I tried to apply transition property to give an effect when image changes on hover but it seems to not work. Please have a look and help me out.
.ow-outer {
    background-color: #fff;
    width: 200px;
    height: 200px;
    border-radius: 50%;
    border: 1px solid #fff;
    text-align: center;
    padding: 20px;
    background-image: url(../images/team-canada-light.png);
    background-size: 120px;
    background-repeat: no-repeat;
    background-position: center;
    transition: all 0.3s ease-in-out;
}
.ow-outer:hover {
    background-image: url(../images/team-canada.png);
}
 
     
     
    