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HTML 

              
                <main>
  <article>
    <h1>Pop-up Discount Code</h1>
    <p>
      Lorem ipsum dolor sit amet consectetur, adipisicing elit. Nostrum nam
      sint sed modi dolor veniam repudiandae, et quasi unde quis voluptatum
      iure accusantium quam quod ducimus itaque eligendi eius, natus?
    </p>
    <button class="button ripple" popovershowtarget="code-pop-up">
      Reveal Code
    </button>
    <div id="code-pop-up" class="balloon" popover>
      <div class="balloon__content">
        <div class="balloon__handle"></div>
        <code>my-first-pop-up</code>
        <button class="button ripple" popoverhidetarget="code-pop-up">Hide Code</button>
      </div>
    </div>
  </article>
</main>
!

CSS 

              
                @layer normalize, open-props, base, mdl, demo;

@layer demo {
  [popover] {
    padding: var(--size-4);
    width: var(--size);
  }
  [popover] {
    animation: exit-animation 250ms ease-out both;
    transform: translate(-50%, -50%) translateX(0) scale(1);
    box-shadow: var(--shadow-5);
    position: fixed;
    top: 50%;
    left: 50%;
    margin: 0;
  }

  [popover]:open {
    animation: entry-animation 1s ease-in both;
  }

  @keyframes exit-animation {
    100% {
      transform: translate(-50%, -50%) translateY(-100vh) scale(0);
    }
  }

  @keyframes entry-animation {
    0% {
      transform: translate(-50%, -50%) translateY(100vh) scale(0);
    }
  }

  [popover]::backdrop {
    background: hsl(0 10% 10%/ 0.35);
    opacity: 0;
    transition: all 1s;
    backdrop-filter: blur(2px);
  }

  [popover]:open::backdrop {
    opacity: 1;
    transition: all 1s;
  }
}

@layer base {
  :root {
    --primary-color: hsl(320 100% 50% / 0.75);
    --shine: hsl(0 0% 100% / 0.35);
    --speed: 1s;
    --size: clamp(200px, 10vw, 10rem);
  }

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

  body {
    display: grid;
    place-items: center;
    min-height: 100vh;
    font-family: "Google Sans", sans-serif, system-ui;
    align-content: center;
  }

  :where([popover]) {
    margin: auto;
    border-width: initial;
    border-style: solid;
  }
  code {
    background: var(--gray-2);
    color: var(--md-sys-color-primary);
    font-weight: var(--font-weight-9);
  }

  article {
    padding: var(--size-4);
    max-inline-size: var(--size-content-2);
  }

  article p {
    margin-bottom: var(--size-4);
  }
}

@layer balloon {
  .balloon {
    overflow: visible;
    /*width: var(--size);*/
    aspect-ratio: 0.8 / 1;
    height: auto;
    background: var(--primary-color);
    border-radius: 50% 50% 50% 50% / 45% 45% 55% 55%;
    /*animation: float calc(var(--d, 1) * 1s) calc(var(--delay, 0) * -1s) infinite linear both;*/
  }

  .balloon:before {
    content: "";
    position: absolute;
    width: 20%;
    height: 30%;
    background: blue;
    top: 8%;
    left: 16%;
    border-radius: 50%;
    transform: rotate(40deg);
    background: var(--shine);
  }

  .balloon__content {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    width: 100%;
    flex-direction: column;
    gap: var(--size-4);
    font-weight: var(--font-weight-6);
  }

  .balloon__handle {
    --chord: hsl(45, 100%, 40%);
    width: 2%;
    height: 60%;
    background: var(--chord);
    top: 100%;
    left: 50%;
    transform: translate(-50%, 0);
    position: absolute;
  }
  .balloon__handle:before,
  .balloon__handle:after {
    content: "";
    position: absolute;
    height: 5%;
    transform: translate(-50%, 0);
    border-radius: 25% / 50%;
    left: 50%;
  }

  .balloon__handle:before {
    top: 0;
    background: var(--chord);
    width: 500%;
  }

  .balloon__handle:after {
    top: 5%;
    background: var(--primary-color);
    width: 700%;
  }
}
!

JS
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