    cursor: pointer;
}

@keyframes content-in {
  0% {
    opacity: 0;
    transform: translateY(128px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes button-in {
  0% {
    opacity: 0;
    transform: translateY(64px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}


@mixin colored($color) {
  background: $color;
  color: darken($color, 45%);
  border-top: 2px solid lighten($color, 10%);

  &:not(.block--active) {
    border-bottom: 2px solid darken($color, 10%);
    box-shadow:
      0 8px 8px -8px darken($color, 15%),
      0 12px 12px -8px rgba($color, 0.4);
  }

  &.block--active {
    background: desaturate(lighten($color, 37.5%), 40%);
  }
  
  .block-content__header {
    background: $color;
  }
  
  .block-content__button {
    background: $color;
    border-bottom: 2px solid darken($color, 10%);
    border-top: 2px solid lighten($color, 10%);
  }
}

.r {
  @include colored($red);
}

.b {
  @include colored($blue);
}

.y {
  @include colored($yellow);
}
!

JS 

              
                const ACTIVE_CLASS = "block--active";
const TRANSITION_CLASS = "block--transition";

const getTransforms = (a, b) => {
  const scaleY = a.height / b.height;
  const scaleX = a.width / b.width;

  // dividing by 2 centers the transform since the origin
  // is centered not top left
  const translateX = a.left + a.width / 2 - (b.left + b.width / 2);
  const translateY = a.top + a.height / 2 - (b.top + b.height / 2);

  // nothing particularly clever here, just using the
  // translate amount to estimate a rotation direction/amount.
  // ends up feeling pretty natural to me.
  const rotate = translateX;

  return [
    `translateX(${translateX}px)`,
    `translateY(${translateY}px)`,
    `rotate(${rotate}deg)`,
    `scaleY(${scaleY})`,
    `scaleX(${scaleX})`
  ].join(" ");
};

const animate = (block, transforms, oldTransforms) => {
  block.style.transform = transforms;
  block.getBoundingClientRect(); // force redraw
  block.classList.add(TRANSITION_CLASS);
  block.style.transform = oldTransforms;
  block.addEventListener(
    "transitionend",
    () => {
      block.removeAttribute("style");
    },
    { once: true }
  );
};

[...document.querySelectorAll(".block")].forEach(block => {
  const buttonForBlock = block.querySelector(".block-content__button");
  block.addEventListener("click", event => {
    if (
      block.classList.contains(ACTIVE_CLASS) &&
      event.target !== buttonForBlock
    ) {
      return;
    }

    block.classList.remove(TRANSITION_CLASS);
    const inactiveRect = block.getBoundingClientRect();
    const oldTransforms = block.style.transform;

    block.classList.toggle(ACTIVE_CLASS);
    const activeRect = block.getBoundingClientRect();
    const transforms = getTransforms(inactiveRect, activeRect);

    animate(block, transforms, oldTransforms);
  });
});
!
999px

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