Hi there,
try this CSS:
.widget ul {
list-style: none !important;
position: relative;
margin-left: 0 !important;
}
.widget ul li {
padding-left: 2em;
padding-top: 1em;
padding-bottom: 1em;
border-bottom: 1px dashed #4f5a5e;
}
.widget ul li:before {
content: "\2756";
position: absolute;
top: 1em;
left: 0;
font-size: 22px;
color: #4f5a5e;
}
The icon is this one:
https://www.toptal.com/designers/htmlarrows/symbols/black-diamond-minus-white-x/
You can replace the CSS unicode here: content: "\2756";
with any icon from that site.
The one your example uses is a custom icon.