header .col-12 {
    /* https://www.geeksforgeeks.org/maintain-the-aspect-ratio-of-a-div-with-css/ */
    /*padding-top: 56.25%;*/
    padding-top: 75%;
    background-image: url('../files/img/floor3-floor-plan.jpg');
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: scroll;
    background-size: cover;
}

/*:target {*/
/*    scroll-margin-top: 20px;*/
/*}*/

#hotspot-1 {
    left: 67%;
    top: 76%;
}

#hotspot-2 {
    left: 51%;
    top: 43%;
}

#hotspot-3 {
    left: 22%;
    top: 33%;
}

#hotspot-4 {
    left: 41%;
    top: 21%;
}

#hotspot-5 {
    left: 52%;
    top: 29%;
}

#hotspot-6 {
    left: 70%;
    top: 37%;
}

#hotspot-7 {
    left: 79%;
    top: 29%;
}

/* 08 */
#hotspot-8 {
    left: 32%;
    top: 21%;
}

/* 09 */
#hotspot-9 {
    left: 56%;
    top: 34%;
}

/* 10 */
#hotspot-10 {
    left: 75%;
    top: 43%;
}

/* 11 */
#hotspot-11 {
    left: 70%;
    top: 63.5%;
}