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HTML

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Adding Classes

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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

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Vendor Prefixing

About Vendor Prefixing

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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 

              
                <h2>CSS Toggles based slide (Pure CSS)</h2>

<div class="alert">Your browser does not support CSS Toggles, please upgrade to Chrome Canary 108+ and turn on Flag(`--enable-blink-features=CSSToggles`).</div>

<section>
  <div class="control">
    <div class="btn prev-slide" title="上一页">
      <svg class="icon" viewBox="0 0 1024 1024" version="1.1" xmlns="http://www.w3.org/2000/svg">
        <path d="M729.6 931.2l-416-425.6 416-416c9.6-9.6 9.6-25.6 0-35.2-9.6-9.6-25.6-9.6-35.2 0l-432 435.2c-9.6 9.6-9.6 25.6 0 35.2l432 441.6c9.6 9.6 25.6 9.6 35.2 0C739.2 956.8 739.2 940.8 729.6 931.2z" p-id="10915"></path>
      </svg>
    </div>
    <div class="btn next-slide" title="下一页">
      <svg class="icon" viewBox="0 0 1024 1024" version="1.1" xmlns="http://www.w3.org/2000/svg">
        <path d="M761.6 489.6l-432-435.2c-9.6-9.6-25.6-9.6-35.2 0-9.6 9.6-9.6 25.6 0 35.2l416 416-416 425.6c-9.6 9.6-9.6 25.6 0 35.2s25.6 9.6 35.2 0l432-441.6C771.2 515.2 771.2 499.2 761.6 489.6z" p-id="10760"></path>
      </svg>
    </div>
  </div>

  <div class="slide-content">
    <article>
      <div class="tips"></div>
      <img src="https://cdn.cdnjson.com/wx3.sinaimg.cn/mw690/90f78f62ly1fm3yd7emocj213i0qon73.jpg" alt="" loading="lazy">
    </article>
    <article>
      <div class="tips"></div>
      <img src="https://cdn.cdnjson.com/wx4.sinaimg.cn/mw1024/90f78f62ly1fvqpameuuwj20qo0zi10d.jpg" alt="" loading="lazy">
    </article>
    <article>
      <div class="tips"></div>
      <img src="https://cdn.cdnjson.com/wx2.sinaimg.cn/mw690/90f78f62ly1fmls4xf4w2j21400qoafa.jpg" alt="" loading="lazy">
    </article>
  </div>

  <div class="pagination">
    <div class="number" style="toggle-trigger: slides set 1">1</div>
    <div class="number" style="toggle-trigger: slides set 2">2</div>
    <div class="number" style="toggle-trigger: slides set 3">3</div>
  </div>
</section>
!

CSS 

              
                .alert {
  color: red;
  padding: 0 2em;
}

@supports (toggle-trigger: foo next) and (toggle-root: foo 3 at 1 cycle-on) {
  .alert {
    display: none;
  }
}

body {
  display: flex;
  flex-direction: column;
  align-items: center;
}

* {
  box-sizing: border-box;
}

img {
  max-width: 100%;
  display: block;
}

:root {
  --tips-size: 100px;
}

.btn {
  padding: 5px 10px;
  user-select: none;
  cursor: pointer;
}

section {
  margin-top: 20px;
  position: relative;
  width: 600px;
  aspect-ratio: 3 / 2;
  /* toggle-root: slides 3 at 1 sticky; */
  toggle-root: slides 3 at 1 cycle-on;
}

article {
  flex: 1 0 100%;
  transition: transform 0.3s ease-out;
  transform: translateX(var(--x, 0));
}

/* 第1页 */
article:nth-of-type(1):toggle(slides 1) {
  --x: 0%;
}

article:nth-of-type(1):toggle(slides 1) ~ article {
  --x: 0%;
}

article:nth-of-type(1):toggle(slides 2) {
  --x: -100%;
}

/* 第2页 */
article:nth-of-type(2):toggle(slides 2) {
  --x: -100%;
}

article:nth-of-type(2):toggle(slides 2) ~ article {
  --x: -100%;
}

/* 第3页 */
article:nth-of-type(3):toggle(slides 3),
article:nth-of-type(2):toggle(slides 3),
article:nth-of-type(1):toggle(slides 3) {
  --x: -200%;
}

/* 分页高亮 */
:toggle(slides 1) ~ .pagination .number:nth-of-type(1),
:toggle(slides 2) ~ .pagination .number:nth-of-type(2),
:toggle(slides 3) ~ .pagination .number:nth-of-type(3) {
  background-color: #fff;
  color: #333;
  transform: scale(1.3);
}

.next-slide {
  toggle-trigger: slides next;
}

.prev-slide {
  toggle-trigger: slides prev;
}

.slide-content {
  overflow: hidden;
  display: flex;
  width: 100%;
  aspect-ratio: 3 / 2;
  position: relative;
  border-radius: 10px;
  box-shadow: 2px 2px 8px rgba(0, 0, 0, 0.3);
}

/* tips */
article {
  counter-increment: count;
  overflow: hidden;
}

.tips:before {
  content: counters(count, ".", decimal);
  width: calc(var(--tips-size) / 2.81408534);
  height: calc(var(--tips-size) / 2.81408534);
  pointer-events: none;
  display: flex;
  justify-content: center;
  transform: translate(140%, 140%) rotate(45deg);
  transform-origin: 0 0;
}

.tips {
  position: absolute;
  top: 0;
  transform: translate(-50%, -50%) rotate(-45deg);
  position: absolute;
  top: 0;
  left: 0;
  width: var(--tips-size);
  height: var(--tips-size);
  color: #fff;
  font-size: 30px;
  background: rgba(46, 50, 51, 0.8);
  transition: --tips-size 0.3s;
  white-space: nowrap;
}

/* 分页 */
.icon {
  width: 64px;
  height: 64px;
  fill: #fff;
  transition: background 0.3s;
  border-radius: 999px;
  padding: 6px 0;
}

.icon:hover {
  background-color: rgba(0, 0, 0, 0.5);
}

.control {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 9;
  width: 100%;
  display: flex;
  justify-content: space-between;
}

.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 20;
  user-select: none;
}

.pagination .number {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  color: transparent;
  background-color: transparent;
  transition: 0.3s;
  margin-right: 10px;
  cursor: pointer;
  font-size: 12px;
  display: flex;
  justify-content: center;
  align-items: center;
  border: 1px solid #fff;
  box-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
}
!

JS 

              
                // No JS

let root = document.querySelector("section");
console.log("Get toggles \n", root.toggles.get("slides"));

root.addEventListener(
  "togglechange",
  function (e) {
    console.log("CSS toggle changed \n", e);
  },
  false
);
!
999px

Console