html, body {
    height: 100%;
    width: 100%;
    font-family: sans-serif, Arial;
}

html, body, body * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    overflow-y: hidden;
    overflow-x: hidden;
}

#tap-area {
    height: 90%;
    background: aqua;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: 0.2s ease-in-out background;

    -webkit-touch-callout: none; /* iOS Safari */
    -webkit-user-select: none;  /* Safari */
       -moz-user-select: none;  /* Firefox */
        -ms-user-select: none;  /* Internet Explorer/Edge */
            user-select: none;  
}

#tap-area.tap-bg {
    opacity: 0.5;
}

#tap-area > h1 {
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

h1 > .bpm-label {
    background: white;
    padding: 2px;
    margin-right: 10px;
}

h1 > .bpm-area {
    background: transparent;
}

#tap-controls {
    padding: 1% 5%;
    height: 10%;
    display: flex;
    flex-direction: row;
    align-items: center;
}

#tap-controls > #sample-window-level {
    width: 10%;
    text-align: center;
    margin-right: auto;
}
#tap-controls > #sample-window-slider {
    width: 50%;
    margin-left: auto;
}
#tap-controls > #sample-window-level
#tap-controls > #sample-window-slider {
    height: 100%;
}

img#volume-level-icon {
    display: inline-block;
    position: absolute;
    text-align: center;
    background: whitesmoke;
    top: 1%;
    right: 5%;
    color: gray;
    font-size: 3em;
    width:10%;
    padding: 2%;
}