There is the solution if you need only outline without border. It's not mine. I got if from Bootstrap css file. If you specify outline: 1px auto certain_color, you'll get thin outer line around div of certain color. In this case the specified width has no matter, even if you specify 10 px width, anyway it will be thin line. The key word in mentioned rule is "auto". If you need outline with rounded corners and certain width, you may add css rule on border with needed width and same color. It makes outline thicker.

结合盒子阴影和轮廓。

李·海耶斯的回答有点小变化 我发现

input[type=text]:focus {
    box-shadow: 0 0 0 1pt red;
    outline-width: 1px;
    outline-color: red;
}

最后的效果非常干净。没有使用边界半径时的大小跳跃

There is the solution if you need only outline without border. It's not mine. I got if from Bootstrap css file. If you specify outline: 1px auto certain_color, you'll get thin outer line around div of certain color. In this case the specified width has no matter, even if you specify 10 px width, anyway it will be thin line. The key word in mentioned rule is "auto". If you need outline with rounded corners and certain width, you may add css rule on border with needed width and same color. It makes outline thicker.

我觉得你在找这样的东西。

div {
    -webkit-border-radius: 10px;
    -moz-border-radius: 10px;
    border-radius: 10px;
    border: 1px solid black;
    background-color: #CCC;
    height: 100px;
    width: 160px;
}

Edit

有一个firefox专用的-moz-outline-radius，但这在IE/Chrome/Safari/Opera等浏览器上行不通。所以，看起来最跨浏览器兼容的方法*是使用包装器div:

div.inner { -webkit-border-radius: 10 px; -moz-border-radius: 10 px; border - radius: 10 px; 边框:1px纯黑色; background - color: # CCC; 身高:100 px; 宽度:160 px; ｝ div.outer { 显示:inline-block; -webkit-border-radius: 10 px; -moz-border-radius: 10 px; border - radius: 10 px; 边框:1px纯红色; ｝ < div class = "外" > < div class = "内部" > < / div > < / div >

*除了使用图像

如果你想要浮雕效果，你可以这样做:

.embossed { background: #e5e5e5; height: 100px; width: 200px; border: #FFFFFF solid 1px; outline: #d0d0d0 solid 1px; margin: 15px; } .border-radius { border-radius: 20px 20px 20px 20px; -webkit-border-radius: 20px; -moz-border-radius: 20px; -khtml-border-radius: 20px; } .outline-radius { -moz-outline-radius: 21px; } <div class="embossed"></div> <div class="embossed border-radius"></div> <div class="embossed border-radius outline-radius">-MOZ ONLY</div>

我还没有找到一个工作周围有这个工作在其他浏览器。

编辑:你能做到这一点的唯一其他方法是使用盒子阴影，但如果你已经在该元素上有一个盒子阴影，这将不起作用。

我把轮廓设置为透明。

input[type=text] {
  outline: rgba(0, 0, 0, 0);
  border-radius: 10px;
}

input[type=text]:focus {    
  border-color: #0079ff;
}