.overlay {
    background: url(../images/overlay.png) no-repeat;
    background-size: 100% 100%;
    box-shadow: none;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}
.lang {
    border: 1px solid rgba(0, 0, 0, 0.5);
    display: block;
    width: 26px;
    height: 26px;
    border-radius: 50%;
    padding: 0;
    transition: all 0.3s ease;
}