link hover change parent element style

So I have an unordered list, with list items containing hyperlink tags

<ul>
 <li> 
  <a href="#">Tag</a>
 </li>
<ul>

On my LI tag, I have a border bottom set to the background color.

When my link is hovered I want to change the color of it?

How do I change the previous elements style?

ul li a:hover{
 text-decoration: none;
 color: #Blue;
}
 
ul li a:hover li{
 border-bottom: solid 5px #Green;
}