如何制作鼠标悬浮后伸缩的搜索框

引言

许多博客都在使用的伸缩搜索框制作教程

成品展示（颜色自行搭配）

22222

初步布局

居中盒子&&初始化样式

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
		/* 初步布局 */
    body {
      margin: 0;
      background: linear-gradient(200deg, #f1b2ff, #ff80c6);
      height: 100vh;
    }

    .search-box {
      position: absolute;
      top: 50%;
      left: 50%;
      background: #fff;
    }
  </style>
</head>

<body>
  <div class="search-box">
    box
  </div>
</body>

</html>

1形态

盒子中间填入input和a标签作为按钮背景色为白色

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    body {
        /* 初步布局 */
      margin: 0;
      background: linear-gradient(200deg, #f1b2ff, #ff80c6);
      height: 100vh;
    }

       /* 居中设置背景色 */
    .search-box {
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      background: #fff;
    }
  </style>
</head>

<body>
  <div class="search-box" class="search-input">
    <input type="text">
    <a href="" class="search-btn">按钮</a>
  </div>
</body>

</html>

2形态

让外盒子box变得更胖更圆润

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    body {
      /* 初步布局 */
      margin: 0;
      background: linear-gradient(200deg, #f1b2ff, #ff80c6);
      height: 100vh;
    }

    .search-box {
      /* 居中设置背景色 */
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      background: #fff;

      /* 让他变胖变圆润一点 */
      height: 40px;
      padding: 10px;
      border-radius: 40px;
    }
  </style>
</head>

<body>
  <div class="search-box">
    <input type="text" class="search-input">
    <a href="" class="search-btn">按钮</a>
  </div>
</body>

</html>

3形态

初始化输入框/按钮的样式和引入图标，将input一开始状态设置为width 0

文字标签换成图标

引入cdn
设置标签

输入框居中

设置input输入框自带的内边距为0，边框和轮廓为none

内部文字为16px 行高和父盒子一样40px

（从父盒子的Y起始点和结束点平均增加上下间距,也就是把文字往中间挤压，使得最后input输入框的整体高度和父盒子高度一致，实现输入框文字居中，直接这样记，行高=盒高为文字居中，且一行的上下边距会将文字挤到中间）

按钮样式

由于按钮是行内元素，想要设置宽高是无效的，让他往右漂浮，此时宽高生效

使用弹性布局将i标签水平横向居中

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <link href="https://cdn.bootcdn.net/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet">
  <style>
    body {
      /* 初步布局 */
      margin: 0;
      background: linear-gradient(200deg, #f1b2ff, #ff80c6);
      height: 100vh;
    }

    .search-box {
      /* 居中设置背景色 */
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      background: #fff;

      /* 让他变胖变圆润一点 */
      height: 40px;
      padding: 10px;
      border-radius: 40px;
    }

    .search-input {
      padding: 0;
      border: none;
      outline: none;
      font-size: 16px;
      line-height: 40px;
      width: 0;
    }

    .search-btn {
      width: 40px;
      height: 40px;
      border-radius: 50%;
      float: right;
      display: flex;
      justify-content: center;
      align-items: center;
      cursor: pointer;
    }


  </style>
</head>

<body>
  <div class="search-box">
    <input type="text" class="search-input" placeholder="请输入内容">
    <a class="search-btn">
      <i class="fa fa-search"></i>
    </a>
  </div>
</body>

</html>

4形态

悬浮或点击时box大盒子时 input宽度200px，按钮背景色变化，分别增加transition过渡0.4s

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <link href="https://cdn.bootcdn.net/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet">
  <style>
    body {
      /* 初步布局 */
      margin: 0;
      background: linear-gradient(200deg, #f1b2ff, #ff80c6);
      height: 100vh;
    }

    .search-box {
      /* 居中设置背景色 */
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      background: #fff;

      /* 让他变胖变圆润一点 */
      height: 40px;
      padding: 10px;
      border-radius: 40px;
    }

    .search-input {
      padding: 0;
      border: none;
      outline: none;
      font-size: 16px;
      line-height: 40px;
      width: 0;
      transition: 0.4s;
    }

    .search-btn {
      width: 40px;
      height: 40px;
      border-radius: 50%;
      float: right;
      display: flex;
      justify-content: center;
      align-items: center;
      cursor: pointer;
      transition: 0.4s;
    }

    .search-box:hover .search-input {
      width: 200px;
    }

    .search-box:hover .search-btn {
      background: #b05824;
    }
  </style>
</head>

<body>
  <div class="search-box">
    <input type="text" class="search-input" placeholder="请输入内容">
    <a class="search-btn">
      <i class="fa fa-search"></i>
    </a>
  </div>
</body>

</html>