Logo besides menu not working

Hi,
i have this code. The link is there but the image doesn’t appear

/* Menu Icons */

@media (min-width: 600px) {
.main-navigation .nav-akusihat-icon {
float: left;
margin-right: 5px;
background: url(images/akusihat-logo.jpg) no-repeat right;
}

.nav-akusihat-icon a {
opacity: 0;
}

}

this is my site – https://www.akusihat.com/

any thing i did wrong?