.single-product #tab-manuals ul {
    padding-left: 0;
}

.single-product #tab-manuals ul.liststyle-pdf {
    margin-left: 0.45em;
    margin-bottom: 0.5em;
    list-style: none;
}

.single-product #tab-manuals ul.liststyle-pdf li {
    position: relative;
    line-height: 1.2;
}

.single-product #tab-manuals ul.liststyle-pdf li::before {
     content: url(../../../../themes/tentacle2/assets/images/pdf-icon.png) " ";
     position: absolute;
     left: -4.9em;
     display: inline-flex;
     display: -webkit-inline-flex;
     display: -ms-inline-flexbox;
     align-items: center;
     bottom: 5px;
     transform: scale(0.24);
 }