body {
    padding: 0;
    margin: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    position: fixed;
    background-color: #1b1b1b;
    font-family: sans-serif;
}

canvas {
    display: block;
    width: 100%;
    height: 100%;
}

div#settings {
    position: fixed;
    right: 5px;
    bottom: 5px;
    z-index: 9;

    padding: 0.8em;
    border-radius: 15px;
    background-color: lightgray;
}

div#settings input#lat {
    width: 5.5em;
}

div#startscreen {
    position: fixed;
    top: 15vh;
    left: 20vw;
    height: 60vh;
    width: 60vw;
    
    border-radius: 30px;
    
    background-color: #b1d4ed;
}

div#startscreen h1 {
    font-weight: normal;
    font-family: sans-serif;
    padding-left: 1em;
}

div#startscreen div.desc {
    
    padding-left: 2em;
}

div#startscreen button {
    position: absolute;
    bottom: 3vh;
    right: 3vw;
    font-size: 2.4em;
    
    padding: 0.05em 0.75em;
    
    border-radius: 15px;
}

button.blue-button {
    background-color: #0000;
    border: 2px solid #031c99;
    color: #031c99;
    
    transition: 0.4s ease;
}

button.blue-button:hover {
    background-color: #031c99;
    color: white;
}

button.blue-button:active {
    background-color: #07115e;
    border-color: #07115e;
    color: red;
}

#threejs-canvas { /* Or whatever ID/class your canvas has */
    display: block; /* Removes extra space below canvas if it's an inline element */
    width: 100%;
    height: 100%;
}