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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>

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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.

Vendor Prefixing

About Vendor Prefixing

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-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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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="control">
  <button id="toggle">Toggle Theme</button>
</div>

<ul id="list">
  <li style="--view-transition-name: item-1; --index: 1;"><img src="https://picsum.photos/800/600?random=1" alt=""></li>
  <li style="--view-transition-name: item-2; --index: 2;"><img src="https://picsum.photos/800/600?random=2" alt=""></li>
  <li style="--view-transition-name: item-3; --index: 3;"><img src="https://picsum.photos/800/600?random=3" alt=""></li>
  <li style="--view-transition-name: item-4; --index: 4;"><img src="https://picsum.photos/800/600?random=4" alt=""></li>
  <li style="--view-transition-name: item-5; --index: 5;"><img src="https://picsum.photos/800/600?random=5" alt=""></li>
  <li style="--view-transition-name: item-6; --index: 6;"><img src="https://picsum.photos/800/600?random=6" alt=""></li>
  <li style="--view-transition-name: item-7; --index: 7;"><img src="https://picsum.photos/800/600?random=7" alt=""></li>
  <li style="--view-transition-name: item-8; --index: 8;"><img src="https://picsum.photos/800/600?random=8" alt=""></li>
  <li style="--view-transition-name: item-9; --index: 9;"><img src="https://picsum.photos/800/600?random=9" alt=""></li>
  <li style="--view-transition-name: item-10; --index: 10;"><img src="https://picsum.photos/800/600?random=10" alt=""></li>
  <li style="--view-transition-name: item-11; --index: 11;"><img src="https://picsum.photos/800/600?random=11" alt=""></li>
  <li style="--view-transition-name: item-12; --index: 12;"><img src="https://picsum.photos/800/600?random=12" alt=""></li>
  <li style="--view-transition-name: item-13; --index: 13;"><img src="https://picsum.photos/800/600?random=13" alt=""></li>
  <li style="--view-transition-name: item-14; --index: 14;"><img src="https://picsum.photos/800/600?random=14" alt=""></li>
  <li style="--view-transition-name: item-15; --index: 15;"><img src="https://picsum.photos/800/600?random=15" alt=""></li>
  <li style="--view-transition-name: item-16; --index: 16;"><img src="https://picsum.photos/800/600?random=16" alt=""></li>
  <li style="--view-transition-name: item-17; --index: 17;"><img src="https://picsum.photos/800/600?random=17" alt=""></li>
  <li style="--view-transition-name: item-18; --index: 18;"><img src="https://picsum.photos/800/600?random=18" alt=""></li>
  <li style="--view-transition-name: item-19; --index: 19;"><img src="https://picsum.photos/800/600?random=19" alt=""></li>
  <li style="--view-transition-name: item-20; --index: 20;"><img src="https://picsum.photos/800/600?random=20" alt=""></li>
</ul>
<div class="tutorials">
  <a href="https://s.juejin.cn/ds/idkRes2Y/" target="_blank">
    <svg t="1696988571607" class="icon" viewBox="0 0 1024 1024" version="1.1" xmlns="http://www.w3.org/2000/svg" p-id="4422" width="200" height="200"><path d="M924.8 576.64v-115.2c12.8-13.44 13.44-26.88 12.8-34.56-3.2-30.08-36.48-42.24-47.36-46.72-79.36-30.08-226.56-89.6-307.84-122.88-49.28-24.32-65.28-19.84-113.28-0.64-12.8 5.12-224.64 83.84-306.56 117.76-44.8 18.56-51.2 46.08-51.2 61.44 0 25.6 17.92 48.64 50.56 62.08L259.84 537.6v257.28l8.32 8.32c3.84 3.84 91.52 92.16 252.16 92.16 150.4 0 236.16-88.96 240-92.8l7.68-8.32V540.16l36.48-15.36-1.28 52.48-29.44 49.28 88.96 84.48 98.56-85.76-36.48-48.64zM710.4 771.2c-22.4 18.56-88.96 67.2-190.08 67.2-111.36 0-179.84-48.64-202.88-67.2V561.28l144.64 58.88h0.64c46.08 17.28 81.28 16 125.44-3.2l122.24-51.84v206.08z m154.24-138.24l-17.92-16.64 13.44-22.4 2.56-102.4c4.48-14.08-0.64-25.6-8.32-32-7.68-7.04-21.76-11.52-36.48-2.56L565.12 563.84c-30.08 13.44-49.92 14.08-81.92 2.56l-298.88-121.6c-7.68-3.2-12.16-6.4-14.08-8.96 1.92-1.92 6.4-5.12 14.72-8.96 81.92-33.92 302.72-116.48 305.28-117.12h0.64c38.4-15.36 38.4-15.36 67.2-0.64l1.92 0.64c80.64 32.64 226.56 92.16 307.2 122.88v163.2l16 21.12-18.56 16z" p-id="4423"></path></svg>
  </a>
  
</div>
!

CSS 

              
                @layer reset, base, form, layout, transitions;

@layer transitions {
  @keyframes zoomOut {
    from {
      opacity: 1;
    }

    50% {
      opacity: 0;
      transform: scale3d(0.3, 0.3, 0.3);
    }

    to {
      opacity: 0;
    }
  }
  @keyframes zoomIn {
    from {
      opacity: 0;
      transform: scale3d(0.3, 0.3, 0.3);
    }

    50% {
      opacity: 1;
    }
  }
  @keyframes clip {
    from {
      clip-path: circle(0% at var(--x) var(--y));
    }
    to {
      clip-path: circle(100% at var(--x) var(--y));
    }
  }
  html {
    background-color: #fff;
    color: #333;
    color-scheme: light;

    & img {
      border: 2px solid #333;
      transition: all 0.2s linear;
    }

    &.darker {
      background-color: #000;
      color: #fff;
      color-scheme: dark;

      & img {
        border-color: #fefefe;
        filter: brightness(0.5) saturate(0.5);
      }
    }
  }

  li {
    view-transition-name: var(--view-transition-name);
  }

  ::view-transition-old(root) {
    animation: none;
  }
  ::view-transition-new(root) {
    mix-blend-mode: normal;
    animation: clip 0.5s ease-in;
  }
}

@layer layout {
  ul {
    padding: 1rem;
    display: grid;
    grid-template-columns: repeat(
      auto-fit,
      minmax(min(100% - 2rem, 280px), 1fr)
    );
    gap: 1rem;

    & img {
      aspect-ratio: 16 / 9;
      border-radius: 6px;
    }
  }
}

@layer form {
  .control {
    display: grid;
    padding: 1rem;
    margin-inline: auto;
  }

  button {
    --background-color: #42b72a;
    --border-color: transparent;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    text-decoration: none;
    white-space: nowrap;
    transition: 200ms cubic-bezier(0.08, 0.52, 0.52, 1) background-color,
      200ms cubic-bezier(0.08, 0.52, 0.52, 1) box-shadow,
      200ms cubic-bezier(0.08, 0.52, 0.52, 1) transform;
    color: #fff;
    background-color: var(--background-color);
    border: none;
    border-color: var(--border-color);
    border-radius: 4px;
    font-size: 18px;
    padding-block: 0;
    padding-inline: 16px;
    min-block-size: 3rem;
    font-weight: 700;
    margin-inline: auto;
    transition: .3s;
  transform: scale(1);
    &:hover {
      --background-color: #36a420;
      --border-color: #36a420;
    }
  }
}

@layer reset {
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }

  ul {
    list-style: none outside none;
  }

  img {
    display: block;
    max-width: 100%;
    height: auto;
    object-fit: cover;
    object-position: center;
  }
}

@layer base {
  body {
    width: 100vw;
    min-height: 100vh;
    font-family: "Exo", "Bungee Shade", cursive, Arial, sans-serif;
    display: grid;
    align-content: start;
  }
  @media (prefers-reduced-motion: reduce) {
    *,
    ::before,
    ::after {
      animation-delay: -1ms !important;
      animation-duration: 1ms !important;
      animation-iteration-count: 1 !important;
      background-attachment: initial !important;
      scroll-behavior: auto !important;
      transition-duration: 0s !important;
      transition-delay: 0s !important;
    }
  }
  
  .tutorials {
    position: fixed;
    bottom: 1rem;
    right: 1rem;
    z-index: 9999;
    width: 64px;
    aspect-ratio: 1;
    border-radius: 50%;
    background: #3f517e;
    padding: .5rem;
    display: grid;
    place-content: center;
    transition: all .28s linear;
    
    &:hover {
      background:#4161b2;
    }
    
    & svg {
      display: block;
      width: 100%;
      height: 100%;
      filter: invert(1);
    }
  }
}
!

JS 

              
                const root = document.documentElement;
const toggleButton = document.getElementById('toggle');
const list = document.getElementById('list');
const items = document.querySelectorAll("#list > li");

items.forEach(item => {
  const transitionStyle = document.createElement("style");
  const viewTransitionName = getComputedStyle(item).getPropertyValue("--view-transition-name");
  const index = getComputedStyle(item).getPropertyValue("--index");
  item.appendChild(transitionStyle);
  transitionStyle.innerHTML = `
        @media (prefers-reduced-motion: no-preference) {
            ::view-transition-old(${viewTransitionName}) {
                animation: zoomOut 200ms ease-out forwards;
            }
        
            ::view-transition-new(${viewTransitionName}) {
                animation: 
                  zoomIn 400ms ease-in normal forwards;
            }
        }

        ::view-transition-group(${viewTransitionName}) {
            animation-delay: ${index * 20}ms;
        }
    `;
})


toggleButton.addEventListener('click', (etv)=>{
  root.style.setProperty(`--x`, `${etv.clientX}px`);
  root.style.setProperty(`--y`, `${etv.clientY}px`);
  viewTransition(()=>{
    root.classList.toggle('darker');
  })
})

list.addEventListener('click', (etv) => {
  const item = etv.target.parentElement;
  viewTransition(()=>{
    item.remove();
  })
})

function viewTransition(fn, params) {
  if (document.startViewTransition) {
    document.startViewTransition(() => fn(params));
  } else {
    fn(params);
  }
}
!
999px

Console