我有两行,想在顶部和臀部加上一些空间。因此,我添加了mt-3和mb-3属性。但是,这些属性似乎只应用于第一行。
如何将它们应用于每一行?
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" integrity="sha384-WskhaSGFgHYWDcbwN70/dfYBj47jz9qbsMId/iRN3ewGhXQFZCSftd1LZCfmhktB" crossorigin="anonymous">
</head>
<body>
<div class="row mt-3 mb-3" style="background-color:white">
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
</div>
<div class="row mt-3 mb-3" style="background-color:whitesmoke">
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js" integrity="sha384-ZMP7rVo3mIykV+2+9J3UJ46jBk0WLaUAdn689aCwoqbBJiSnjAK/l8WvCWPIPm49" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js" integrity="sha384-smHYKdLADwkXOn1EmN1qk/HfnUcbVRZyYmZ4qpPea6sjB/pTJ0euyQp0Mk8ck+5T" crossorigin="anonymous"></script>
</body>
</html>发布于 2018-05-20 22:12:43
你所拥有的被称为margin collapse
..。当两个元素的垂直边距接触时,只有具有最大边距值的元素的边距将被授予,而较小边距值的元素的边距将被折叠为零。
从本质上说,边距适用于这两个元素,但边距重叠。
要解决这个问题,您有三个选项:
float: leftposition: absolutedisplay: inline-block最简单的解决方案(在我看来)是简单地将float: left应用于有问题的元素:
.mt-3, .mb-3 {
float: left;
}<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" integrity="sha384-WskhaSGFgHYWDcbwN70/dfYBj47jz9qbsMId/iRN3ewGhXQFZCSftd1LZCfmhktB" crossorigin="anonymous">
<link href="styles.css" rel="stylesheet" />
<title>Web-UI-Automation</title>
</head>
<body>
<div class="row mt-3 mb-3" style="background-color:white">
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
</div>
<div class="row mt-3 mb-3" style="background-color:whitesmoke">
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
<div class="col-3">
completions based on variable types, function definitions, and imported modules.
</div>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js" integrity="sha384-ZMP7rVo3mIykV+2+9J3UJ46jBk0WLaUAdn689aCwoqbBJiSnjAK/l8WvCWPIPm49" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js" integrity="sha384-smHYKdLADwkXOn1EmN1qk/HfnUcbVRZyYmZ4qpPea6sjB/pTJ0euyQp0Mk8ck+5T" crossorigin="anonymous"></script>
</body>
</html>
https://stackoverflow.com/questions/50439840
复制相似问题