你可以通过两种方式做到这一点
- 使用background(background-image) css 属性。您还可以设置背景大小以帮助调整背景大小(即保持图像包含在父级中,让它溢出,拉伸以适应等)
- 将img 元素的位置css 属性设置为绝对值,将卡片的z-index设置为高于 img 元素的 z-index 的某个值。
不知道 Materialize CSS 是否为其中一些设置提供了预制的 css 类,您必须查看他们的文档。
背景 css 属性
CSS
.cardbg {
background:url(URL) no-repeat 0% 0%;
background-size:cover;
}
HTML
<div class="cardbg">
<div class="card z-depth-5 teal darken-4">
<span class="card-title white-text text-darken-4">
</span>
</div>
</div>
定位的 img 元素
CSS
.container {
position:relative;
}
.card {
position:relative;
z-index:10;
}
.cardbg {
position:absolute;
left:0px;
top:0px;
width:100%;
height:100%;
z-index:1;
}
HTML
<div class="container">
<img src="URL" class="cardbg" />
<div class="card z-depth-5 teal darken-4">
<span class="card-title white-text text-darken-4">
</span>
</div>
</div>
背景 css 演示
.cardbg {
position:absolute;
left:0px;
top:0px;
width:100%;
height:100%;
background:url(http://placehold.it/1024x768) no-repeat 0% 0%;
background-size:cover;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/materialize/0.95.3/js/materialize.min.js"></script>
<link href="https://cdnjs.cloudflare.com/ajax/libs/materialize/0.95.3/css/materialize.min.css" rel="stylesheet" />
<div class="cardbg">
<div class="card z-depth-5 teal darken-4">
<span class="card-title white-text text-darken-4">
Some card
</span>
</div>
</div>
定位元素演示
.container {
position:absolute;
left:0px;
top:0px;
width:100%;
height:100%;
}
.card {
position:relative;
z-index:1;
}
.cardbg {
position:absolute;
left:0px;
top:0px;
width:100%;
height:100%;
z-index:0;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/materialize/0.95.3/js/materialize.min.js"></script>
<link href="https://cdnjs.cloudflare.com/ajax/libs/materialize/0.95.3/css/materialize.min.css" rel="stylesheet" />
<div class="container">
<img src="http://placehold.it/1024x768" class="cardbg" />
<div class="card z-depth-5 teal darken-4">
<span class="card-title white-text text-darken-4">
Some text
</span>
</div>
</div>