按著視頻敲的 為什么三級(jí)菜單的小箭頭不顯示呢
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.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;
}
.top-nav:before,.top-nav:after{
content:" ";
display: table;
}
.top-nav:after{
clear: both;
}
.top-nav{
zoom:1;
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.top-nav li{
float: left;
border-right: 1px solid #222;
box-shadow: 1px 0 0 #444;
position: relative;
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.top-nav li a{
float: left;
padding: 12px 30px;
color: #999;
font: bold 12px;
text-decoration: none;
text-shadow: 0 1px 0 #000;
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.top-nav li a:hover{
color: #fafafa;
}
.top-nav li ul{
visibility: hidden;
position: absolute;
list-style: none;
top: 38px;
left: 0;
z-index: 1;
padding: 0;
background-color: #444;
background-image: linear-gradient(#444,#111);
box-shadow: 0 -1 0 rgba(255,255,255,.3);
border-radius: 3px;
opacity: 0;
margin: 20px 0 0 0;
transition: all .2s ease-in-out;
_margin: 0;
}
.top-nav li:hover > ul{
opacity: 1;
visibility: visible;
margin: 0;
}
.top-nav ul li{
float: none;
display: block;
border: 0;
box-shadow: 0 1px 0 #111,0 2px 0 #666;
}
.top-nav ul a{
padding: 10px;
width: 130px;
display: block;
float: none;
_height: 10px;
}
.top-nav ul a:hover{
background-color: #0186ba;
background-image: linear-gradient(#04acec,#0186ba);
}
.top-nav ul li:first-child > a{
border-radius: 3px 3px 0 0;
}
.top-nav ul li:last-child > a{
border-radius: 0 0 3px 3px;
}
.top-nav ul li:first-child > a:before{
content: "";
position: absolute;
left: 40px;
top: -6px;
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;
}
.top-nav ul ul{
top:0;
left: 150px;
margin:0 0 0 20px;
_margin: 0;
box-shadow: -1px 0 0 rgba(255,255,255,.3);
}
.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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$(this).children('ul').css('visibility','visible');
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$(this).children('ul').css('visibility','hidden');
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2018-09-19
.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;
}
加黑部分多了一個(gè)冒號(hào)。