Pure CSS to achieve click to expand and read the full text function

<div>
    <ul id="content-ul">
        <!-- This is the body of the LI tag that stores the article content-->
    </ul>
</div>

[id^="contTab"] {
    display: none;
}

.content-more {
    display: none;
}

[id^="contTab"]:checked ~ #content {
    max-height: 95px;
    overflow: hidden;
}

[id^="contTab"]:checked ~ .content-more {
    display: block;
    position: relative;
    text-align: center;
}

[id^="contTab"]:checked ~ .content-more .gradient {
    background-image: -webkit-gradient(linear, left top, left bottom, from(rgba(255, 255, 255, 0)), to(#fff));
    background-image: -webkit-linear-gradient(top, rgba(255, 255, 255, 0), #fff);
    background-image: linear-gradient(-180deg, rgba(255, 255, 255, 0), #fff);
    height: 80px;
    position: absolute;
    left: 0;
    top: -79px;
    width: 100%;
}

[id^="contTab"]:checked ~ .content-more .readmore {
    display: inline-block;
    background: #319a1717;
    color: #0014ff9e;
    width: 300px;
    height: 30px;
    border-radius: 32px;
    line-height: 32px;
    font-size: 14px;
    cursor: pointer;
    text-indent: 0;
}

function inner(response) {
    for (var val of response.data) {
        document.getElementById('content-ul').innerHTML += '' +
            '<li>' +
            '<h2 class="title">' + val.title + '</h2>' +
            '<p class="update_author">' + val.author_name + ' / ' + layui.util.toDateString(val.update, "yyyy-MM-dd HH:mm:ss") + '</p>' +
            '<input type="checkbox" id="contTab_' + val.id + '" checked="checked" class="tabbed">' +
            '<div id="content">' + val.content + '</div>' +
            '<div class="content-more"><div class="gradient"></div> <label for="contTab_' + val.id + '" class="readmore">Click to read the full text</label></div>' +
            '</li>'
    }
}