* {
    background-clip: border-box;
    box-sizing: border-box;
    font-family: -apple-system, BlinkMacSystemFont, 
                 "Segoe UI", "Roboto", "Oxygen", 
                 "Ubuntu", "Cantarell", "Fira Sans", 
                 "Droid Sans", "Helvetica Neue", sans-serif;
    transition: all 0.2s ease;
    vertical-align: top;
}
body {
    padding: 0;
}
h2 {
    font-variant: small-caps; 
    text-transform: lowercase;
}
input[type="range"] {
    padding: 0.5em;
}

#showHelpCheckbox ~ #overlayDiv {
    background-color: rgba(0, 0, 0, 0.5);
    bottom: 0;
    color: white;
    opacity: 0;
    padding: 1em;
    position: fixed;
    vertical-align: top;
    width: 100%;
}

#showHelpCheckbox:checked ~ #overlayDiv {
    background-color: rgba(0, 0, 0, 0.5);
    bottom: 0;
    color: white;
    opacity: 1;
    position: fixed;
    vertical-align: top;
}

#showHelpLabel {
    cursor: pointer;
    -webkit-user-select: none;  /* Chrome all / Safari all */
    -moz-user-select: none;     /* Firefox all */
    -ms-user-select: none;      /* IE 10+ */
    user-select: none;          /* Likely future */ 
    
/*            border-radius: 0.2em;*/
    background: hsla(60, 90%, 55%, 1);
    display: inline-block;
    padding: 10px;
    padding-right: 40px;
    margin-left: 1em;
}
#showHelpCheckbox {
    position: relative;
    margin-left: -30px;
}
#showHelpLabel:hover, #showHelpCheckbox:hover {
    background: hsla(60, 83%, 74%, 1);
}
#showHelpLabel:active, #showHelpCheckbox:active {
    background: hsla(60, 59%, 50%, 1);
}

/* CONTROLS */

#overlay-ControlsDiv {
    display: inline-block;
    margin-right: 1em;
    max-width: 540px;
    top: 0;
    vertical-align: top;
    width: calc(50% - 2em);
}


.HUDKey {
    transition: none; 
    
    border: 1px solid white;
    border-radius: 0.4em;
    display: inline-block;
    height: 50px;
    line-height: 50px;
    margin-bottom: 5px;
    overflow: hidden;
    text-align: center;
    width: 50px;
}

.HUDKey.activated {
    transition: none;
    
    background-color: hsla(0, 100%, 100%, 0.8);
    box-shadow: inset 0 4px 1px hsla(0, 0%, 0%, 0.5);
    color: hsla(0, 0%, 0%, 0.8);
    line-height: 54px;
}

/* SCENE */

#overlay-SceneDiv {
    display: inline-block;
    margin-left: 1em;
    max-width: 540px;
    top: 0;
    vertical-align: top;
    width: 50%;
}

#overlay-SceneDiv >>> span {
    padding-right: 2em;
}