W3School TIY Editor

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<style>
body {
  font-family: Arial, Helvetica, sans-serif;
}

* {
  box-sizing: border-box;
}

/* 样式容器 */
.container {
  position: relative;
  border-radius: 5px;
  background-color: #f2f2f2;
  padding: 20px 0 30px 0;
}

/* 样式输入框和链接按钮 */
input,
.btn {
  width: 100%;
  padding: 12px;
  border: none;
  border-radius: 4px;
  margin: 5px 0;
  opacity: 0.85;
  display: inline-block;
  font-size: 17px;
  line-height: 20px;
  text-decoration: none; /* 移除锚文本下划线 */
}

input:hover,
.btn:hover {
  opacity: 1;
}

/* 为fb、twitter和google按钮添加适当的颜色 */
.fb {
  background-color: #3B5998;
  color: white;
}

.twitter {
  background-color: #55ACEE;
  color: white;
}

.google {
  background-color: #dd4b39;
  color: white;
}

/* 样式提交按钮 */
input[type=submit] {
  background-color: #04AA6D;
  color: white;
  cursor: pointer;
}

input[type=submit]:hover {
  background-color: #45a049;
}

/* 两列布局 */
.col {
  float: left;
  width: 50%;
  margin: auto;
  padding: 0 50px;
  margin-top: 6px;
}

/* 清除列后的浮动 */
.row:after {
  content: "";
  display: table;
  clear: both;
}

/* 垂直线 */
.vl {
  position: absolute;
  left: 50%;
  transform: translate(-50%);
  border: 2px solid #ddd;
  height: 175px;
}

/* 垂直线中的文本 */
.vl-innertext {
  position: absolute;
  top: 50%;
  transform: translate(-50%, -50%);
  background-color: #f1f1f1;
  border: 1px solid #ccc;
  border-radius: 50%;
  padding: 8px 10px;
}

/* 在中等和大屏幕上隐藏一些文本 */
.hide-md-lg {
  display: none;
}

/* 底部容器 */
.bottom-container {
  text-align: center;
  background-color: #666;
  border-radius: 0px 0px 4px 4px;
}

/* 响应式布局 - 当屏幕宽度小于650px时，将两列堆叠在一起而不是并排显示 */
@media screen and (max-width: 650px) {
  .col {
    width: 100%;
    margin-top: 0;
  }
  /* 隐藏垂直线 */
  .vl {
    display: none;
  }
  /* 在小屏幕上显示隐藏文本 */
  .hide-md-lg {
    display: block;
    text-align: center;
  }
}
</style>
</head>
<body>

<h2>社交登录表单</h2>
<p>调整浏览器窗口大小可查看响应式效果。当屏幕宽度小于 650 像素时，使两列上下堆叠而非并排显示。</p>

<div class="container">
  <form action="/action_page.php">
    <div class="row">
      <h2 style="text-align:center">Login with Social Media or Manually</h2>
      <div class="vl">
        <span class="vl-innertext">or</span>
      </div>

<div class="col">
        <a href="#" class="fb btn">
          <i class="fa fa-facebook fa-fw"></i> Login with Facebook
         </a>
        <a href="#" class="twitter btn">
          <i class="fa fa-twitter fa-fw"></i> Login with Twitter
        </a>
        <a href="#" class="google btn"><i class="fa fa-google fa-fw">
          </i> Login with Google+
        </a>
      </div>

<div class="col">
        <div class="hide-md-lg">
          <p>Or sign in manually:</p>
        </div>

<div class="bottom-container">
  <div class="row">
    <div class="col">
      <a href="#" style="color:white" class="btn">Sign up</a>
    </div>
    <div class="col">
      <a href="#" style="color:white" class="btn">Forgot password?</a>
    </div>
  </div>
</div>

</body>
</html>