lessons.css

div.item {
    margin: 0 5px 0 5px;
}

div.audio1, div.audio2, div.audio3 {
    cursor: pointer;
}

div.audio1:hover>p {
    background-color: #f1faf1;
}

div.audio2:hover>p {
    background-color: #f1f1fa;
}

div.audio3:hover>p {
    background-color: #faf1f1;
}

div#audio_control {
    position: fixed;
    padding-top: 5px;
    left: 16px;
    top: calc(50%);
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

p.line {
    padding-top: 0;
}

img {
    max-width: 30%;
    max-height: 30%;
    padding-left: 2rem;
}

.header {
    font-size: larger;
}

.tl_v2 {
    display: table-cell;
    padding-right: 1rem;
}

.tr_v2 {
    display: table-cell;
    text-align: right;
    padding-left: 1rem;
    padding-right: 0.2rem;
    border-right: 1px dashed #ccc;
}

ruby>rb, ruby>rt {
    font-size: 8px;
    font-weight: bold;
    color: silver;
}