body {
    margin: 0;
    padding: 20px;
    background: #fff;
    display: flex;
    width: 100vw;
    height: 100vh;
    align-items: center;
    justify-content: center;
    box-sizing: border-box;
    font-family: sans-serif;
}

.wrap {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
}

.wrap.standby {
    opacity: .2;
}

.wrap img,
.wrap canvas {
    max-width: 100%;
    max-height: 100%;
}

.playButton {
    display: block;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translateX(-50%) translateY(-50%);
    z-index: 1;
    text-decoration: none;
    text-align: center;
    font-size: 72px;
    line-height: 128px;
    color: #fff;
    background: #333;
    border-radius: 50%;
    width: 128px;
    height: 128px;
}

.playButton.hide {
    display: none;
}

.footer {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    width: 100%;
}
.helpWrap {
    position: relative;
}
.help {
    position: absolute;
    bottom: 0;
    right: 0;
    min-width: 40em;
    background: #eee;
    padding: 20px;
    transition: .5s;
    transform: scale(0);
    transform-origin: right bottom;
}
.help.show {
    opacity: 1;
    z-index: 99;
    transform: scale(1);
}