html {
    margin: 0;
    height: 100%;
    overflow: hidden;
}

body {
    margin: 0;
    height: 100%;
    overflow: hidden;
}

iframe {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    border: 0;
}

.white-square {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 100px;
    background: linear-gradient(to top, white 0%, white 40%, transparent 100%);
    z-index: 1000;
    pointer-events: none;
}