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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Adding Classes

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About the <head>

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. If you need things in the <head> of the document, put that code here.

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Insecure Resource

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CSS

About CSS Preprocessors

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

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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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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HTML 

              
                <div class="container">
  <div class="dummy-text">
    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Sunt temporibus necessitatibus quasi minus. Quisquam nulla debitis odio inventore natus molestias consectetur dolorum incidunt, tenetur iure exercitationem, quibusdam dolores fugit harum.</p>
    <p>In quo est autem esse beatae dolorem architecto, voluptates vel quia culpa totam laudantium officia. Excepturi qui cum impedit ad corrupti quaerat quis, vero itaque ratione quia culpa, obcaecati numquam?</p>
    <p>Ducimus dignissimos adipisci similique assumenda, doloremque minima explicabo alias accusamus sequi cumque aut veritatis facilis, illo voluptatum expedita ea corporis, modi possimus amet esse odit rem provident eveniet consequatur? Quo.</p>
    <p>Impedit temporibus quam molestias eveniet voluptate dignissimos incidunt voluptatem nam quia, perferendis, inventore dolore quasi ut eos, ad accusamus id quidem facere exercitationem veniam magnam aperiam aspernatur blanditiis accusantium? Sapiente?</p>
    <p>Sit deleniti vero dignissimos officia sapiente. Est, molestias nemo eveniet rerum ab adipisci eius doloremque quibusdam mollitia eos reprehenderit atque labore amet in nesciunt magni error nulla ad a esse!</p>
    <p>Id doloribus enim harum, laudantium dolor dignissimos deserunt magni sunt illo voluptates? Quam labore ipsa consequatur! Dolore soluta corrupti accusantium consequatur, quasi neque quidem facere exercitationem, reiciendis rem nemo laborum?</p>
    <p>Ipsam voluptatibus beatae cumque soluta, ab nesciunt quas? Cupiditate ex dolorum, harum numquam fuga iste natus quae aut tempore laboriosam perferendis voluptate magni fugiat maxime eveniet, eum velit quaerat suscipit.</p>
    <p>Iure hic cupiditate consequuntur assumenda aut numquam dolorum, quod totam enim architecto commodi beatae repellendus, voluptatibus porro nam! Illo, aliquam provident! Voluptates quibusdam in autem saepe aliquid sequi totam recusandae?</p>
    <p>Cum atque blanditiis esse nisi necessitatibus eos optio, ab temporibus nulla, eius quia harum ipsa repudiandae illo maxime. Officiis assumenda doloribus corporis aperiam autem libero cupiditate earum eius magni exercitationem?</p>
    <p>Delectus quos fuga libero tempora ipsum saepe, quasi tempore neque debitis eius voluptate recusandae. Quod ipsum explicabo nemo dolor! Similique reiciendis ut perferendis alias rerum odit, deserunt nulla. Impedit, minima!</p>
  </div>

  <dialog id="cookie-box" popover="manual">
    <div class="cookie-box-inner">
      <div class="cookie-box-title">Cookie Consent</div>

      <div class="cookie-box-content">
        <p>A sample cookie-consent box created with the dialog element and the popover API. Below is a dummy button that close the cookie box.</p>
      </div>

      <div class="cookie-box-footer">
        <div class="btn-grp">
          <button id="accept-cookies" popovertarget="cookie-box" popovertargetaction="hide">Accept Cookies</button>

          <button id="close-cookie-box" popovertarget="cookie-box" popovertargetaction="hide">Close</button>
        </div>
      </div>
    </div>
  </dialog>

  <button id="open-cookie-box" popovertarget="cookie-box" popovertargetaction="show">Open Cookie box</button>
</div>
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CSS 

              
                @import url('https://fonts.googleapis.com/css2?family=Flow+Block&display=swap');

:root {
  --base-hue: 175deg;
  --body-bg-color: hsl(var(--base-hue) 95% 90%);
  --body-text-color: hsl(var(--base-hue) 15% 40%);
  --popover-bg-color: hsl(var(--base-hue) 95% 99%);
  --popover-text-color: hsl(var(--base-hue) 15% 25%);
  --popover-border-color: hsl(var(--base-hue) 30% 60%);
}

body {
  font: 1em/1.6 sans-serif;
  background-color: var(--body-bg-color);
  color: var(--body-text-color);
  min-height: 100vh;
}

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

.container {
  padding: 2em;
  max-width: 500px;
  height: 100%;
}

p + p {
  margin-top: 1em;
}

button {
  padding: .25em .75em;
  cursor: pointer;
  font: inherit;
  color: inherit;
}

.dummy-text {
  font-family: "Flow Block", sans-serif;
}

.main-nav > ul {
  display: flex;
  gap: 1em;
}

#cookie-box {
  color: var(--popover-text-color);
  position: fixed;
  inset: unset;
  bottom: 1em;
  right: 1em;
  max-width: 350px;
  width: 100%;
  border: 2px solid var(--popover-border-color);
  box-shadow: 0 0 .5em .25em hsl(0 0% 0% / 10%);
  border-radius: .5em;
  background-color: var(--popover-bg-color);
  color: var(--popover-text-color);
}

.cookie-box-inner {
  position: relative;
  padding: 1em;
}

#open-cookie-box {
  position: fixed;
  bottom: 1em;
  right: 1em;
}

#close-cookie-box {
  font-size: .75em;
  position: absolute;
  top: .25em;
  right: .25em;
}

.cookie-box-title {
  font-weight: bold;
}

.cookie-box-title + .cookie-box-content,
.cookie-box-content + .cookie-box-footer {
  margin-top: 1em;
}

.btn-grp {
  display: flex;
  gap: 1em;
}
!

JS 

              
                const cookieBox = document.querySelector("#cookie-box");
const acceptCookiesBtn = document.querySelector("#accept-cookies");
const closeCookieBoxBtn = document.querySelector("#close-cookie-box");
const openCookieBoxBtn = document.querySelector("#open-cookie-box");

// Keep the cookie consent box opened iniitally.
cookieBox.showPopover();

acceptCookiesBtn.addEventListener("click", () => {
  console.log("Cookies accepted!");
});

acceptCookiesBtn.addEventListener("click", () => {
  console.log("Cookie consent box closed.");
});

cookieBox.addEventListener("toggle", (e) => {
  if (e.newState === "open") {
    openCookieBoxBtn.style.display = "none";
  } else {
    openCookieBoxBtn.style.display = "block";
  }
});
!
999px

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