我正在尝试在活动菜单项上添加箭头，我已经使箭头工作但我无法设置箭头的背景。
请参阅下面的演示链接。
演示链接： https://jsfiddle.net/afjrhLwq/
CSS
.navbar-default {
background: #fff;;
border-bottom: 0;
font-size: 1em;
padding-top: 20px;
}
.navbar-default .navbar-nav {
font-weight: bold;
}
.navbar-default .navbar-nav > .active {
color: #000;
}
.navbar-default .navbar-nav > .active > a,
.navbar-default .navbar-nav > .active > a:hover,
.navbar-default .navbar-nav > .active > a:focus {
color: #000;
background: transparent;
}
.navbar-nav > li.active:before,
.navbar-nav > li.active:after {
content: "";
bottom: -14px;
position: absolute;
border-top: 13px solid #fff;
border-bottom: 3px solid #00b4f0;
margin: 0 8px;
left: 50%;
width: 9999px;
}
.navbar-nav > li.active:after {
left: auto;
right: 50%;
}
.navbar-nav > li.active a:after {
content: "";
width: 13px;
height: 14px;
position: absolute;
top: solid #00b4f0;
border: solid #00b4f0;
border-width: 3px 3px 0 0;
top: 100%;
left: 0;
right: 0;
margin: 5px auto 0;
-moz-transform: rotate(310deg);
-webkit-transform: rotate(310deg);
-ms-transform: rotate(310deg);
}
感谢您寻找：）
答案 0 :(得分：0)
我已经改变了我的解决方案
现在箭头非常透明。我已经纠正了一些属性，并在解决方案中添加了两个白角：
.navbar-nav > li.active a:before {
content: "";
position: absolute;
top: 100%;
left: 0;
right: 0;
width: 0;
height: 0;
margin: 0 auto;
border-left: 9px solid white;
border-right: 9px solid white;
border-bottom: 11px solid transparent;
}
在此代码中，箭头有一个透明的三角形：
@import url('https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css');
.navbar-brand {
font-size: 1.7em;
color: #000;
}
.navbar-brand span {
color: #00b4f0;
font-weight: bold;
}
.navbar-default {
background: #fff;
border-bottom: 0;
font-size: 1em;
padding-top: 20px;
}
.navbar-default .navbar-nav {
font-weight: bold;
}
.navbar-default .navbar-nav > .active {
color: #000;
}
.navbar-default .navbar-nav > .active > a,
.navbar-default .navbar-nav > .active > a:hover,
.navbar-default .navbar-nav > .active > a:focus {
color: #000;
background: transparent;
}
.navbar-nav > li.active:before,
.navbar-nav > li.active:after {
content: "";
bottom: -13px;
position: absolute;
border-top: 11px solid #fff;
border-bottom: 3px solid #00b4f0;
margin: 0 9px;
left: 50%;
width: 9999px;
}
.navbar-nav > li.active:after {
left: auto;
right: 50%;
}
.navbar-nav > li.active a:before,
.navbar-nav > li.active a:after {
content: "";
position: absolute;
top: 100%;
left: 0;
right: 0;
}
.navbar-nav > li.active a:before { /* Two white triangles. */
width: 0;
height: 0;
margin: 0 auto;
border-left: 9px solid white;
border-right: 9px solid white;
border-bottom: 11px solid transparent;
}
.navbar-nav > li.active a:after { /* Two blue borders. */
width: 14px; /* Now the width is equal to the height. */
height: 14px;
margin: 4px auto 0;
border: solid #00b4f0;
border-width: 3px 3px 0 0;
-webkit-transform: rotate(315deg); /* 315 instead of 310 */
-moz-transform: rotate(315deg);
-ms-transform: rotate(315deg);
transform: rotate(315deg);
}
.jumbotron {
margin-top: 36px;
}<!-- Fixed navbar -->
<div class="page-body">
<nav class="navbar navbar-default navbar-fixed-top">
<div class="container">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#"><span>dashboard</span></a>
</div>
<div id="navbar" class="collapse navbar-collapse">
<ul class="nav navbar-nav">
<li class="active"><a href="#">Home</a>
</li>
<li><a href="#about">About</a>
</li>
<li><a href="#contact">Contact</a>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Dropdown <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="#">Action</a>
</li>
<li><a href="#">Another action</a>
</li>
<li><a href="#">Something else here</a>
</li>
<li role="separator" class="divider"></li>
<li class="dropdown-header">Nav header</li>
<li><a href="#">Separated link</a>
</li>
<li><a href="#">One more separated link</a>
</li>
</ul>
</li>
</ul>
</div>
<!--/.nav-collapse -->
</div>
</nav>
<!-- Main jumbotron for a primary marketing message or call to action -->
<div class="jumbotron bluebg">
<div class="container">
<h1>Hello, world!</h1>
<p>This is a template for a simple marketing or informational website. It includes a large callout called a jumbotron and three supporting pieces of content. Use it as a starting point to create something more unique.</p>
<p>This is a template for a simple marketing or informational website. It includes a large callout called a jumbotron and three supporting pieces of content. Use it as a starting point to create something more unique.</p>
<p>This is a template for a simple marketing or informational website. It includes a large callout called a jumbotron and three supporting pieces of content. Use it as a starting point to create something more unique.</p>
<p><a class="btn btn-primary btn-lg" href="#" role="button">Learn more »</a>
</p>
</div>
</div>
<!-- Begin page content -->
<div class="container">
<div class="page-header">
<h1>Sticky footer with fixed navbar</h1>
</div>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
</div>
<footer class="footer">
<div class="container">
<p class="text-muted">Place sticky footer content here.</p>
</div>
</footer>
https://jsfiddle.net/glebkema/jwn695s9/
之前的版本有一个灰色的不透明三角形
我用过
.navbar {
border-bottom: 3px solid #00b4f0;
}
而不是
.navbar-nav > li.active:before,
.navbar-nav > li.active:after {
content: "";
bottom: -14px;
position: absolute;
border-top: 13px solid #fff;
border-bottom: 3px solid #00b4f0;
margin: 0 8px;
left: 50%;
width: 9999px;
}
.navbar-nav > li.active:after {
left: auto;
right: 50%;
}
我用过
.navbar-nav > li.active a:after {
width: 14px;
height: 14px;
margin: -6px auto 0;
-moz-transform: rotate(315deg); /* 315 instead of 310 */
-webkit-transform: rotate(315deg);
-ms-transform: rotate(315deg);
background: linear-gradient(225deg, #eee 0%, #eee 55%, rgba(0, 0, 0, 0) 55%, rgba(0, 0, 0, 0) 100%);
/* #eee = background-color of .jumbotron */
}
而不是
.navbar-nav > li.active a:after {
width: 13px;
height: 14px;
margin: 5px auto 0;
-moz-transform: rotate(310deg);
-webkit-transform: rotate(310deg);
-ms-transform: rotate(310deg);
}
在此代码中，箭头有一个灰色的不透明三角形：
@import url('https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css');
.navbar-brand {
font-size: 1.7em;
color: #000;
}
.navbar-brand span {
color: #00b4f0;
font-weight: bold;
}
.navbar-default {
background: #fff;
border-bottom: 0;
font-size: 1em;
padding-top: 20px;
}
.navbar-default .navbar-nav {
font-weight: bold;
}
.navbar-default .navbar-nav > .active {
color: #000;
}
.navbar-default .navbar-nav > .active > a,
.navbar-default .navbar-nav > .active > a:hover,
.navbar-default .navbar-nav > .active > a:focus {
color: #000;
background: transparent;
}
.navbar {
border-bottom: 3px solid #00b4f0;
}
.navbar-nav > li.active a:after {
content: "";
width: 14px;
height: 14px;
position: absolute;
top: solid #00b4f0;
border: solid #00b4f0;
border-width: 3px 3px 0 0;
top: 100%;
left: 0;
right: 0;
margin: -6px auto 0;
-moz-transform: rotate(315deg); /* 315 instead of 310 */
-webkit-transform: rotate(315deg);
-ms-transform: rotate(315deg);
background: linear-gradient(225deg, #eee 0%, #eee 55%, rgba(0, 0, 0, 0) 55%, rgba(0, 0, 0, 0) 100%);
/* #eee = background-color of .jumbotron */
}<!-- Fixed navbar -->
<div class="page-body">
<nav class="navbar navbar-default navbar-fixed-top">
<div class="container">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand" href="#"><span>dashboard</span></a>
</div>
<div id="navbar" class="collapse navbar-collapse">
<ul class="nav navbar-nav">
<li class="active"><a href="#">Home</a>
</li>
<li><a href="#about">About</a>
</li>
<li><a href="#contact">Contact</a>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Dropdown <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="#">Action</a>
</li>
<li><a href="#">Another action</a>
</li>
<li><a href="#">Something else here</a>
</li>
<li role="separator" class="divider"></li>
<li class="dropdown-header">Nav header</li>
<li><a href="#">Separated link</a>
</li>
<li><a href="#">One more separated link</a>
</li>
</ul>
</li>
</ul>
</div>
<!--/.nav-collapse -->
</div>
</nav>
<!-- Main jumbotron for a primary marketing message or call to action -->
<div class="jumbotron bluebg">
<div class="container">
<h1>Hello, world!</h1>
<p>This is a template for a simple marketing or informational website. It includes a large callout called a jumbotron and three supporting pieces of content. Use it as a starting point to create something more unique.</p>
<p>This is a template for a simple marketing or informational website. It includes a large callout called a jumbotron and three supporting pieces of content. Use it as a starting point to create something more unique.</p>
<p>This is a template for a simple marketing or informational website. It includes a large callout called a jumbotron and three supporting pieces of content. Use it as a starting point to create something more unique.</p>
<p><a class="btn btn-primary btn-lg" href="#" role="button">Learn more »</a>
</p>
</div>
</div>
<!-- Begin page content -->
<div class="container">
<div class="page-header">
<h1>Sticky footer with fixed navbar</h1>
</div>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
<p class="lead">Pin a fixed-height footer to the bottom of the viewport in desktop browsers with this custom HTML and CSS. A fixed navbar has been added with <code>padding-top: 60px;</code> on the <code>body > .container</code>.</p>
<p>Back to <a href="../sticky-footer">the default sticky footer</a> minus the navbar.</p>
</div>
<footer class="footer">
<div class="container">
<p class="text-muted">Place sticky footer content here.</p>
</div>
</footer>