.ytitem {
position: relative;
display: flex;
justify-content: center;
}

.ytitem .overlay {
position: absolute;
width: 100%;
transition: .5s ease;
background-image: url('../images/play.svg');
height: 100%;
display: block;
background-repeat: no-repeat;
background-position: center center;
background-size: 5%;
}

.ytitem:hover .overlay {
    background-size: 7%;
}