<!----------------------首页可灵活切换大型板块开始了----------------------->
<nav>
<div class="nav nav-tabs" id="nav-tab" role="tablist">
<a class="nav-link active" data-toggle="tab" href="#nav-111" role="tab" aria-selected="false"><i class="fas fa-tshirt"></i>  AAA</a>
<a class="nav-link" data-toggle="tab" href="#nav-222" role="tab" aria-selected="true"><i class="fas fa-user-astronaut"></i>  BBB</a>
<a class="nav-link" data-toggle="tab" href="#nav-333" role="tab" aria-selected="false"><i class="fas fa-cat-space"></i>  CCC</a>
<a class="nav-link" data-toggle="tab" href="#nav-444" role="tab" aria-selected="false"><i class="fas fa-skull"></i>  DDD</a>
</div>
</nav>

<div class="tab-content" id="nav-tabContent">
<div class="tab-pane fade show active" id="nav-111" role="tabpanel" aria-labelledby="nav-home-tab">
<br>
<div class="media">
<div class="media-body">
<!------------- 1 / 4 ---------------->
<span style="font-size:50px; font-weight: bold;">AAA</span >
<!------------- 1 / 4 ---------------->
</div>
</div>
</div>

<div class="tab-pane fade" id="nav-222" role="tabpanel" aria-labelledby="nav-profile-tab">
<br>
<div class="media">
<div class="media-body">
<!------------- 2 / 4 ---------------->
<span style="font-size:50px; font-weight: bold;">BBB</span >
<!------------- 2 / 4 ---------------->
</div>
</div>
</div>

<div class="tab-pane fade" id="nav-333" role="tabpanel" aria-labelledby="nav-profile-tab">
<br>
<div class="media">
<div class="media-body">
<!------------- 3 / 4 ---------------->
<span style="font-size:50px; font-weight: bold;">CCC</span >
<!------------- 3 / 4 ---------------->
</div>
</div>
</div>

<div class="tab-pane fade" id="nav-444" role="tabpanel" aria-labelledby="nav-profile-tab">
<br>
<div class="media">
<div class="media-body">
<!------------- 4 / 4 ---------------->
<span style="font-size:50px; font-weight: bold;">DDD</span >
<!------------- 4 / 4 ---------------->
</div>
</div>
</div>

</div>
<!----------------------首页可灵活切换大型板块结束了----------------------->

<!-------------被选中标签颜色切换---------------->
<style>
.nav-link {
  color: #9B9B9B !important;
}
.nav-link.active {
  color: #000000 !important; 
}
</style>
<!-------------被选中标签颜色切换---------------->