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按着视频敲的 为什么三级菜单的小箭头不显示呢

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<style type="text/css">

.top-nav{

width: 960px;

margin: 60px auto;

border: 1px solid #222;

background-color: #111;

background-image: linear-gradient(#444,#111);

border-radius: 6px;

box-shadow: 0 1px 1px #777;

padding: 0;

list-style: none;

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.top-nav:before,.top-nav:after{

content:" ";

display: table;

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clear: both;

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zoom:1;

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float: left;

border-right: 1px solid #222;

box-shadow: 1px 0 0 #444;

position: relative;

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padding: 12px 30px;

color: #999;

font: bold 12px;

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float: none;

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border: 0;

box-shadow: 0 1px 0 #111,0 2px 0 #666;

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padding: 10px;

width: 130px;

display: block;

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background-image: linear-gradient(#04acec,#0186ba);

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border-left: 6px solid transparent;

border-right: 6px solid transparent;

border-bottom: 6px solid #444;

}

.top-nav ul li:first-child > a:hover:before{

border-bottom-color: #04acec;

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left: 150px;

margin:0 0 0 20px;

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box-shadow: -1px 0 0 rgba(255,255,255,.3);

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.top-nav ul ul li:first-child a:before{

left: :-6px;

top: 50%;

margin-top: -6px;

border-left: 0;

border-bottom: 6px solid transparent;

border-top: 6px solid transparent;

border-right: 6px solid #3b3b3b;

}

.top-nav ul ul li:first-child a:hover:before{

border-right-color: #0299d3;

border-bottom-color: transparent;

}

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1 回答

.top-nav ul ul li:first-child a:before{

left: :-6px;

top: 50%;

margin-top: -6px;

border-left: 0;

border-bottom: 6px solid transparent;

border-top: 6px solid transparent;

border-right: 6px solid #3b3b3b;

}

加黑部分多了一个冒号。


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按着视频敲的 为什么三级菜单的小箭头不显示呢

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