.mark-color-nghiluan {
    color: #3188E1;
    font-family: OpenSansBold, sans-serif;
}
#move-to-child {
    display: inline-block;
    padding: 10px 15px;
    margin-bottom: 10px;
    border: 2px solid #3188E1;
    border-radius: 5px;
    background-color: #f0f8ff;
    font-weight: bold;
    cursor: pointer;
}
#move-to-child i {
    color: #3188E1;
}
.question-child-content,
.question-child-answer {
    margin-top: 10px;
}
.child-answer-item {
    display: flex;
    width: 100%;
    box-sizing: border-box;
    flex-wrap: wrap;
    margin: 5px 0;
    border: 1px solid #DDDDDD;
    padding: 10px 10px 5px;
    border-radius: 5px;
}
.child-answer-key {
    text-transform: uppercase;
    margin-right: 10px;
    font-weight: bold;
}
.ppg-content {
    padding: 5px 10px;
    margin-bottom: 10px;
}
.control-toggle-nl {
    border: 1px solid #3188E1;
    color: #3188E1;
    padding: 10px;
    display: inline-block;
    margin: 0 0 10px 0;
    border-radius: 5px;
    cursor: pointer;
}
.control-toggle-nl img {
    width: 20px;
    height: 20px;
    vertical-align: middle;
    margin-right: 5px;
}
.loigiai {
    background: #F1F8FE;
    padding: 8px 12px;
    position: relative;
    border-radius: 5px;
}
.close-loigiai {
    position: absolute;
    top: 10px;
    right: 20px;
    cursor: pointer;
}
.close-loigiai i {
    color: #3188E1;
}
.solution-suggesstion-title,
.solution-detail-title {
    border-bottom: 1px dotted #DDDDDD;
    padding: 10px 10px 10px 0;
    margin-bottom: 10px;
}
.correct-answer-box {
    display: flex;
}
.correct-answer-box p {
    margin-right: 15px;
    font-weight: bold;
}
.hide {
    display: none;
}
.nlxh-extend {
    background-color: #F8FAFC;
    border: 1px solid #E2E8F0;
    border-radius: 8px;
    padding: 16px 20px;
    margin-top: 15px;
    margin-bottom: 10px;
    box-sizing: border-box;
}
.nlxh-extend-title {
    font-weight: bold;
    font-size: 16px;
    color: #000000;
    border-bottom: 1px solid #E2E8F0;
    padding-bottom: 10px;
    margin-bottom: 12px;
}
.nlxh-extend-content {
    font-size: 15px;
    line-height: 1.6;
    color: #334155;
}
.nlxh-extend-content a {
    color: #2563EB;
    text-decoration: none;
}
.nlxh-extend-content a:hover {
    text-decoration: underline;
}
.nlxh-extend-content p {
    margin-bottom: 8px;
}
.nlxh-extend-content p:last-child {
    margin-bottom: 0;
}