.icon-osnov:hover {
    background-image: url("/Content/Images/osnov.png");
    /*opacity: 0.5;*/
    width: 20px;
    height: 20px;
    background-size: 20px;
    background-repeat: no-repeat;
    filter: invert(1);
    background-color:gray;
}

.icon-osnov {
    background-image: url("/Content/Images/osnov.png");
    opacity: 1;
    width: 20px;
    height: 20px;
    background-size: 20px;
    background-repeat: no-repeat;
}
.ikone-slika1 {
    background-image: url("/Content/Images/slika1.png");
    opacity: 1;
    width: 20px;
    height: 20px;
    background-size: 20px;
    background-repeat: no-repeat;
    filter: invert(1);
}