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HTML

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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HTML 

              
                <h1>Modals the <em>easy</em> way</h1>
<p>Lorem ipsum dolor sit, amet consectetur adipisicing elit. Impedit alias dicta quibusdam cumque ipsa ipsum reiciendis animi, officia provident veniam quis delectus minima earum suscipit ea, beatae vitae ipsam nemo.</p>
<p>Alias, architecto sapiente nostrum id, sed explicabo numquam aspernatur ratione qui excepturi repellat porro culpa molestiae? Culpa dolorem commodi cupiditate, eos deleniti similique repellendus nam velit natus a soluta et.</p>
<p>Fugiat ratione impedit officiis? Eligendi sapiente culpa tenetur esse quo reiciendis illum vero nisi ullam consequatur illo molestiae, nihil eaque. Esse asperiores tenetur natus! Quo asperiores molestias sed assumenda alias.</p>
<p>Sequi quo animi, nostrum laboriosam veritatis consequatur. Eos cumque unde porro explicabo provident, possimus alias magni pariatur quis consequuntur voluptatum? Debitis necessitatibus facilis fugiat repudiandae nobis neque nam, vel odio?</p>
<button class="button open-button">open modal</button>

<dialog class="modal" id="modal">
  <h2>An interesting title</h2>
  <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Rerum esse nisi, laboriosam illum temporibus ipsam?</p>
  <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Atque, quo.</p>
  <button class="button close-button">close modal</button>
  <form class="form" method="dialog">
    <label>Your name <input type="text"></label>
    <label>Your email <input type="email"></label>
    <button class="button" type="submit">submit form</button>
  </form>

</dialog>

<!--   
  <form class="form" method="dialog">
    <label>Your name <input type="text"></label>
    <label>Your email <input type="email"></label>
    <button class="button" type="submit">submit form</button>
  </form>-->
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CSS 

              
                .modal {
  // padding: 1em;
  max-width: 50ch;
  // border: 0;
  // box-shadow: 0 0 1em rgb(0 0 0 / .3);

  & > * {
    margin: 0 0 0.5rem 0;
  }
}

.modal::backdrop {
  background: rgb(0 0 0 / 0.4);
}

/* extra styling */

body {
  min-height: 100vh;
  margin: 2rem;
  font-family: system-ui;
  font-size: 1.25rem;
  line-height: 1.5;
  color: var(--gray-8);
  // background-image: url('https://images.unsplash.com/photo-1644242629712-943ae5c8c4f3?crop=entropy&cs=srgb&fm=jpg&ixid=MnwxNDU4OXwwfDF8cmFuZG9tfHx8fHx8fHx8MTY0Njc1MjQxNA&ixlib=rb-1.2.1&q=85');
  // background-size: cover;
}

h1 em {
  color: var(--cyan-9);
  text-decoration: underline;
  text-underline-offset: 0.25em;
}

.button {
  border: 0;
  cursor: pointer;
  background: var(--gray-8);
  color: var(--gray-2);
  font-weight: 700;
  padding: var(--size-2) var(--size-4);
}

.button:hover,
.button:focus {
  background: var(--cyan-9);
}

form {
  display: grid;
  gap: 1em;
}
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JS 

              
                const modal = document.querySelector("#modal");
const openModal = document.querySelector(".open-button");
const closeModal = document.querySelector(".close-button");

openModal.addEventListener("click", () => {
  modal.showModal();
});

closeModal.addEventListener("click", () => {
  modal.close();
});
!
999px

Console