Hi estherft,
You can create the custom module with the following HTML code:
<ul class="cto-item-left-side">
<li><a href="#">item 1</a></li>
<li><a href="#">item 2</a></li>
<li><a href="#">item 3</a></li>
<li><a href="#">item 4</a></li>
<li><a href="#">item 5</a></li>
<li><a href="#">item 6</a></li>
</ul>
Then create the templates/cassiopeia/css/user.css file and add the following code to the file.
ul.cto-item-left-side {
list-style-type: none;
margin: 0;
padding: 0;
}
ul.cto-item-left-side li {
background: orange;
margin-bottom: 10px;
border-radius: 10px;
}
ul.cto-item-left-side li a {
display: block;
color: #fff;
padding: 3px 20px;
}
Hope this helps!