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HTML

              
                <input id="darkmode" type="checkbox"> <label for="darkmode">Dark Mode</label>

<h1>A minimal example</h1>

<p>Check the “dark mode” box above to switch the color scheme of the page. When picking colors, <a href="https://color.review/">make sure they’re high-contrast</a> so that people can read them. I find it easier to keep track of variables if they’re grouped alphabetically <em>and</em> conceptually, which is why I like <code>--colorBackground</code> and <code>--colorForeground</code>. It’s easy to keep all your color variables in one place and scan them quickly if you begin all of them with the common <code>--color</code> prefix.</p>
              
            
!

CSS

              
                :root {
  --colorBackground: white;
  --colorForeground: darkslategray;
  --colorLink: royalblue;
  --colorCode: crimson;
}

.dark {
  --colorBackground: black;
  --colorForeground: lightgray;
  --colorLink: cornflowerblue;
  --colorCode: lightpink;
}

body {
  background-color: var(--colorBackground);
  color: var(--colorForeground);
}

a {
  color: var(--colorLink);
}

code {
  color: var(--colorCode);
}
              
            
!

JS

              
                document.querySelector('#darkmode').addEventListener('change', function(event){
  document.querySelector('body').classList.toggle('dark');
});
              
            
!
999px

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