css3渐变画斜线 demo

效果图：

代码：

<div class = 'demo1'></div>
<style>
    .demo1{
       width: 300px;
       height: 120px;
       border: 1px solid #000;
       background: linear-gradient(to left top, transparent 49.5%, red, transparent 50.5%);//调节百分比，间接设置斜线的宽度，位置，斜线方向 由左向上
    }
</style>

效果图:

代码：

<div class='demo2'></div>
<style>
     .demo2{
        width:300px;
        height:120px;
        border: 1px solid #000;
        background: linear-gradient(to top right, transparent 49.5%, red, transparent 50.5%);//调节百分比，简介设置斜线的宽度，位置，斜线方向由上向右
}
</style>

为更好的了解百分比的设置，现将.demo1的background稍作修改

 background: linear-gradient(to left top, transparent 20%, red, transparent 100%);

background: linear-gradient(to left top, transparent 20%, red, transparent 51%);

.demo2的background稍作修改

background: linear-gradient(to top right, transparent 20%, red, transparent 100%);

    background: linear-gradient(to top right, transparent 20%, red, transparent 51%);