main
{
    width: 100vw;
    height: 100vh;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
}
    #background
    {
        width: 100%;
        height: auto;
        min-height: 100%;
        display: block;
        position: absolute;
    }
        #background img
        {
            min-width: 100%;
            min-height: 1000px;
            width: auto;
            height: 100vh;
            position: absolute;
            left: 50%;
            transform: translateX(-50%);
        }

    #notice
    {
        width: 350px;
        height: 240px;
        display: flex;
        position: relative;
        z-index: 1;
        justify-content: center;
        align-items: center;
        border-radius: 3px;
        box-shadow: 0 0 -100px white;
        color: white;
        font-size: 2.5em;
        text-shadow: 0 0 5px black;
        text-align: center;
        box-shadow: inset 0 0 2000px rgba(0, 0, 0, .5);
    }