Can anyone help me solve this?
Follow the code:
.aside-menu {
z-index: 1000;
position: fixed;
height: 100%;
top: 40px;
bottom: 0px;
left: 0px;
width: 35px;
background: #F1F1F1;
}
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul ul {
list-style: none;
margin: 0;
padding: 0;
}
#cssmenu ul li.hover,
#cssmenu ul li:hover {
position: relative;
cursor: default;
}
#cssmenu a {
background-color: #F1F1F1;
color: #484848;
display: block;
text-decoration: none;
padding-top: 15px;
padding-left: 10px;
}
#cssmenu ul {
border-right: 2px solid #0fa1e0;
list-style: none;
}
#cssmenu > ul > li:hover:after {
content: '';
display: block;
width: 0;
height: 0;
position: absolute;
right: 0;
top: 50%;
border-top: 10px solid transparent;
border-bottom: 10px solid transparent;
border-right: 10px solid #0fa1e0;
margin-top: -4px;
}
#cssmenu .has-sub:hover > ul {
display: block;
}
#cssmenu .has-sub ul {
display: none;
position: absolute;
width: 150px;
top: 5px;
left: 100%;
}
#cssmenu .has-sub ul li a {
background: #0fa1e0;
filter: none;
display: block;
line-height: 120%;
padding: 10px;
color: #ffffff;
}
#cssmenu .has-sub ul li:hover a {
background: #0c82b5;
}
#cssmenu .has-sub .has-sub:hover > ul {
display: block;
}
#cssmenu .has-sub .has-sub ul {
display: none;
position: absolute;
left: 100%;
top: 0;
}
#cssmenu .has-sub .has-sub ul li a:hover {
background: #09638a;
}
<div class="aside-menu font-1">
<div id='cssmenu'>
<ul>
<li class='active has-sub'><a href='#'><span>b</span></a>
<ul>
<li class='has-sub'><a href='#'><span>Product 1</span></a>
<ul>
<li><a href='#'><span>Sub Product</span></a></li>
<li class='last'><a href='#'><span>Sub Product</span></a></li>
</ul>
</li>
<li class='has-sub'><a href='#'><span>Product 2</span></a></li>
</ul>
</li>
</ul>
</div>
</div>