.av-header::after {
    content: "";
    position: absolute;
    bottom: -16px;
    left: 100%;
    width: 100vw;
    height: 6px;
    transform: translateX(-100%);
    background-color: rgb(120, 173, 202);
}

@media (min-width: 69em){
.av-header::after{
    bottom: -20px;
    height: 6px;
    transform: translateX(-100%);
}
}