废话不多说了，直接大家贴代码了，具体代码如下所示；
*{
margin: 0;
padding: 0;
}
ul,li{
list-style: none;
}
.ui-slide-box{
width: 300px;
}
.ui-slide-item{
width: 100%;
position: relative;
}
.ui-slide-item-text{
display: block;
background-color: #000000;
color: white;
border-bottom: 1px solid yellow;
height: 40px;
line-height: 40px;
}
.ui-slide-item .ui-slide-box{
display: none;
position: absolute;
left: 300px;
top: 0;
}
.ui-slide-item:hover > .ui-slide-box{
display: block;
}
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">aaaaaaaaaaaaa</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">aaaaaaaaaaaa</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">dddddddd </span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">sssssssssssss</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">eeeeeeeeeeee</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">ccccccccccccc</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">aaaaaaaaaaaaa</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">aaaaaaaaaaaa</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">dddddddd </span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">sssssssssssss</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">eeeeeeeeeeee</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">ccccccccccccc</span>
</li>
</ul>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">bbbbbbbbbb</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">sfsdfsdfsd </span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">cvwdfsd</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">ewewewe</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">xxcxc</span>
</li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">bbbbbbbbbb</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">sfsdfsdfsd </span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">cvwdfsd</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">ewewewe</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">xxcxc</span>
</li>
</ul>
</li>
</ul>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">bbbbbbbbbbb</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">aaaaaaaaaaaa</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">dddddddd </span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">sssssssssssss</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">eeeeeeeeeeee</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">ccccccccccccc</span>
</li>
</ul>
</li>
</ul>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">cccccccccccccccccc</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">rrrrrrrrrrrrrrrrrrrrrrrrrr</span>
<ul class="ui-slide-box">
<li class="ui-slide-item">
<span class="ui-slide-item-text">dddddddd </span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">sssssssssssss</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">eeeeeeeeeeee</span>
</li>
<li class="ui-slide-item">
<span class="ui-slide-item-text">ccccccccccccc</span>
</li>
</ul>
</li>
</ul>
</li>
</ul>
总结
以上所述是小编给大家介绍的CSS实现鼠标悬浮无限向下级展示的实例代码，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对网站的支持！