HTML&CSS：翻书加载效果

效果演示

这段 HTML 和 CSS 代码创建了一个简单的翻书加载效果

HTML

<div class="loader">
  <div>
    <ul>
      <li>
        <svg fill="currentColor" viewBox="0 0 90 120">
          <path d="M90,0 L90,120 L11,120 C4.92486775,120 0,115.075132 0,109 L0,11 C0,4.92486775 4.92486775,0 11,0 L90,0 Z M71.5,81 L18.5,81 C17.1192881,81 16,82.1192881 16,83.5 C16,84.8254834 17.0315359,85.9100387 18.3356243,85.9946823 L18.5,86 L71.5,86 C72.8807119,86 74,84.8807119 74,83.5 C74,82.1745166 72.9684641,81.0899613 71.6643757,81.0053177 L71.5,81 Z M71.5,57 L18.5,57 C17.1192881,57 16,58.1192881 16,59.5 C16,60.8254834 17.0315359,61.9100387 18.3356243,61.9946823 L18.5,62 L71.5,62 C72.8807119,62 74,60.8807119 74,59.5 C74,58.1192881 72.8807119,57 71.5,57 Z M71.5,33 L18.5,33 C17.1192881,33 16,34.1192881 16,35.5 C16,36.8254834 17.0315359,37.9100387 18.3356243,37.9946823 L18.5,38 L71.5,38 C72.8807119,38 74,36.8807119 74,35.5 C74,34.1192881 72.8807119,33 71.5,33 Z"></path>
        </svg>
      </li>
      <li>
        <svg fill="currentColor" viewBox="0 0 90 120">
          <path d="M90,0 L90,120 L11,120 C4.92486775,120 0,115.075132 0,109 L0,11 C0,4.92486775 4.92486775,0 11,0 L90,0 Z M71.5,81 L18.5,81 C17.1192881,81 16,82.1192881 16,83.5 C16,84.8254834 17.0315359,85.9100387 18.3356243,85.9946823 L18.5,86 L71.5,86 C72.8807119,86 74,84.8807119 74,83.5 C74,82.1745166 72.9684641,81.0899613 71.6643757,81.0053177 L71.5,81 Z M71.5,57 L18.5,57 C17.1192881,57 16,58.1192881 16,59.5 C16,60.8254834 17.0315359,61.9100387 18.3356243,61.9946823 L18.5,62 L71.5,62 C72.8807119,62 74,60.8807119 74,59.5 C74,58.1192881 72.8807119,57 71.5,57 Z M71.5,33 L18.5,33 C17.1192881,33 16,34.1192881 16,35.5 C16,36.8254834 17.0315359,37.9100387 18.3356243,37.9946823 L18.5,38 L71.5,38 C72.8807119,38 74,36.8807119 74,35.5 C74,34.1192881 72.8807119,33 71.5,33 Z"></path>
        </svg>
      </li>
      <li>
        <svg fill="currentColor" viewBox="0 0 90 120">
          <path d="M90,0 L90,120 L11,120 C4.92486775,120 0,115.075132 0,109 L0,11 C0,4.92486775 4.92486775,0 11,0 L90,0 Z M71.5,81 L18.5,81 C17.1192881,81 16,82.1192881 16,83.5 C16,84.8254834 17.0315359,85.9100387 18.3356243,85.9946823 L18.5,86 L71.5,86 C72.8807119,86 74,84.8807119 74,83.5 C74,82.1745166 72.9684641,81.0899613 71.6643757,81.0053177 L71.5,81 Z M71.5,57 L18.5,57 C17.1192881,57 16,58.1192881 16,59.5 C16,60.8254834 17.0315359,61.9100387 18.3356243,61.9946823 L18.5,62 L71.5,62 C72.8807119,62 74,60.8807119 74,59.5 C74,58.1192881 72.8807119,57 71.5,57 Z M71.5,33 L18.5,33 C17.1192881,33 16,34.1192881 16,35.5 C16,36.8254834 17.0315359,37.9100387 18.3356243,37.9946823 L18.5,38 L71.5,38 C72.8807119,38 74,36.8807119 74,35.5 C74,34.1192881 72.8807119,33 71.5,33 Z"></path>
        </svg>
      </li>
      <li>
        <svg fill="currentColor" viewBox="0 0 90 120">
          <path d="M90,0 L90,120 L11,120 C4.92486775,120 0,115.075132 0,109 L0,11 C0,4.92486775 4.92486775,0 11,0 L90,0 Z M71.5,81 L18.5,81 C17.1192881,81 16,82.1192881 16,83.5 C16,84.8254834 17.0315359,85.9100387 18.3356243,85.9946823 L18.5,86 L71.5,86 C72.8807119,86 74,84.8807119 74,83.5 C74,82.1745166 72.9684641,81.0899613 71.6643757,81.0053177 L71.5,81 Z M71.5,57 L18.5,57 C17.1192881,57 16,58.1192881 16,59.5 C16,60.8254834 17.0315359,61.9100387 18.3356243,61.9946823 L18.5,62 L71.5,62 C72.8807119,62 74,60.8807119 74,59.5 C74,58.1192881 72.8807119,57 71.5,57 Z M71.5,33 L18.5,33 C17.1192881,33 16,34.1192881 16,35.5 C16,36.8254834 17.0315359,37.9100387 18.3356243,37.9946823 L18.5,38 L71.5,38 C72.8807119,38 74,36.8807119 74,35.5 C74,34.1192881 72.8807119,33 71.5,33 Z"></path>
        </svg>
      </li>
      <li>
        <svg fill="currentColor" viewBox="0 0 90 120">
          <path d="M90,0 L90,120 L11,120 C4.92486775,120 0,115.075132 0,109 L0,11 C0,4.92486775 4.92486775,0 11,0 L90,0 Z M71.5,81 L18.5,81 C17.1192881,81 16,82.1192881 16,83.5 C16,84.8254834 17.0315359,85.9100387 18.3356243,85.9946823 L18.5,86 L71.5,86 C72.8807119,86 74,84.8807119 74,83.5 C74,82.1745166 72.9684641,81.0899613 71.6643757,81.0053177 L71.5,81 Z M71.5,57 L18.5,57 C17.1192881,57 16,58.1192881 16,59.5 C16,60.8254834 17.0315359,61.9100387 18.3356243,61.9946823 L18.5,62 L71.5,62 C72.8807119,62 74,60.8807119 74,59.5 C74,58.1192881 72.8807119,57 71.5,57 Z M71.5,33 L18.5,33 C17.1192881,33 16,34.1192881 16,35.5 C16,36.8254834 17.0315359,37.9100387 18.3356243,37.9946823 L18.5,38 L71.5,38 C72.8807119,38 74,36.8807119 74,35.5 C74,34.1192881 72.8807119,33 71.5,33 Z"></path>
        </svg>
      </li>
      <li>
        <svg fill="currentColor" viewBox="0 0 90 120">
          <path d="M90,0 L90,120 L11,120 C4.92486775,120 0,115.075132 0,109 L0,11 C0,4.92486775 4.92486775,0 11,0 L90,0 Z M71.5,81 L18.5,81 C17.1192881,81 16,82.1192881 16,83.5 C16,84.8254834 17.0315359,85.9100387 18.3356243,85.9946823 L18.5,86 L71.5,86 C72.8807119,86 74,84.8807119 74,83.5 C74,82.1745166 72.9684641,81.0899613 71.6643757,81.0053177 L71.5,81 Z M71.5,57 L18.5,57 C17.1192881,57 16,58.1192881 16,59.5 C16,60.8254834 17.0315359,61.9100387 18.3356243,61.9946823 L18.5,62 L71.5,62 C72.8807119,62 74,60.8807119 74,59.5 C74,58.1192881 72.8807119,57 71.5,57 Z M71.5,33 L18.5,33 C17.1192881,33 16,34.1192881 16,35.5 C16,36.8254834 17.0315359,37.9100387 18.3356243,37.9946823 L18.5,38 L71.5,38 C72.8807119,38 74,36.8807119 74,35.5 C74,34.1192881 72.8807119,33 71.5,33 Z"></path>
        </svg>
      </li>
    </ul>
  </div><span>Loading</span></div>

• loader: 一个容器，用于包含加载动画。
• ul 和 li: 无序列表和列表项，用于布局加载动画中的各个部分。
• svg: 用于绘制加载动画中的图形元素。
• span: 显示加载文本。

CSS

.loader {
  --background: linear-gradient(135deg, #23C4F8, #275EFE);
  --shadow: rgba(39, 94, 254, 0.28);
  --text: #6C7486;
  --page: rgba(255, 255, 255, 0.36);
  --page-fold: rgba(255, 255, 255, 0.52);
  --duration: 3s;
  width: 200px;
  height: 140px;
  position: relative;
}

.loader:before, .loader:after {
  --r: -6deg;
  content: "";
  position: absolute;
  bottom: 8px;
  width: 120px;
  top: 80%;
  box-shadow: 0 16px 12px var(--shadow);
  transform: rotate(var(--r));
}

.loader:before {
  left: 4px;
}

.loader:after {
  --r: 6deg;
  right: 4px;
}

.loader div {
  width: 100%;
  height: 100%;
  border-radius: 13px;
  position: relative;
  z-index: 1;
  perspective: 600px;
  box-shadow: 0 4px 6px var(--shadow);
  background-image: var(--background);
}

.loader div ul {
  margin: 0;
  padding: 0;
  list-style: none;
  position: relative;
}

.loader div ul li {
  --r: 180deg;
  --o: 0;
  --c: var(--page);
  position: absolute;
  top: 10px;
  left: 10px;
  transform-origin: 100% 50%;
  color: var(--c);
  opacity: var(--o);
  transform: rotateY(var(--r));
  -webkit-animation: var(--duration) ease infinite;
  animation: var(--duration) ease infinite;
}

.loader div ul li:nth-child(2) {
  --c: var(--page-fold);
  -webkit-animation-name: page-2;
  animation-name: page-2;
}

.loader div ul li:nth-child(3) {
  --c: var(--page-fold);
  -webkit-animation-name: page-3;
  animation-name: page-3;
}

.loader div ul li:nth-child(4) {
  --c: var(--page-fold);
  -webkit-animation-name: page-4;
  animation-name: page-4;
}

.loader div ul li:nth-child(5) {
  --c: var(--page-fold);
  -webkit-animation-name: page-5;
  animation-name: page-5;
}

.loader div ul li svg {
  width: 90px;
  height: 120px;
  display: block;
}

.loader div ul li:first-child {
  --r: 0deg;
  --o: 1;
}

.loader div ul li:last-child {
  --o: 1;
}

.loader span {
  display: block;
  left: 0;
  right: 0;
  top: 100%;
  margin-top: 20px;
  text-align: center;
  color: var(--text);
}

@keyframes page-2 {
  0% {
    transform: rotateY(180deg);
    opacity: 0;
  }

  20% {
    opacity: 1;
  }

  35%, 100% {
    opacity: 0;
  }

  50%, 100% {
    transform: rotateY(0deg);
  }
}

@keyframes page-3 {
  15% {
    transform: rotateY(180deg);
    opacity: 0;
  }

  35% {
    opacity: 1;
  }

  50%, 100% {
    opacity: 0;
  }

  65%, 100% {
    transform: rotateY(0deg);
  }
}

@keyframes page-4 {
  30% {
    transform: rotateY(180deg);
    opacity: 0;
  }

  50% {
    opacity: 1;
  }

  65%, 100% {
    opacity: 0;
  }

  80%, 100% {
    transform: rotateY(0deg);
  }
}

@keyframes page-5 {
  45% {
    transform: rotateY(180deg);
    opacity: 0;
  }

  65% {
    opacity: 1;
  }

  80%, 100% {
    opacity: 0;
  }

  95%, 100% {
    transform: rotateY(0deg);
  }
}

• .loader: 定义了加载动画的容器样式，包括大小、位置、阴影等。
• .loader:before 和 .loader:after: 使用伪元素创建加载动画的阴影效果。
• .loader div: 设置了加载动画内部容器的样式，包括背景、阴影、3D 效果等。
• .loader div ul 和 .loader div ul li: 设置了列表和列表项的样式，用于布局加载动画中的各个页面图标。
• .loader div ul li svg: 设置了 SVG 图标的大小和显示方式。
• .loader span: 设置了加载文本的样式，包括位置、对齐方式和颜色。
• @keyframes: 定义了动画的关键帧，用于创建加载动画中页面翻转的效果。