A quick demo to get us going.
Add some padding, center the image, then move it down 40px from the top edge. See sub sidebar.
.side {
background: url(https://i.sli.mg/PFinbY.png) no-repeat;
background-position: 50% 10px;
padding-top: 130px;
background-size: 80px auto
}
body.dark .side {
background: url(https://i.sli.mg/non6Yy.png) no-repeat;
background-position: 50% 10px;
padding-top: 130px;
background-size: 80px auto
}
testing code in comment css