.modal-window {
     position: fixed;
     background-color: rgba(200, 200, 200, 0.75);
     top: 0;
     right: 0;
     bottom: 0;
     left: 0;
     z-index: 999;
     display:none;
     pointer-events: auto;
     -webkit-transition: all 0.3s;
     -moz-transition: all 0.3s;
     transition: all 0.3s;
 }

.modal-window:target {
    opacity: 1;
    /*pointer-events: auto;*/
}

.modal-window>div {
    width: 400px;
    position: relative;
    margin: 10% auto;
    padding: 2rem;
    background: #fff;
    color: #444;
}

.modal-window header {
    font-weight: bold;
}


.modal-window h1 {
    font-size: 150%;
    margin: 0 0 15px;
}