在折叠菜单中使用双箭头

Question

我想在折叠菜单中使用双箭头（在左侧和右侧），但我不能。

你可以在这里找到一个崩溃的菜单例如：http://bootsnipp.com/snippets/b47p2

我想https://sedo.com/us/的‘工作原理’部分的例子。

我试图解决sedo的代码，但我无法合并。据我所知，他们使用

_transform: rotate(135deg);_ 

使双箭头。

的代码要改变：

HTML：

<div class="container"> 
    <div class="row"> 
     <div class="col-md-8" id="main"> 
      <h3>Doesn't it look better ?</h3> 
      <div class="panel-group" id="accordion" role="tablist" aria-multiselectable="true"> 
       <div class="panel panel-default"> 
       <div class="panel-heading" role="tab" id="headingOne"> 
        <h4 class="panel-title"> 
        <a role="button" data-toggle="collapse" data-parent="#accordion" href="#collapseOne" aria-expanded="true" aria-controls="collapseOne"> 
         Why is it better 
        </a> 
        </h4> 
       </div> 
       <div id="collapseOne" class="panel-collapse collapse in" role="tabpanel" aria-labelledby="headingOne"> 
        <div class="panel-body"> 
        <ul> 
         <li>The titles are block, so you don't have to click the text part to activate it</li> 
         <li>Indicators for expand/collapsing items</li> 
         <li>Removed title links' obnoxious :hover underlinings, and outlines.</li> 
        </ul> 
       </div> 
       </div> 
       </div> 
       <div class="panel panel-default"> 
       <div class="panel-heading" role="tab" id="headingTwo"> 
        <h4 class="panel-title"> 
        <a class="collapsed" role="button" data-toggle="collapse" data-parent="#accordion" href="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo"> 
         Collapsible Group Item #2 
        </a> 
        </h4> 
       </div> 
       <div id="collapseTwo" class="panel-collapse collapse" role="tabpanel" aria-labelledby="headingTwo"> 
        <div class="panel-body"> 
        Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS. 
        </div> 
       </div> 
       </div> 
       <div class="panel panel-default"> 
       <div class="panel-heading" role="tab" id="headingThree"> 
        <h4 class="panel-title"> 
        <a class="collapsed" role="button" data-toggle="collapse" data-parent="#accordion" href="#collapseThree" aria-expanded="false" aria-controls="collapseThree"> 
         Collapsible Group Item #3 
        </a> 
        </h4> 
       </div> 
       <div id="collapseThree" class="panel-collapse collapse" role="tabpanel" aria-labelledby="headingThree"> 
        <div class="panel-body"> 
        Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS. 
        </div> 
       </div> 
       </div> 
      </div> 

      <hr /> 

      <h3>Compared to default</h3> 

      <div class="panel-group" id="accordion_reg" role="tablist" aria-multiselectable="true"> 
       <div class="panel panel-default"> 
       <div class="panel-heading" role="tab" id="headingOne_reg"> 
        <h4 class="panel-title"> 
        <a role="button" data-toggle="collapse" data-parent="#accordion_reg" href="#collapseOne_reg" aria-expanded="true" aria-controls="collapseOne_reg"> 
        Collapsible Group Item #1 
        </a> 
        </h4> 
       </div> 
       <div id="collapseOne_reg" class="panel-collapse collapse in" role="tabpanel" aria-labelledby="headingOne_reg"> 
        <div class="panel-body"> 
        Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS. 
        </div> 
       </div> 
       </div> 
       <div class="panel panel-default"> 
       <div class="panel-heading" role="tab" id="headingTwo_reg"> 
        <h4 class="panel-title"> 
        <a class="collapsed" role="button" data-toggle="collapse" data-parent="#accordion_reg" href="#collapseTwo_reg" aria-expanded="false" aria-controls="collapseTwo_reg"> 
         Collapsible Group Item #2 
        </a> 
        </h4> 
       </div> 
       <div id="collapseTwo_reg" class="panel-collapse collapse" role="tabpanel" aria-labelledby="headingTwo_reg"> 
        <div class="panel-body"> 
        Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS. 
        </div> 
       </div> 
       </div> 
       <div class="panel panel-default"> 
       <div class="panel-heading" role="tab" id="headingThree_reg"> 
        <h4 class="panel-title"> 
        <a class="collapsed" role="button" data-toggle="collapse" data-parent="#accordion_reg" href="#collapseThree_reg" aria-expanded="false" aria-controls="collapseThree_reg"> 
         Collapsible Group Item #3 
        </a> 
        </h4> 
       </div> 
       <div id="collapseThree_reg" class="panel-collapse collapse" role="tabpanel" aria-labelledby="headingThree_reg"> 
        <div class="panel-body"> 
        Anim pariatur cliche reprehenderit, enim eiusmod high life accusamus terry richardson ad squid. 3 wolf moon officia aute, non cupidatat skateboard dolor brunch. Food truck quinoa nesciunt laborum eiusmod. Brunch 3 wolf moon tempor, sunt aliqua put a bird on it squid single-origin coffee nulla assumenda shoreditch et. Nihil anim keffiyeh helvetica, craft beer labore wes anderson cred nesciunt sapiente ea proident. Ad vegan excepteur butcher vice lomo. Leggings occaecat craft beer farm-to-table, raw denim aesthetic synth nesciunt you probably haven't heard of them accusamus labore sustainable VHS. 
        </div> 
       </div> 
       </div> 
      </div> 
     </div> 
     <div class="sidebar col-md-4" id="sideright"> 
      <h3>Sidebar</h3> 
      <p class="well">Some sidebar content</p> 
     </div> 
    </div> 
<div> 

CSS：

#accordion .panel-heading { padding: 0;} 
#accordion .panel-title > a { 
    display: block; 
    padding: 0.4em 0.6em; 
    outline: none; 
    font-weight:bold; 
    text-decoration: none; 
} 

#accordion .panel-title > a.accordion-toggle::before, #accordion a[data-toggle="collapse"]::before { 
    content:"\e113"; 
    float: left; 
    font-family: 'Glyphicons Halflings'; 
    margin-right :1em; 
} 
#accordion .panel-title > a.accordion-toggle.collapsed::before, #accordion a.collapsed[data-toggle="collapse"]::before { 
    content:"\e114"; 
} 

非常感谢你..

Answer 1

改变你的CSS下一

#accordion .panel-heading { 
    padding: 0; 
    position: relative; 
} 
#accordion .panel-title > a { 
    display: block; 
    padding: 0.4em 2em; 
    outline: none; 
    font-weight:bold; 
    text-decoration: none; 
} 

#accordion .panel-title > a.accordion-toggle::before, #accordion a[data-toggle="collapse"]::before, 
#accordion .panel-title > a.accordion-toggle::after, #accordion a[data-toggle="collapse"]::after{ 
    content:"\e113"; 
    position: absolute; 
    font-family: 'Glyphicons Halflings'; 
    top: 0.5em; 

} 
#accordion .panel-title > a.accordion-toggle.collapsed::before, #accordion a.collapsed[data-toggle="collapse"]::before, 
#accordion .panel-title > a.accordion-toggle.collapsed::after, #accordion a.collapsed[data-toggle="collapse"]::after{ 
    content:"\e114"; 
} 
#accordion .panel-title > a.accordion-toggle::before, #accordion a[data-toggle="collapse"]::before, 
#accordion .panel-title > a.accordion-toggle.collapsed::before, #accordion a.collapsed[data-toggle="collapse"]::before { 
    left: 0.5em; 
} 
#accordion .panel-title > a.accordion-toggle.collapsed::after, #accordion a.collapsed[data-toggle="collapse"]::after, 
#accordion .panel-title > a.accordion-toggle::after, #accordion a[data-toggle="collapse"]::after{ 
    right: 0.5em; 
}