.qa_title {
    background-color: #ECECEC;
    border-bottom: 1px solid #C5C5C5;
    cursor: pointer;
}
.qa_title, .qa_content {
    position: relative;
    padding: 25px;
    padding-left: 6.5em;
}
.qa_title:before {
    color: #73B9EF;
}
.qa_title:before, .qa_content:before {
    position: absolute;
    content: attr(data-title);
    left: 20px;
    font-weight: bold;
    letter-spacing: .1em;
}
.qa_title:after {
    display: inline-block;
    background-color: #FFF;
    content: '看解答';
    padding: 10px;
    position: absolute;
    left: 20px;
    bottom: 10px;
    font-weight: bold;
    letter-spacing: .1em;
    color: #FF7087;
}
.qa_content {
    max-height: 0;
    padding: 0;
    padding-left: 6.5em;
    overflow: hidden;
    background-color: #C5C5C5;
    -webkit-transition: all .3s;
    -o-transition: all .3s;
    transition: all .3s;
}
.qa_content:before {
    color: #FF7087;
}
.qa_title:before, .qa_content:before {
    position: absolute;
    content: attr(data-title);
    left: 20px;
    font-weight: bold;
    letter-spacing: .1em;
}
.qa_content.show {
    max-height: 1000px;
    padding: 25px;
    padding-left: 6.5em;
    -webkit-transition: all .3s;
    -o-transition: all .3s;
    transition: all .3s;
}
.video-container {
    position: relative;
    padding-bottom: 56.25%;
    padding-top: 30px;
    height: 0;
    overflow: hidden;
}
.video-container iframe, .video-container object, .video-container embed {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}