在Bootstrap 4中使用.align-self-start类从头开始对齐flex项目。
要从一开始就对齐弹性项目，您需要在该特定弹性项目中设置类-
<div class="p-2 border align-self-start"> Item 3 </div>
上面是在flex类内部设置的，如下所示-
<div class="d-flex bg-info" style="height:200px"> <div class="p-2 border">Item 1</div> <div class="p-2 border">Item 2</div> <div class="p-2 border align-self-start">Item 3</div> <div class="p-2 border">Item 4</div> </div>
您可以尝试运行以下代码来实现align-self-start类-
<!DOCTYPE html> <html lang="en"> <head> <title>Bootstrap Example</title> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1"> <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.0/css/bootstrap.min.css"> <script src="https://cdn.staticfile.org/jquery/3.3.1/jquery.min.js"></script> <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.0/js/bootstrap.min.js"></script> </head> <body> <div class="container mt-3"> <h1>Align Specific Flex Item from the start</h1> <div class="d-flex bg-info" style="height:200px"> <div class="p-2 border">Item 1</div> <div class="p-2 border">Item 2</div> <div class="p-2 border align-self-start">Item 3</div> <div class="p-2 border">Item 4</div> </div> </div> </body> </html>