body {
    overflow: auto;
    background-position: center top;
    background-size: cover;
}

#instructions {
    display: none;
    top: 10vh;
    left: 1em;
    width: 90vw;
    box-sizing: border-box;
    background-color: black;
    max-height: 90vh;
    padding: 1em;
    border-radius: .5em;
    overflow: auto;
}

#instructions > .close {
    display: inline-block;
    position: absolute;
    right: 0;
    top: 0;
    line-height: 1.3;
    background-color: red;
    color: white;
    border-radius: 1em;
    width: 1.3em;
    height: 1.3em;
    padding: .15em .15em;
    text-align: center;
}

.h1 {
    font-size: 5vh;
}

.h1 > i {
    display: inline-block;
    height: 1em;
    vertical-align: middle;
    color: blue;
    text-shadow: none;
}