freeCodeCamp/curriculum/challenges/chinese/01-responsive-web-design/applied-visual-design/make-a-css-heartbeat-using-an-infinite-animation-count.chinese.md

id, title, challengeType, videoUrl, localeTitle

id	title	challengeType	videoUrl	localeTitle
587d78a8367417b2b2512ae4	Make a CSS Heartbeat using an Infinite Animation Count	0		使用无限动画计数制作CSS心跳

Description

这是一个带有animation-iteration-count属性的连续动画示例，该属性使用您在之前的挑战中设计的心脏。一秒长的心跳动画由两个动画片段组成。的heart元件（包括:before和:after片）的动画使用改变大小transform特性，并且背景div是动画使用改变其颜色background属性。

Instructions

通过为back类和heart类添加animation-iteration-count属性并将值设置为无限来保持心脏跳动。 heart:before和heart:after选择器heart:after不需要任何动画属性。

Tests

tests:
  - text: <code>heart</code>类的<code>animation-iteration-count</code>属性应具有无限值。
    testString: 'assert($(".heart").css("animation-iteration-count") == "infinite", "The <code>animation-iteration-count</code> property for the <code>heart</code> class should have a value of infinite.");'
  - text: <code>back</code>类的<code>animation-iteration-count</code>属性应具有无限值。
    testString: 'assert($(".back").css("animation-iteration-count") == "infinite", "The <code>animation-iteration-count</code> property for the <code>back</code> class should have a value of infinite.");'

Challenge Seed

<style>
  .back {
    position: fixed;
    padding: 0;
    margin: 0;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: white;
    animation-name: backdiv;
    animation-duration: 1s;

  }

  .heart {
    position: absolute;
    margin: auto;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    background-color: pink;
    height: 50px;
    width: 50px;
    transform: rotate(-45deg);
    animation-name: beat;
    animation-duration: 1s;

  }
  .heart:after {
    background-color: pink;
    content: "";
    border-radius: 50%;
    position: absolute;
    width: 50px;
    height: 50px;
    top: 0px;
    left: 25px;
  }
  .heart:before {
    background-color: pink;
    content: "";
    border-radius: 50%;
    position: absolute;
    width: 50px;
    height: 50px;
    top: -25px;
    left: 0px;
  }

  @keyframes backdiv {
    50% {
      background: #ffe6f2;
    }
  }

  @keyframes beat {
    0% {
      transform: scale(1) rotate(-45deg);
    }
    50% {
      transform: scale(0.6) rotate(-45deg);
    }
  }

</style>
<div class="back"></div>
<div class="heart"></div>

Solution

// solution required