本文共 1410 字，大约阅读时间需要 4 分钟。
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<!DOCTYPE html>
<html>
<head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1"> <meta name="description" content=""> <meta name="author" content=""> <link rel="icon" href="../../favicon.ico"><title>Signin Template for Bootstrap</title>
<!-- Bootstrap core CSS -->
<link href=" rel="stylesheet"> <style> .vertical-center { position: absolute; top: 40%; left: 50%; transform: translate(-50%, -50%); } </style></head><body> <div class="container vertical-center" style="border:1px solid blue;"> <div class="col-lg-4 col-lg-offset-4 col-sm-6 col-sm-offset-3 col-xs-8 col-xs-offset-2" id="logindev" style="border:1px solid red;"> <form class="form"> <h2>Please sign in</h2> <label for="inputEmail" class="sr-only">Email address</label> <input type="email" id="inputEmail" class="form-control" placeholder="Email address" required="" autofocus=""> <label for="inputPassword" class="sr-only">Password</label> <input type="password" id="inputPassword" class="form-control" placeholder="Password" required=""> <div class="checkbox"> <label> <input type="checkbox" value="remember-me"> Remember me </label> </div> <button class="btn btn-lg btn-primary btn-block" type="submit">Sign in</button> </form> </div> </div> <!-- /container --></body></html>