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<!DOCTYPE html> <html> <head> <title>Bootstrap 实例</title> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1"> <link rel="stylesheet" href="https://cdn.staticfile.org/twitter-bootstrap/4.3.1/css/bootstrap.min.css"> <script src="https://cdn.staticfile.org/jquery/3.2.1/jquery.min.js"></script> <script src="https://cdn.staticfile.org/popper.js/1.15.0/umd/popper.min.js"></script> <script src="https://cdn.staticfile.org/twitter-bootstrap/4.3.1/js/bootstrap.min.js"></script> </head> <body> <div class="container mt-3"> <h2>居中位置</h2> <p>.align-content-*-center classes 根据不同屏幕设备在中间位置堆叠元素。</p> <p><code>.align-content-center</code>:</p> <div class="d-flex flex-wrap align-content-center bg-light" style="height:300px"> <div class="p-2 border">Flex item 1</div> <div class="p-2 border">Flex item 2</div> <div class="p-2 border">Flex item 3</div> <div class="p-2 border">Flex item 4</div> <div class="p-2 border">Flex item 5</div> <div class="p-2 border">Flex item 6</div> <div class="p-2 border">Flex item 7</div> <div class="p-2 border">Flex item 8</div> <div class="p-2 border">Flex item 9</div> <div class="p-2 border">Flex item 10</div> <div class="p-2 border">Flex item 11</div> <div class="p-2 border">Flex item 12</div> <div class="p-2 border">Flex item 13 </div> <div class="p-2 border">Flex item 14</div> <div class="p-2 border">Flex item 15</div> <div class="p-2 border">Flex item 16</div> <div class="p-2 border">Flex item 17</div> <div class="p-2 border">Flex item 18</div> <div class="p-2 border">Flex item 19</div> <div class="p-2 border">Flex item 20</div> <div class="p-2 border">Flex item 21</div> <div class="p-2 border">Flex item 22</div> <div class="p-2 border">Flex item 23</div> <div class="p-2 border">Flex item 24</div> <div class="p-2 border">Flex item 25</div> </div> <br> <p><code>.align-content-sm-center</code>:</p> <div class="d-flex flex-wrap align-content-sm-center bg-light" style="height:300px"> <div class="p-2 border">Flex item 1</div> <div class="p-2 border">Flex item 2</div> <div class="p-2 border">Flex item 3</div> <div class="p-2 border">Flex item 4</div> <div class="p-2 border">Flex item 5</div> <div class="p-2 border">Flex item 6</div> <div class="p-2 border">Flex item 7</div> <div class="p-2 border">Flex item 8</div> <div class="p-2 border">Flex item 9</div> <div class="p-2 border">Flex item 10</div> <div class="p-2 border">Flex item 11</div> <div class="p-2 border">Flex item 12</div> <div class="p-2 border">Flex item 13 </div> <div class="p-2 border">Flex item 14</div> <div class="p-2 border">Flex item 15</div> <div class="p-2 border">Flex item 16</div> <div class="p-2 border">Flex item 17</div> <div class="p-2 border">Flex item 18</div> <div class="p-2 border">Flex item 19</div> <div class="p-2 border">Flex item 20</div> <div class="p-2 border">Flex item 21</div> <div class="p-2 border">Flex item 22</div> <div class="p-2 border">Flex item 23</div> <div class="p-2 border">Flex item 24</div> <div class="p-2 border">Flex item 25</div> </div> <br> <p><code>.align-content-md-center</code>:</p> <div class="d-flex flex-wrap align-content-md-center bg-light" style="height:300px"> <div class="p-2 border">Flex item 1</div> <div class="p-2 border">Flex item 2</div> <div class="p-2 border">Flex item 3</div> <div class="p-2 border">Flex item 4</div> <div class="p-2 border">Flex item 5</div> <div class="p-2 border">Flex item 6</div> <div class="p-2 border">Flex item 7</div> <div class="p-2 border">Flex item 8</div> <div class="p-2 border">Flex item 9</div> <div class="p-2 border">Flex item 10</div> <div class="p-2 border">Flex item 11</div> <div class="p-2 border">Flex item 12</div> <div class="p-2 border">Flex item 13 </div> <div class="p-2 border">Flex item 14</div> <div class="p-2 border">Flex item 15</div> <div class="p-2 border">Flex item 16</div> <div class="p-2 border">Flex item 17</div> <div class="p-2 border">Flex item 18</div> <div class="p-2 border">Flex item 19</div> <div class="p-2 border">Flex item 20</div> <div class="p-2 border">Flex item 21</div> <div class="p-2 border">Flex item 22</div> <div class="p-2 border">Flex item 23</div> <div class="p-2 border">Flex item 24</div> <div class="p-2 border">Flex item 25</div> </div> <br> <p><code>.align-content-lg-center</code>:</p> <div class="d-flex flex-wrap align-content-lg-center bg-light" style="height:300px"> <div class="p-2 border">Flex item 1</div> <div class="p-2 border">Flex item 2</div> <div class="p-2 border">Flex item 3</div> <div class="p-2 border">Flex item 4</div> <div class="p-2 border">Flex item 5</div> <div class="p-2 border">Flex item 6</div> <div class="p-2 border">Flex item 7</div> <div class="p-2 border">Flex item 8</div> <div class="p-2 border">Flex item 9</div> <div class="p-2 border">Flex item 10</div> <div class="p-2 border">Flex item 11</div> <div class="p-2 border">Flex item 12</div> <div class="p-2 border">Flex item 13 </div> <div class="p-2 border">Flex item 14</div> <div class="p-2 border">Flex item 15</div> <div class="p-2 border">Flex item 16</div> <div class="p-2 border">Flex item 17</div> <div class="p-2 border">Flex item 18</div> <div class="p-2 border">Flex item 19</div> <div class="p-2 border">Flex item 20</div> <div class="p-2 border">Flex item 21</div> <div class="p-2 border">Flex item 22</div> <div class="p-2 border">Flex item 23</div> <div class="p-2 border">Flex item 24</div> <div class="p-2 border">Flex item 25</div> </div> <br> <p><code>.align-content-xl-center</code>:</p> <div class="d-flex flex-wrap align-content-xl-center bg-light" style="height:300px"> <div class="p-2 border">Flex item 1</div> <div class="p-2 border">Flex item 2</div> <div class="p-2 border">Flex item 3</div> <div class="p-2 border">Flex item 4</div> <div class="p-2 border">Flex item 5</div> <div class="p-2 border">Flex item 6</div> <div class="p-2 border">Flex item 7</div> <div class="p-2 border">Flex item 8</div> <div class="p-2 border">Flex item 9</div> <div class="p-2 border">Flex item 10</div> <div class="p-2 border">Flex item 11</div> <div class="p-2 border">Flex item 12</div> <div class="p-2 border">Flex item 13 </div> <div class="p-2 border">Flex item 14</div> <div class="p-2 border">Flex item 15</div> <div class="p-2 border">Flex item 16</div> <div class="p-2 border">Flex item 17</div> <div class="p-2 border">Flex item 18</div> <div class="p-2 border">Flex item 19</div> <div class="p-2 border">Flex item 20</div> <div class="p-2 border">Flex item 21</div> <div class="p-2 border">Flex item 22</div> <div class="p-2 border">Flex item 23</div> <div class="p-2 border">Flex item 24</div> <div class="p-2 border">Flex item 25</div> </div> </div> </body> </html>
运行结果