.container {
        position: relative;
    }
    .lesson_subject_list {}
    .lesson_subject_item {
        margin: 0;
        float: left;
    }
    .lesson_subject_item a {
        text-align: center;
        display: block;
        margin: 5px;
        padding: 10px;
        font: bold 17px OpenSansCondensed;
        color: navy;
        background: #E2F1F4;
        border: 1px solid #ccc;
        -moz-border-radius: 3px;
            -webkit-border-radius: 3px;
            border-radius: 3px;
    }
    .lesson_subject_item a:hover {
        border: 1px solid navy;
        color: navy;
    }
    .lesson_subject_item img {
        margin-bottom: 10px;
        border: 0;
    }

    .lesson_class_h2 {
        font-family: 'DDC';
        color: red;
        font-size: 30px;
        text-shadow: #8b8a8a 1px 1px 1px;
        float: left;
    }

    /* Trello */
    .trello {
        margin: 0 0 10px 0;
        padding: 10px 0 5px 0;
    }
    
    .trello:nth-child(5n+1) {
        background-color: #007957;
    }
    
    .trello:nth-child(5n+2) {
        background-color: #CD0404;
    }
    
    .trello:nth-child(5n+3) {
        background-color: royalblue;
    }
    
    .trello:nth-child(5n+4) {
        background-color: #3A1078;
    }
    
    .trello:nth-child(5n) {
        background-color: #FC7300;
    }
    
    .trello h3 {
        color: #fff;
        font-size: 17px;
        margin: 0 0 10px 10px;
    }
    
    .trello_item {
        display: block;
        font-family: 'Charm';
        font-size: 18px;
        line-height: 25px;
        background: #fff;
        padding: 7px 5px;
        margin: 0 10px 5px 10px;
        text-align: justify;
        border-radius: 3px;
        -webkit-box-shadow: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
        box-shadow: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
        transition: all 0.3s cubic-bezier(.25, .8, .25, 1);
    }
    .trello a {
        color: red;
        font-weight: bold;
    }
    .trello_item a:hover {
        color: blue;
    }
    .trello_item:hover {
        background: yellow;
    }

    #lesson_post_cover {
        background-image: url(img/Chalkboard-background-powerpoint.jpg);
        background-repeat: no-repeat;
        background-size: cover;
        background-position: center bottom;
        margin-top: -40px;
        margin-bottom: 10px;
    }
    #lesson_post_cover .container {
        position: relative;
    }
    #lesson_post_cover .container h1 {
        max-width: 650px;
        font-family: 'Triumph';
        font-size: 40px;
        line-height: 40px;
        color: white;
        padding-top: 40px;
        text-align: justify;
    }
    #lesson_post_cover .container h5 {
        max-width: 650px;
        font-family: 'Triumph';
        font-size: 20px;
        line-height: 30px;
        color: yellow;
        text-align: justify;
    }
    #lesson_post_cover_teacher {
        font-weight: bold;
        font-size: 16px;
        height: 60px;
    }
    #lesson_post_cover_teacher a {
        color: #fff;
    }
    #lesson_post_cover_teacher a:hover {
        color: yellow;
    }
    #lesson_post_cover_teacher img {
        border: 0;
        width: 50px;
        height: 50px;
        margin-top: -15px;
        margin-right: 10px;
        float: left;
        -moz-border-radius: 50%;
            -webkit-border-radius: 50%;
            border-radius: 50%;
    }

    .lesson_post_breadcrumb {
        margin-bottom: 20px;
    }

    .course_list {
        font-family: 'Muli','Arial';
        margin: 0px;
    }
    .course {
        width: 100%;
        background: #FFF;
        border-radius: 4px;
        box-shadow: 0px 5px 10px rgba(0, 0, 0, 0.2);
        overflow: hidden;
    	margin-bottom: 15px;
    }
    .course-info {
        background: #ED474A;
        color: #FFF;
        padding: 30px;
    }
    .course-progress {
        padding: 30px;
        position: relative;
    }
    .course h2 {
        letter-spacing: 1px;
        margin: 10px 0px;
    }
    .course h5 {
        letter-spacing: 1px;
        margin: 40px 0 10px 0px;
        font-weight: normal;
        font-size: 16px;
        text-align: justify;
    }
    .course h6 {
        margin: 0;
        font-size: 13px;
    }
    .course-info img {
        float: left;
        width: 30px;
        border: 0;
        margin: -5px 5px 0 0;
        -moz-border-radius: 2px;
            -webkit-border-radius: 2px;
            border-radius: 2px;
    }
    .course-info a {
        color: rgb(166, 251, 163);
        display: inline-block;
        font-size: 14px;
        opacity: 0.8;
        margin-top: 30px;
        text-decoration: none;
    }
    .course-info a:hover {
        color: gainsboro;
    }
    .progress-container {
        float: left;
        margin: 0;
        width: 45%;
    }
    .progress {
        background: #DDD;
        border-radius: 3px;
        height: 5px;
        width: 100%;
        position: relative;
    }
    .progress::after {
        border-radius: 3px;
        background: #ED474A;
        content: '';
        position: absolute;
        top: 0px;
        left: 0px;
        height: 5px;
        width: var(--progress-width, 0%); /* Mặc định là 30% */
        transition: width 1s ease-in-out; /* Thời gian và hiệu ứng chuyển đổi */
    }
    .progress-text {
        font-size: 12px;
        opacity: 0.8;
        letter-spacing: 1px;
    }
    .btn {
        background: #ED474A;
        border: 0px;
        outline: none;
        box-shadow: 0px 10px 10px rgba(0, 0, 0, 0.2);
        color: #FFF;
        font-size: 16px;
        padding: 12px 25px;
        float:inline-end;
        margin: 0 0 -10px 0;
        cursor: pointer;
        letter-spacing: 1px;
        -moz-border-radius: 5px;
            -webkit-border-radius: 5px;
            border-radius: 5px;
    }

    .tred {
        background: red;
    }
    .tgreen {
        background: green;
    }
    .tblue {
        background: blue;
    }
    
    a.action_btn {
        display: inline-block;
        font-weight: bold;
        color: #fff;
        font-size: 13px;
        margin: -5px 0 0 2px;
        padding: 3px 10px;
            -moz-border-radius: 4px;
            -webkit-border-radius: 4px;
            border-radius: 4px;
    }
    a.action_btn:hover {
        color: #fff;
        background: #018CC5;
    }
    a.action_btn span {
        border: 1px dashed #fff;
        display: block;
        padding: 3px 10px;
        margin: -2px -9px;
        border-radius: 4px;
    }

    .prac_post_item {
        padding: 0 10px 10px 10px;
        margin: 0 0 10px 0;
    }
    .prac_post_item_level {
		height: 20px;
		width: 35px;
		float: right;
		margin: 5px -10px 0 10px;
		padding: 4px 0 5px 15px;
		color: #fff;
		font-weight: bold;
		font-size: 13px;
	}
	.prac_post_item_level_1 {
		background: url(img/prac_post_level_1.png) no-repeat;
	}
	.prac_post_item_level_2 {
		background: url(img/prac_post_level_2.png) no-repeat;
	}
	.prac_post_item_level_3 {
		background: url(img/prac_post_level_3.png) no-repeat;
	}

    .box {
        font-family: SVN-Georgia;
        font-size: 16px;
    }

    .post_target_list {
        list-style: none;
        counter-reset: target;
        margin-left: -40px;
        columns: 2;
        -webkit-columns: 2;
        -moz-columns: 2;
    }
    .post_target_list li {
        counter-increment: target;
        margin: 0 0 10px 30px;
        text-align: justify;
    }
    .post_target_list li::before {
        margin-left: -30px;
        margin-right: 5px;
        content: counter(target);
        padding: 0 2px;
        background: darkgreen;
        border-radius: 100%;
        color: white;
        width: 1.2em;
        text-align: center;
        display: inline-block;
    }

    table td, table th {
        padding: 10px;
    }
    #lesson_section_table {
        margin: 20px 0;
        border-spacing: 0;
        width: 100%;
        border: solid #ccc 1px;
        -moz-border-radius: 6px;
        -webkit-border-radius: 6px;
        border-radius: 6px;
        -webkit-box-shadow: 0 1px 1px #ccc; 
        -moz-box-shadow: 0 1px 1px #ccc; 
        box-shadow: 0 1px 1px #ccc;         
    }
    #lesson_section_table tr:hover {
        background: #fbf8e9;
        -o-transition: all 0.1s ease-in-out;
        -webkit-transition: all 0.1s ease-in-out;
        -moz-transition: all 0.1s ease-in-out;
        -ms-transition: all 0.1s ease-in-out;
        transition: all 0.1s ease-in-out;     
    }    
    #lesson_section_table td, #lesson_section_table th {
        border-left: 1px solid #ccc;
        border-top: 1px solid #ccc;
        text-align: left;    
    }
    #lesson_section_table th {
        background-color: #dce9f9;
        background-image: -webkit-gradient(linear, left top, left bottom, from(#ebf3fc), to(#dce9f9));
        background-image: -webkit-linear-gradient(top, #ebf3fc, #dce9f9);
        background-image:    -moz-linear-gradient(top, #ebf3fc, #dce9f9);
        background-image:     -ms-linear-gradient(top, #ebf3fc, #dce9f9);
        background-image:      -o-linear-gradient(top, #ebf3fc, #dce9f9);
        background-image:         linear-gradient(top, #ebf3fc, #dce9f9);
        -webkit-box-shadow: 0 1px 0 rgba(255,255,255,.8) inset; 
        -moz-box-shadow:0 1px 0 rgba(255,255,255,.8) inset;  
        box-shadow: 0 1px 0 rgba(255,255,255,.8) inset;        
        border-top: none;
        text-shadow: 0 1px 0 rgba(255,255,255,.5); 
    }
    #lesson_section_table td:first-child, #lesson_section_table th:first-child {
        border-left: none;
    }
    #lesson_section_table th:first-child {
        -moz-border-radius: 6px 0 0 0;
        -webkit-border-radius: 6px 0 0 0;
        border-radius: 6px 0 0 0;
    }
    #lesson_section_table th:last-child {
        -moz-border-radius: 0 6px 0 0;
        -webkit-border-radius: 0 6px 0 0;
        border-radius: 0 6px 0 0;
    }
    #lesson_section_table th:only-child{
        -moz-border-radius: 6px 6px 0 0;
        -webkit-border-radius: 6px 6px 0 0;
        border-radius: 6px 6px 0 0;
    }
    #lesson_section_table tr:last-child td:first-child {
        -moz-border-radius: 0 0 0 6px;
        -webkit-border-radius: 0 0 0 6px;
        border-radius: 0 0 0 6px;
    }
    #lesson_section_table tr:last-child td:last-child {
        -moz-border-radius: 0 0 6px 0;
        -webkit-border-radius: 0 0 6px 0;
        border-radius: 0 0 6px 0;
    }
    #lesson_section_table tr td:first-child {
        width: 40px;
        text-align: center;
    }
    #lesson_section_table tr td:last-child {
        width: 110px;
    }

    .lesson_part_table tr td {
        padding: 0;
        line-height: 0;
    }
    .lesson_part_table td select {
        border: 0;
        width: 100%;
        margin: 0;
    }
    .lesson_part_table tr td:last-child {
        width: auto;
    }

    .lesson_section_title {
        padding: 10px 10px 5px 0;
        background-color: #B3E5A1;
        font: 23px DDC;
        color: red;
        font-weight: bold;
        -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
        border-radius: 3px;
        display:flex;
    }
    .lesson_section_title:hover {
        cursor: hand;
    }
    .lesson_section_title span {
        display: inline-block;
        margin: -10px 25px -5px 0;
        padding: 10px 10px 5px 15px;
        background-color: #196B24;
        font: 23px DDC;
        color: white;
        font-weight: bold;
        position: relative;
        border-top-left-radius: 3px;
        border-bottom-left-radius: 3px;
    }
    .lesson_section_title span:after {
        content: "";  
        border-top: 19.4px solid transparent;
        border-bottom: 19.4px solid transparent;
        border-left: 19.4px solid #196B24;
        position: absolute;
        right: -19.3px;
        top: 0;
    }
    .lesson_section_content {
        font-family: SVN-Georgia;
        font-size: 18px;
        line-height: 28px;
        position: relative;
    }
    .lesson_section_content p {
        margin: 20px 0;
    }
    .lesson_section_content:hover .lesson_section_content_control {
        visibility: visible;
    }
    .lesson_section_content_control {
        width: 30px;
        position: absolute;
        top: 5px;
        left: -30px;
        visibility: hidden;
    }
    .lesson_section_content_control img {
        border: 0;
        width: 25px;
        margin-bottom: 5px;
    }
    .lesson_section_content_text {
        text-align: justify;
    }
    .lesson_section_content_text h2 {
        color: navy;
        font: bold 22px Azuki;
        text-shadow: 0 1px white, 0 2px #777;
    }
    .lesson_section_content_text_border {
        padding: 10px;
        text-align: justify;
        border: 1px solid magenta;
        -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
        border-radius: 3px;
    }

    .lesson_section_content_colorbox {
        margin: 10px 0;
    }
    .colorbox_info {
        background-color: blue;
        background-image: url(img/icon_section_content_colorbox_info.png);
        background-repeat: no-repeat;
        background-position: 10px center;
        background-size: 30px;
        padding: 2px 0;
        -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
        border-radius: 3px;
    }
    .colorbox_info .lesson_section_content_colorbox_title {
        margin: 0 2px 0 50px;
        background-color: #ffffff;
        padding: 10px 10px 0 10px;
        font-weight: bold;
        color: blue;
        border-top-left-radius: 3px;
        border-top-right-radius: 3px;
    }
    .colorbox_info .lesson_section_content_colorbox_content {
        margin: 0 2px 0 50px;
        background-color: #ffffff;
        padding: 5px 10px;
        border-bottom-left-radius: 3px;
        border-bottom-right-radius: 3px;
    }
    .colorbox_warning {
        background-color: darkorange;
        background-image: url(img/icon_section_content_colorbox_warning.png);
        background-repeat: no-repeat;
        background-position: 10px center;
        background-size: 30px;
        padding: 2px 0;
        -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
        border-radius: 3px;
    }
    .colorbox_warning .lesson_section_content_colorbox_title {
        margin: 0 2px 0 50px;
        background-color: #ffffff;
        padding: 10px 10px 0 10px;
        font-weight: bold;
        color: darkorange;
        border-top-left-radius: 3px;
        border-top-right-radius: 3px;
    }
    .colorbox_warning .lesson_section_content_colorbox_content {
        margin: 0 2px 0 50px;
        background-color: #ffffff;
        padding: 5px 10px;
        border-bottom-left-radius: 3px;
        border-bottom-right-radius: 3px;
    }
    .colorbox_error {
        background-color: #CD0404;
        background-image: url(img/icon_section_content_colorbox_error.png);
        background-repeat: no-repeat;
        background-position: 10px center;
        background-size: 30px;
        padding: 2px 0;
        -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
        border-radius: 3px;
    }
    .colorbox_error .lesson_section_content_colorbox_title {
        margin: 0 2px 0 50px;
        background-color: #ffffff;
        padding: 10px 10px 0 10px;
        font-weight: bold;
        color: #CD0404;
        border-top-left-radius: 3px;
        border-top-right-radius: 3px;
    }
    .colorbox_error .lesson_section_content_colorbox_content {
        margin: 0 2px 0 50px;
        background-color: #ffffff;
        padding: 5px 10px;
        border-bottom-left-radius: 3px;
        border-bottom-right-radius: 3px;
    }
    .colorbox_paper {
        background-color:#FFF;
        color:#222;
        resize:none;
        line-height:40px;
        padding-left:100px;
        padding-right:20px;
        padding-top:12px;
        padding-bottom:25px;
        background-image:url(img/bg_section_content_colorbox_paper_lines.png), url(img/bg_section_content_colorbox_paper_blank.png);
        background-repeat:repeat-y, repeat;
        -webkit-border-radius:3px;
        border-radius:3px;
        -webkit-box-shadow: 0px 2px 14px #000;
        box-shadow: 0px 2px 14px #000;
        border-top:1px solid #FFF;
        border-bottom:1px solid #FFF;
    }
    .colorbox_paper .lesson_section_content_colorbox_title {
        margin: 0;
        font-weight: bold;
        color: magenta;
    }
    .colorbox_paper .lesson_section_content_colorbox_content {
        margin: 0;
    }
    .colorbox_corner {
        position: relative;
        padding: 20px;
        text-align: justify;
        overflow: hidden;
        color: #272727;
        background: #ffc600;
        background: linear-gradient(225deg, transparent 42px, #ffc600 42px);
        border-radius: 10px;
    }
    .colorbox_corner:before {
        content: "";
        display: block; 
        width: 0;
        position: absolute;
        top: -1px;
        right: -1px;
        border: 30px solid transparent;
        border-bottom-left-radius: 10px;
        border-left: 30px solid #ffc600;
        border-bottom: 30px solid #ffc600;  
        box-shadow: 0px 2px 4px rgba(0,0,0,0.4), -1px 1px 4px rgba(0,0,0,0.4);
    }
    .colorbox_corner .lesson_section_content_colorbox_title {
        margin: 0;
        font-weight: bold;
        color: red;
    }
    .colorbox_corner .lesson_section_content_colorbox_content {
        margin: 0;
    }

    details {
        margin-bottom: 10px;
    }
    .lesson_section_content_toggle_title {
        font-weight: bold;
        color: darkgreen;
        font-style: italic;
        margin-top: 10px;
    }
    .lesson_section_content_toggle_title:hover {
        cursor: pointer;
    }
    .lesson_section_content_toggle_content {
        position: relative;
        margin-top: 15px;
        padding: 0 10px;
        text-align: justify;
        border: 1px solid #58b666;
    	background: #ffffff;
        -moz-border-radius: 3px;
            -webkit-border-radius: 3px;
            border-radius: 3px;
    }
    .lesson_section_content_toggle_content_arrow {
        position:absolute;
        width:15px;
        height:15px;
        background: #ffffff;
        border-left:1px solid #58b666;
        border-top:1px solid #58b666;
        transform:rotate(45deg);
        top:-8px;
        left:30px;
    }
    .lesson_section_content img, .lesson_section_content_toggle_content img {
        max-width: 100%;
    }
    .lesson_section_content_text ul, .lesson_section_content_colorbox ul, .lesson_section_content_toggle_content ul {
        padding-left: 15px;
    }
    .lesson_section_content .MathJax_CHTML {
        font-size: 19px !important;
    }
    .lesson_section_panel {
        border: 1px solid #ccc;
        -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
        border-radius: 3px;
    }
    .lesson_section_panel_menu {
        margin: 0;
        display: grid;
        grid-template-columns: repeat(11, 1fr);
    }
    .lesson_test_panel_menu {
        grid-template-columns: repeat(3, 1fr);
    }
    .lesson_section_panel_menu img {
        border: 0;
        width: 20px;
    }
    .lesson_test_panel_menu img {
        border: 0;
        width: 32px;
    }
    .lesson_section_panel_menu a {
        display: inline-block;
        text-align: center;
        padding: 5px;
    	border-bottom: 1px solid #ccc;
    }
    .lesson_test_panel_menu a {
        border-right: 1px solid #ccc;
    }
    .lesson_test_panel_menu a:last-child {
        border-right: 0;
    }
    .lesson_section_panel_menu a:hover {
        background-color: #B3E5A1;
    }
    .lesson_section_panel_menu a.active {
        background-color: #fff;
        border: 1px solid #ccc;
        border-bottom: 1px solid #fff;
        border-top-left-radius: 3px;
        border-top-right-radius: 3px;
        margin-top: 1px;
        margin-bottom: -0.5px;
    }
    .lesson_section_panel_form {
        display: none;
        background-color: #fff;
        padding: 10px;
        border-bottom-left-radius: 3px;
        border-bottom-right-radius: 3px;
    }
    .lesson_section_panel_form h3 {
        margin: 0 0 10px 0;
        text-transform: uppercase;
    }

    .timelines {
        counter-reset: timeline-counter;
        margin-left: 40px;
        position: relative;
        padding-top: 0;
    }
    .timelines:before {
        content: "";
        display: block;
        top: 1rem;
        left: -1.5rem;
        position: absolute;
        height: calc(100% - 20px);
        width: 2px;
        background-color: #ccc;
    }
    .timeline {
        position: relative;
        padding-left: 0.5rem;
    }
    .timeline-title {
        font-size: 18px;
    }
    .timeline-intro {
        margin-top: -10px;
        text-align: justify;
    }
    .timeline-counter {
        padding-bottom: 5px;
    }
    .timeline-counter .timeline-title:before {
        position: absolute;
        top: -5px;
        left: -2.5rem;
        display: block;
        height: 2rem;
        width: 2rem;
        border-radius: 50%;
        border: 0.125rem solid #ccc;
        display: flex;
        background-color: #fff;
        align-items: center;
        justify-content: center;
        counter-increment: timeline-counter;
        content: counter(timeline-counter);
        font-size: 18px;
        font-weight: bold;
    }

    .tooltip {
        position: absolute;
        z-index: 1070;
        display: block;
        font-size: 16px;
        font-style: normal;
        font-weight: normal;
        line-height: 1.42857143;
        text-align: left;
        text-align: start;
        text-decoration: none;
        text-shadow: none;
        text-transform: none;
        letter-spacing: normal;
        word-break: normal;
        word-spacing: normal;
        word-wrap: normal;
        white-space: normal;
        filter: alpha(opacity=0);
        opacity: 0;
      
        line-break: auto;
    }
    .tooltip.in {
        filter: alpha(opacity=90);
        opacity: .9;
    }
    .tooltip.top {
        padding: 5px 0;
        margin-top: -3px;
    }
    .tooltip.right {
        padding: 0 5px;
        margin-left: 3px;
    }
    .tooltip.bottom {
        padding: 5px 0;
        margin-top: 3px;
    }
    .tooltip.left {
        padding: 0 5px;
        margin-left: -3px;
    }
    .tooltip-inner {
        max-width: 400px;
        padding: 3px 8px;
        color: #fff;
        text-align: center;
        background-color: #000;
        border-radius: 4px;
    }
    .tooltip-arrow {
        position: absolute;
        width: 0;
        height: 0;
        border-color: transparent;
        border-style: solid;
    }
    .tooltip.top .tooltip-arrow {
        bottom: 0;
        left: 50%;
        margin-left: -5px;
        border-width: 5px 5px 0;
        border-top-color: #000;
    }
    .tooltip.top-left .tooltip-arrow {
        right: 5px;
        bottom: 0;
        margin-bottom: -5px;
        border-width: 5px 5px 0;
        border-top-color: #000;
    }
    .tooltip.top-right .tooltip-arrow {
        bottom: 0;
        left: 5px;
        margin-bottom: -5px;
        border-width: 5px 5px 0;
        border-top-color: #000;
    }
    .tooltip.right .tooltip-arrow {
        top: 50%;
        left: 0;
        margin-top: -5px;
        border-width: 5px 5px 5px 0;
        border-right-color: #000;
    }
    .tooltip.left .tooltip-arrow {
        top: 50%;
        right: 0;
        margin-top: -5px;
        border-width: 5px 0 5px 5px;
        border-left-color: #000;
    }
    .tooltip.bottom .tooltip-arrow {
        top: 0;
        left: 50%;
        margin-left: -5px;
        border-width: 0 5px 5px;
        border-bottom-color: #000;
    }
    .tooltip.bottom-left .tooltip-arrow {
        top: 0;
        right: 5px;
        margin-top: -5px;
        border-width: 0 5px 5px;
        border-bottom-color: #000;
    }
    .tooltip.bottom-right .tooltip-arrow {
        top: 0;
        left: 5px;
        margin-top: -5px;
        border-width: 0 5px 5px;
        border-bottom-color: #000;
    }

    .showNextSectionContent {
        padding: 10px 50px;
        font-size: 15px;
        cursor: pointer;
    }
    .ex_box_test_stat {
        font-size: 14px;
        color: #2b2a2a;
    }

    .lesson_section_content mark {
        padding: 0px 2px 1px 2px;
    }
    .lesson_section_content mark:nth-of-type(5n) {
        background-color:yellow;
    }
    .lesson_section_content mark:nth-of-type(5n+1) {
        background-color:lightgreen;
    }
    .lesson_section_content mark:nth-of-type(5n+2) {
        background-color:lightpink;
    }
    .lesson_section_content mark:nth-of-type(5n+3) {
        background-color:cyan;
    }
    .lesson_section_content mark:nth-of-type(5n+4) {
        background-color:rgb(248, 127, 248);
    }

    .section_content_table {
        border-collapse: collapse;
        margin: 10px 0;
        width: 100%;
        font-family: SVN-Georgia;
        font-size: 16px;
        box-shadow: 0 0 20px rgba(0, 0, 0, 0.15);
        border: 1px solid #009879;
        border-left: 2px;
        border-right: 2px;
        border-bottom: 2px;
        -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
        border-radius: 3px;
        overflow: hidden;
    }
    .section_content_table thead tr {
        background-color: #009879;
        color: #ffffff;
        text-align: left;
    }
    .section_content_table th {
        padding: 10px 5px;
        border: 1px solid #17edc3;
        text-align: center;
    }
    .section_content_table td {
        padding: 10px 5px;
        border: 1px solid #009879;
        font-size: 16px;
        text-align: center;
    }
    .section_content_table tr td:first-child {
        text-align: left;
    }
    .section_content_table tbody tr:nth-of-type(even) {
        background-color: #f3f3f3;
    }

    .ex_box {
        margin: 20px 0 10px 0;
        background: #fff;
        border: 1px solid #3700B3;
        border-radius: 3px;
        box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 
                0 6px 20px 0 rgba(0, 0, 0, 0.19);
    }
    .ex_box h3 {
        margin: 0;
        padding: 5px 0 5px 10px;
        font-size: 16px;
        background-color: #3700B3;
        color: #ffffff;
        box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.2), 
                0 1.5px 2px 0 rgba(0, 0, 0, 0.19);
    }
    .ex_box h3 img {
        border: 0;
        width: 20px;
        float: right;
        margin-top: -5px;
        padding: 9px 10px;
    }
    .ex_box h3 img:hover {
        background-color: #723af4;
    }
    .ex_box_test {
        margin: 0;
        padding: 0 10px;
    }
    .ex_box_test_content {
        text-align: justify;
    }
    .ex_box_test img {
        max-width: 100%;
    	border-radius: 5px;
    }
    .ex_box_test_solution {
        margin: 20px 0 10px 0;
        padding: 0 10px;
        text-align: justify;
        border: 1.5px dashed #ccc;
        border-radius: 5px;
    }
    .radio-container {
        margin: 10px auto;
    }
    .radio-label {
        background: white;
        border: 1px solid #ccc;
        border-radius: 5px;
        box-shadow: 0 2px 4px rgba(0,0,0,0.05);
        cursor: pointer;
        display: block;
        margin: 0 auto 10px;
        padding: 10px 10px 10px 50px;
        position: relative;
        transition: .3s ease all;
    }
    .radio-label:hover {
        box-shadow: 0 4px 8px rgba(0,0,0,0.05);
        background-color: lightcyan;
    }
    .radio-label:before {
        background: #eee;
        border-radius: 50%;
        content:'';
        height: 30px;
        left: 10px;
        position: absolute;
        top: calc(50% - 15px);
        transition: .3s ease background-color;
        width: 30px;
    }
    .radio-label span {
        -webkit-user-select: none;
        -moz-user-select: none;
        user-select: none;
    }
    .radio-btn {
        position: absolute;
        visibility: hidden;
    }
    .radio-btn:checked + .radio-label {
        background: #ECF5FF;
        border-color: #4A90E2;
    }
    .radio-btn:checked + .radio-label:before {
        background-color: #4A90E2;
        background-image:  url('data:image/svg+xml;base64,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');
        background-repeat: no-repeat;
        background-position: center;
        background-size: 15px;
    }
    .radio-btn.positive:checked + .radio-label {
        background: #EAFFF6;
        border-color: #32B67A;
    }
    .radio-btn.positive:checked + .radio-label:before {
        background-color: #32B67A;
    }
    .radio-btn.neutral:checked + .radio-label:before {
        background-image: url('data:image/svg+xml;base64,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');
    }
    .radio-btn.negative:checked + .radio-label {
        background: #FFF2F2;
        border-color: #E75153;
    }
    .radio-btn.negative:checked + .radio-label:before {
        background-color: #E75153;
        background-image: url('data:image/svg+xml;base64,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');
    }
    .checkbox-label:before {
        border-radius: 0;
    }
    .checkbox-btn:checked + .checkbox-label:before {
        border-radius: 0;
    }

    .pair_container {
        margin-bottom: 10px;
    }
    .pair_column_left {
        float: left;
        width: 49%;
    }
    .pair_column_right {
        float: right;
        width: 49%;
    }
    .pair_item {
        padding: 10px;
        margin: 7px 0;
        cursor: pointer;
        background-color: rgb(254, 254, 252);
        transition: background-color 0.3s, transform 0.2s;
        border: 1px solid #ccc;
        -moz-border-radius: 3px;
        -webkit-border-radius: 3px;
        border-radius: 3px;
    }
    .pair_item:hover {
        background-color: #e6f4c3;
        transform: scale(1.03);
    }
    .pair_item.selected {
        background-color: #dcf8be;
        border: 1px solid #ddd;
    }
    .pair_item.correct {
        background-color: lightgreen; /* Màu xanh cho đúng */
        pointer-events: none;
    }
    .pair_item.incorrect {
        background-color: #d3d3d3; /* Màu xám cho sai */
        pointer-events: none;
    }
    /* Màu sắc khác nhau cho từng cặp đúng */
    .pair_container_finish .pair_item.correct-1 { background-color: rgb(244, 244, 96); }
    .pair_container_finish .pair_item.correct-2 { background-color: rgb(251, 180, 251); }
    .pair_container_finish .pair_item.correct-3 { background-color: lightskyblue; }
    .pair_container_finish .pair_item.correct-4 { background-color: lightcyan; }
    .pair_container_finish .pair_item.correct-5 { background-color: lightpink; }
    .pair_container_finish .pair_item.correct-6 { background-color: lightgreen; }
    .pair_result {
        margin: 10px 0;
        color: magenta;
        text-align: center;
        border: 1px solid red;
        padding: 10px;
    }

    #missForm select {
        border: 0;
        border-bottom: 1px dashed #656363;
        padding: 0;
        font-family: SVN-Georgia;
        font-size: 18px;
        line-height: 28px;
        color: red;
    }
    .ex_box_essay_answer {
        margin: 20px 0;
        text-align: right;
        font-weight: bold;
    }
    .ex_box_essay_answer .ex_box_essay_answer_input {
        display: inline-block;
        padding: 0px 15px 5px 15px;
        border: 1px solid magenta;
        border-radius: 3px;
        min-width: 50px;
        text-align: center;
    }

    #form_exam_list_do {
        margin: 10px 0;
    }
    #form_exam_list_do ul {
        padding: 10px 10px 10px 25px;
        background-color: #dcf8be;
        border-left: 5px solid #FC7300;
        border-top-right-radius: 3px;
        border-bottom-right-radius: 3px;
    }
    #form_exam_list_do ul li {
        list-style-type: '\2139';
        padding-left: 5px;
    }

    .lesson_exam_part {
        margin-top: 20px;
        padding: 5px;
        background-color: #018CC5;
        border: 1px solid #018CC5;
        border-radius: 3px;
        box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 
                0 6px 20px 0 rgba(0, 0, 0, 0.19);
    }
    .lesson_exam_part_header {
        color: #fff;
        margin: 5px 10px 10px 10px;
        cursor: pointer;
    }
    .lesson_exam_part_container {
        padding: 5px 10px;
        background-color: #fff;
        border-radius: 3px;
        box-shadow: inset 2px 2px 4px rgba(0, 0, 0, 0.4);
    }
    .lesson_exam_part_content {
        text-align: justify;
        font-family: SVN-Georgia;
        font-size: 16px;
        margin-bottom: 10px;
    }
    .lesson_exam_part_panel {
        margin: 10px 0;
        border-top: 1px solid #ccc;
        border-bottom: 1px solid #ccc;
    }
    .lesson_exam_part_panel a {
        display: inline-block;
        padding: 5px;
        margin: 1px 15px 0 0;
        color: #000;
        font-size: 14px;
        border: 1px solid #fff;
        border-radius: 3px;
    }
    .lesson_exam_part_panel a:hover {
        border-color: #3700B3;
        color: #000;
    }
    .lesson_exam_part_panel img {
        float: left;
        width: 20px;
        border: 0;
        margin-right: 5px;
    }
    ul.filters {
        float: right;
        display: block;
        margin: 0;
        padding: 1px 0 0 0;
    }
    ul.filters > li {
        list-style: none;
        display: inline-block;
    }
    ul.filters > li > a {
        display: block;
        color: #434e5e;
        text-decoration: none;
        padding: 5px 10px;
        margin: 0;
        border: 0;
    }
    ul.filters > li > a:hover {
        background-color: #e6e9ed;
    }
    ul.filters > li.active > a {
        color: #fff;
        background-color: rgba(252, 41, 74, 1);
    }
    .lesson_exam_post_item {
        margin: 20px 0;
    }
    .lesson_exam_post_item_container {
        padding: 0 10px 20px 10px;
        border-radius: 3px;
        position: relative;
    }
    .lesson_exam_post_item_level_1 {
        border: 1px solid darkgreen;
        border-bottom: 2px solid darkgreen;
        border-right: 2px solid darkgreen;
    }
    .lesson_exam_post_item_level_2 {
        border: 1px solid darkmagenta;
        border-bottom: 2px solid darkmagenta;
        border-right: 2px solid darkmagenta;
    }
    .lesson_exam_post_item_level_3 {
        border: 1px solid darkred;
        border-bottom: 2px solid darkred;
        border-right: 2px solid darkred;
    }
    .lesson_exam_post_item_ribbon {
        position: absolute;
        top: -6.1px;
        left: 20px;
    }
    .lesson_exam_post_item_ribbon span {
        position: relative;
        display: block;
        text-align: center;
        background: #F8463F;
        font-size: 14px;
        line-height: 1;
        padding: 10px 0 10px 0;
        border-top-right-radius: 8px;
        border-bottom-right-radius: 5px;
        border-bottom-left-radius: 5px;
        width: 105px;
        color: #fff;
    }
    .lesson_exam_post_item_ribbon span:before, .lesson_exam_post_item_ribbon span:after {
        position: absolute;
        content: "";
    }
    .lesson_exam_post_item_ribbon span:before {
       height: 6px;
       width: 6px;
       left: -6px;
       top: 0;
       background: #F8463F;
    }
    .lesson_exam_post_item_ribbon span:after {
       height: 6px;
       width: 8px;
       left: -8px;
       top: 0;
       border-radius: 8px 8px 0 0;
       background: #C02031;
    }
    .lesson_exam_post_item_level_1 .lesson_exam_post_item_ribbon span {
        background: darkgreen;
    }
    .lesson_exam_post_item_level_1 .lesson_exam_post_item_ribbon span:before {
       background: darkgreen;
    }
    .lesson_exam_post_item_level_1 .lesson_exam_post_item_ribbon span:after {
       background: rgb(0, 53, 0);
    }
    .lesson_exam_post_item_level_2 .lesson_exam_post_item_ribbon span {
        background: darkmagenta;
    }
    .lesson_exam_post_item_level_2 .lesson_exam_post_item_ribbon span:before {
       background: darkmagenta;
    }
    .lesson_exam_post_item_level_2 .lesson_exam_post_item_ribbon span:after {
       background: rgb(74, 0, 74);
    }
    .lesson_exam_post_item_level_3 .lesson_exam_post_item_ribbon span {
        background: darkred;
    }
    .lesson_exam_post_item_level_3 .lesson_exam_post_item_ribbon span:before {
       background: darkred;
    }
    .lesson_exam_post_item_level_3 .lesson_exam_post_item_ribbon span:after {
       background: rgb(60, 0, 0);
    }
    .lesson_exam_post_item_teacher {
        float: right;
        margin-top: 5px;
    }
    .lesson_exam_post_item_teacher a {
        display: inline-block;
        margin-right: 5px;
        margin-top: 5px;
    }
    .lesson_exam_post_item_teacher img {
        float: right;
        width: 30px;
        border: 0;
        border-radius: 5px;
    }
    .lesson_exam_post_item_panel {
        float: right;
        margin-top: 5px;
        border: 1px solid #ccc;
        border-radius: 3px;
    }
    .lesson_exam_post_item_panel a {
        display: inline-block;
        margin: 0;
        padding: 1px 10px;
        background-color: #ddd;
        color: #555;
        box-shadow: 0 1px 0 rgba(0, 0, 0, .3),
              0 2px 2px -1px rgba(0, 0, 0, .5),
              0 1px 0 rgba(255, 255, 255, .3) inset;
        text-shadow: 0 1px 0 rgba(255,255,255, .9);
    }
    .lesson_exam_post_item_panel a:hover {
        background-color: #f3ecec;
    }
    .lesson_exam_post_item_panel a:first-child {
        border-right: 1px solid #f1eeee;
        border-top-left-radius: 3px;
        border-bottom-left-radius: 3px;
    }
    .lesson_exam_post_item_panel a:last-child {
        border-left: 1px solid #f1eeee;
        border-top-right-radius: 3px;
        border-bottom-right-radius: 3px;
    }
    .lesson_exam_post_item_content {
        text-align: justify;
        font-family: SVN-Georgia;
        font-size: 16px;
        margin-top: 30px;
    }
    .lesson_exam_post_item_content img {
        max-width: 100%;
    }
    .lesson_exam_post_choice_list {
        border: 1px solid #ccc;
        border-radius: 3px;
        margin-bottom: 10px;
    }
    label.lesson_exam_post_choice_item {
        padding: 0;
    }
    .lesson_exam_post_choice_item {
        padding: 10px 10px 10px 40px;
        border-bottom: 1px solid #ccc;
        position: relative;
    }
    .lesson_exam_post_choice_list .lesson_exam_post_choice_item:last-child {
        border: 0;
    }
    .lesson_exam_post_choice_item:hover, .lesson_exam_post_choice_label:hover {
        background-color: #B3E5A1;
    }
    .lesson_exam_post_choice_input {
        display: none;
    }
    .lesson_exam_post_choice_label {
        display: block;
        padding: 10px 10px 10px 40px;
        border-bottom: 1px solid #ccc;
    }
    .lesson_exam_post_choice_label_radio {
        background-image: url(img/icon_exam_post_circle.png);
        background-repeat: no-repeat;
        background-size: 20px 20px;
        background-position: 10px 50%;
    }
    .lesson_exam_post_choice_label_checkbox {
        background-image: url(img/icon_exam_post_square.png);
        background-repeat: no-repeat;
        background-size: 20px 20px;
        background-position: 10px 50%;
    }
    .lesson_exam_post_choice_input:checked + .lesson_exam_post_choice_label {
        background-color: #B3E5A1;
    }
    .lesson_exam_post_choice_input:checked + .lesson_exam_post_choice_label_radio {
        background-image: url(img/icon_exam_post_circle_check.png);
    }
    .lesson_exam_post_choice_input:checked + .lesson_exam_post_choice_label_checkbox {
        background-image: url(img/icon_exam_post_square_check.png);
    }
    .lesson_exam_post_choice_essay {
        margin: 0;
        padding: 10px;
        width: 100%;
        text-align: center;
        box-shadow: inset 2px 2px 4px rgba(0, 0, 0, 0.4);
    }
    .lesson_exam_post_choice_item img {
        border: 0;
        width: 20px;
        margin: 0;
        position: absolute;
        left: 10px;
        top: 50%;
        -ms-transform: translateY(-50%);
        transform: translateY(-50%);
    }
    .card-pin {
        width: 12px;
        height: 12px;
        background-color: #1d1d1d;
        position: absolute;
        top: 10px;
        border-radius: 50%;
        box-shadow: 0 0 0 2px #fff, 0 0 0 3px #1d1d1d;
        z-index: 1;
    }
    .lesson_exam_post_item .card-pin:nth-child(1) {
        left: 150px;
    }
    .lesson_exam_post_item .card-pin:nth-child(2) {
        right: 150px;
    }
    .card-pin:before, .card-pin:after {
        content: "";
        display: block;
        border-radius: 50%;
        position: absolute;
        transition: 0.15s ease-out;
    }
    .card-pin:before {
        width: 12px;
        height: 12px;
        background-color: #1d1d1d;
        border-radius: 50%;
        left: calc(50% - 6px);
        top: -54px;
    }
    .card-pin:after {
        width: 6px;
        background-color: #fff;
        border: 1px solid;
        border-radius: 99em;
        height: 60px;
        left: calc(50% - 3px);
        bottom: 3px;
    }

    /*Binh luan*/
    .faq {
        background: #F0F2F5;
        border: 1px solid #E2E7EF;
        -webkit-box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        -moz-box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        -moz-border-radius: 3px;
            -webkit-border-radius: 3px;
            border-radius: 3px;
        padding: 10px;
        margin: 20px 0;
    }
    .faq_form {
        margin-bottom: 10px;
    }
    .faq_list .faq_form {
        margin: 10px 0 0 0;
    }
    .faq_list .faq_form .faq_form_avatar {
        width: 40px;
    }
    .faq_list .faq_form .faq_form_area {
        margin-left: 50px;
    }
    .faq_form .faq_form_avatar {
        float: left;
        width: 50px;
        -moz-border-radius: 3px;
            -webkit-border-radius: 3px;
            border-radius: 3px;
    }
    .faq_form .faq_form_area {
        margin-left: 60px;
    }
    .faq_form .faq_form_area textarea {
        min-width: 100%;
        max-width: 100%;
        height: 40px;
		font-size: 13px;
        border: 1px solid #ccc;
        -moz-border-radius: 3px;
            -webkit-border-radius: 3px;
            border-radius: 3px;
    }
    .faq_form .faq_form_area textarea:focus {
        border: 1px solid #ddd;
    }
    .faq_form .faq_form_area .faq_form_submit {
        margin-top: 0;
        float: right;
    }
    .faq_form .faq_form_area .imageupload {
        display: none;
    }
    .faq_form .faq_form_area .faq_form_icon {
        float: left;
        margin-top: 0;
    }
    .faq_form .faq_form_area .faq_form_icon img {
        border: 0;
        height: 34px;
    }
    .faq_form .faq_form_area .post_photo {
        display: inline-block;
        padding: 2px;
        background: #ccc;
        border: 1px solid #ddd;
        -moz-border-radius: 3px;
            -webkit-border-radius: 3px;
            border-radius: 3px;
    }
    .faq_item {
        border-top: 1px solid #ccc;
        padding: 5px 0;
    }
    .faq_item .faq_item_avatar {
        float: left;
        width: 50px;
        -moz-border-radius: 3px;
            -webkit-border-radius: 3px;
            border-radius: 3px;
    }
    .faq_item .faq_item_area {
        margin-left: 60px;
    }
    .faq_item .faq_item_title span {
        display: inline-block;
        color: gray;
        margin-left: 15px;
    }
    .faq_item .faq_item_title b {
        color: blue;
		font: bold 16px OpenSansCondensed;
    }
    .faq_item .faq_item_content {
        margin-top: 5px;
        text-align: justify;
    }
    .faq_item .faq_item_photo {
        max-width: 100%;
		margin-top: 5px;
        border: 0;
    }

    /*Leader board*/
    .leaderboard {
        background: #f8f8f8;
        margin: 10px 0;
    }  
    .leaderboard .banner img{
        width: 100%;
        height: 240px;
        border-top-left-radius: 3px;
        border-top-right-radius: 3px;
        display: block;
    }
    .leaderboard .content {
        margin-top: 0;
        border: 1px solid #ccc;
        border-top: 0;
    }
    .leaderboard .content .home,
    .leaderboard .content .exam {
        padding: 5px 0;
    }  
    .leaderboard .content .item_container,
    .leaderboard .content .item_container .item{
        display: flex;
        align-items: center;
    }  
    .leaderboard .content .item_container{
        height: 60px;
        justify-content: space-between;
        margin: 0 10px;
        border-bottom: 1px solid #c5c5c5;
    }  
    .leaderboard .content .item_container:last-child{
        border-bottom: 0;
    }  
    .leaderboard .content .item_container .item_num {
        margin-right: 10px;
    }
    .leaderboard .content .item_container .item_img{
        margin-right: 10px;
        margin-left: 5px;
    }
    .leaderboard .content .item_container .item_num,
    .leaderboard .content .item_container .item_info p{
        font-size: 14px;
        margin: 0;
    }  
    .leaderboard .content .item_container .item_info span{
        font-size: 10px;
        color: gray;
    }  
    .leaderboard .tabs{
        margin-top: -11px;
        width: 100%;
        height: 40px;
        background: #fff;
        box-shadow: 0 2px 2px rgba(0,0,0,0.125);
    }  
    .leaderboard .tabs ul{
        height: 100%;
        display: flex;
        font-size: 14px;
        align-items: center;
        padding: 0 10px;
        list-style: none;
    }      
    .leaderboard .tabs ul li{
        width: 50%;
        text-align: center;
        position: relative;
        cursor: pointer;
        color: #fa5c43;
        font-weight: bold;
    }      
    .leaderboard .tabs ul li.active:before{
        content: "";
        position: absolute;
        bottom: -12px;
        left: 0;
        width: 100%;
        height: 2px;
        background: #fa5c43; 
    }

    .lesson_student_stat {
        padding: 0;
        border: 2px solid magenta;
    }
    .lesson_student_stat_header {
        background: magenta;
        color: #fff;
        padding: 10px 0;
        font-weight: bold;
    }
    .lesson_student_stat_rank {
        float: left;
        text-align: center;
        width: 70px;
    }
    .lesson_student_stat_score1, .lesson_student_stat_score2 {
        float: right;
        text-align: center;
    }
    .lesson_student_stat_item {
        padding: 10px 0;
        border-bottom: 1px solid #ccc;
        position: relative;
    }
    .lesson_student_stat_item:last-child {
        border: 0;
    }
    .lesson_student_stat_item:hover {
        background-color: lightcyan;
    }
    .lesson_student_stat_item .lesson_student_stat_rank {
        position: absolute;
        top: 50%;
        -ms-transform: translateY(-50%);
        transform: translateY(-50%);
    }
    .lesson_student_stat_item .lesson_student_stat_rank span {
        font-family: DDC;
        font-weight: bold;
        color: red;
        padding: 5px 10px;
        border: 2px solid navy;
        -webkit-box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        -moz-box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        -moz-border-radius: 50%;
            -webkit-border-radius: 50%;
            border-radius: 50%;
    }
    .lesson_student_stat_item .lesson_student_stat_score1, .lesson_student_stat_item .lesson_student_stat_score2 {
        text-align: center;
        font-weight: bold;
        position: absolute;
        top: 50%;
        -ms-transform: translateY(-50%);
        transform: translateY(-50%);
    }
    .lesson_student_stat_item .lesson_student_stat_name img {
        width: 40px;
        height: 40px;
        float: left;
        margin-right: 10px;
        border-radius: 3px;
    }
    .lesson_student_stat_item .lesson_student_stat_name span {
        color: gray;
    }
    .lesson_student_stat_top {
        margin: 0 10% -12px 10%;
        height: 200px;
    }
    .lesson_student_stat_top1, .lesson_student_stat_top2, .lesson_student_stat_top3 {
        float: left;
        width: 33.33%;
        height: 100%;
        text-align: center;
        position: relative;
    }
    .lesson_student_stat_top1 img, .lesson_student_stat_top2 img, .lesson_student_stat_top3 img {
        -webkit-box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        -moz-box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
    }
    .lesson_student_stat_top2 img {
        margin-top: 30px;
    }
    .lesson_student_stat_top3 img {
        margin-top: 60px;
    }
    .lesson_student_stat_top_column {
        position: absolute;
        bottom: 0;
        left: 5px;
        right: 5px;
        color: #fff;
        padding: 10px 10px 0 10px;
        font-weight: bold;
        font-family: DDC;
        font-size: 17px;
        line-height: 20px;
        text-shadow: #8b8a8a 1px 1px 1px;
    }
    .lesson_student_stat_top1_column {
        height: 130px;
        background-color: purple;
    }
    .lesson_student_stat_top2_column {
        height: 100px;
        background-color: navy;
    }
    .lesson_student_stat_top3_column {
        height: 70px;
        background-color: green;
    }

    .lesson_post_sidebar_class_list {
        margin-top: 10px;
    }
    .lesson_post_sidebar_class_list a {
        display: block;
        padding: 20px 0;
        margin-bottom: 10px;
        text-align: center;
        color: #fff;
        text-shadow: #8b8a8a 1px 1px 1px;
        border: 1px solid #ccc;
        border-radius: 5px;
    }
    .lesson_post_sidebar_class_list a:nth-child(5n+1) {
        background-color: #007957;
    }
    .lesson_post_sidebar_class_list a:nth-child(5n+2) {
        background-color: #CD0404;
    }
    .lesson_post_sidebar_class_list a:nth-child(5n+3) {
        background-color: royalblue;
    }
    .lesson_post_sidebar_class_list a:nth-child(5n+4) {
        background-color: #3A1078;
    }
    .lesson_post_sidebar_class_list a:nth-child(5n) {
        background-color: #FC7300;
    }
    .lesson_post_sidebar_class_list a:hover {
        background-color: magenta;
    }

    .lesson_test_type_list {
        margin-top: 10px;
    }
    .lesson_test_type_list a {
        display: block;
        padding: 20px 0;
        margin-bottom: 10px;
        text-align: center;
        color: #fff;
        text-shadow: #8b8a8a 1px 1px 1px;
        border: 1px solid #ccc;
        border-radius: 5px;
    }
    .lesson_test_type_list a:nth-child(5n+1) {
        background-color: #007957;
    }
    .lesson_test_type_list a:nth-child(5n+2) {
        background-color: #CD0404;
    }
    .lesson_test_type_list a:nth-child(5n+3) {
        background-color: #3A1078;
    }
    .lesson_test_type_list a:hover {
        background-color: magenta;
    }
    .lesson_test_timer {
        float: right;
        margin-right: 10px;
        color: #fff;
        font-weight: bold;
    }

    #lesson_interact_list {
        display: grid;
        grid-template-columns: 1fr 1fr;
        grid-template-rows: 1fr 1fr;
        grid-gap: 10px 10px;
    }
    .lesson_interact_app:hover {
        border-color: #000;
    }
    .lesson_interact_app img {
        width: 100%;
        height: 150px;
    }
    .lesson_interact_app h5 {
        font-weight: normal;
        font-style: italic;
    }

    /*Apps*/
    #apps_title {
        font-family: DDC;
        font-size: 25px;
        color: red;
        margin: 20px 0;
        text-align: center;
    }
    #apps_lottery_board {
        border: 2px solid red;
        margin-bottom: 20px;
        padding: 80px 0;
        text-align: center;
        text-transform: uppercase;
        background: url(img/apps_lottery_bg.jpg);
        background-repeat: no-repeat;
        background-size: cover;
        color: red;
        font-size: 38px;
        font-weight: bold;
        text-shadow: #8b8a8a 1px 1px 1px;
    }
    #lottery_button {
        padding: 10px 50px;
        font-size: 15px;
        cursor: pointer;
    }
    #apps_bag_board {
        background: url(img/apps_bag_bg.jpg);
        background-repeat: no-repeat;
        background-size: cover;
        -webkit-box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        -moz-box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        box-shadow: 1px 1px 1px rgba(0,0,0,0.3);
        height: 650px;
        padding-top: 220px;
    }
    #apps_bag_board_list {
        margin: 0 30px;
        font-family: SVN-Georgia;
        font-size: 16px;
        display: grid;
        grid-template-columns: repeat(5, 1fr);
        grid-template-rows: repeat(5, 1fr);
        grid-gap: 15px 10px;
        position: relative;
    }
    .apps_bag_board_item {
        display: block;
    }
    .apps_bag_board_item img {
        border: 0;
        width: 100%;
    }
    .lesson_exam_post_item {
        background: #fff;
    }
    #apps_bag_board_list .ex_box {
        display: none;
        position: absolute;
        top: -20px;
        right: 0;
        left: 0;
    }
    #apps_bag_board_list .ex_box h3 img {
        width: 12px;
    }
    .apps_bag_coin {
        background: url(img/apps_bag_coin.png);
        background-repeat: no-repeat;
        background-size: cover;
        display: inline-block;
        width: 20px;
        height: 20px;
        margin-right: 5px;
    }
    #bag_page_button {
        margin-top: 20px;
        width: 200px;
        font-size: 15px;
        cursor: pointer;
    }

@media screen and (min-width: 1000px) {
    #wrap {
        width: 100%;
        margin: -12px 0 0 0;
    }
    .container {
        width: 1000px;
        margin: 0 auto;
    }
    #lesson_post_sidebar {
        float: right;
        margin-top: 50px;
        width: 300px;
    }
    #lesson_post_sidebar_menu {
        margin: 10px 0;
    }
    #lesson_post_sidebar_menu a {
        display: block;
        border-radius: 5px;
        padding: 10px;
        font:bold 16px Aptima;
        color: #000;
        margin: 1px 0;
    }
    #lesson_post_sidebar_menu img {
        border: 0;
        width: 24px;
        margin-right: 10px;
        float: inline-start;
    }
    #lesson_post_sidebar_menu a:hover, #lesson_post_sidebar_menu a.current {
        background-color:rgb(251, 180, 251);
        color: #000;
    }
    #lesson_post_sidebar_cover {
        width: 100%;
        border: 0;
        border-radius: 3px;
        margin-bottom: 10px;
    }
    .lesson_post_sidebar_stat_title {
        margin: 0;
        padding: 0 0 5px 0;
        border-bottom: 1px solid #ccc;
        font-family: DDC;
        font-size: 20px;
        color: navy;
    }
    .lesson_post_sidebar_stat_list {
        margin: 0 0 10px 0;
    }
    .lesson_post_sidebar_stat_list a {
        display: block;
        padding: 10px 0;
        border-bottom: 1px solid #ccc;
    }
    .lesson_post_sidebar_stat_list a:last-child {
        border-bottom: 0;
    }
    .lesson_post_sidebar_stat_list a:hover {
        background: #FFF5EE;
    }
    .lesson_post_sidebar_stat_list a span {
        display: block;
    }
    .lesson_post_sidebar_stat_list a span.lesson_post_sidebar_stat_item_score {
        float: right;
        padding: 6px;
        border: 2px solid red;
        border-radius: 50%;
        color: red;
    }
    .lesson_post_sidebar_stat_list a span.lesson_post_sidebar_stat_item_class {
        color: black;
    }
    .lesson_post_sidebar_stat_list a span.lesson_post_sidebar_stat_item_time {
        color: gray;
    }
    #lesson_main {
        float: left;
        width: 650px;
    }
    .lesson_subject_item {
        width: 20%;
    }
    .lesson_subject_item img {
        height: 100px;
    }
    #form input[type=text], #form input[type=number], #form input[type=file], #form select, #form #tag {
		width: 100%;
        max-width: 100%;
	}
    #form textarea {
		width: 100%;
        max-width: 100%;
	}
	#form .text-editor {
		width: 100%;
        max-width: 100%;
	}

    .trello_list {
        -moz-column-count: 3;
        -webkit-column-count: 3;
        column-count: 3;
        column-gap: 10px;
    }
    .trello {
        break-inside: avoid-column;
    }

    #lesson_post_menu li a {
        padding: 8px 20px 10px 20px;
    }

    #lesson_post_menu_bottom_area {
        display: none;
    }
    
    .course {
        display: flex;
    }
    .course-info {
        float: left;
        width: 25%;
    }
    .course-progress {
        float: left;
        width: 63%;
    }

    .lesson_section_title {
        margin: 20px 0 10px 0;
    }
    .lesson_section_body {
        margin: 0;
    }
    .lesson_section_panel {
        margin: 20px 0 10px 0;
    }
    
    .lesson_student_stat_name {
        margin: 0 200px 0 70px;
    }
    .lesson_student_stat_score1, .lesson_student_stat_score2 {
        width: 100px;
    }
    .lesson_student_stat_score1 {
        right: 100px;
    }
    .lesson_student_stat_score2 {
        right: 0;
    }
    .lesson_test_type_list {
        display: grid;
        grid-template-columns: 1fr 1fr 1fr;
        grid-gap: 5px;
    }
	#lesson_main .lesson_post_sidebar_class_list {
        display: none;
    }
}

@media screen and (max-width: 999px) {
    #wrap {
        width: 100%;
        margin: -12px 0 0 0;
    }
    .container {
        margin: 10px;
    }
    .lesson_subject_item {
        width: 50%;
    }
    .lesson_subject_item img {
        height: 80px;
    }

    #lesson_post_sidebar {
        display: none;
    }
    #lesson_post_menu_bottom_area {
        margin-bottom: 20px;
    }
    #lesson_post_menu_bottom {
        list-style: none;
        width: 100%;
        margin: 0;
        padding: 0;
        display: grid;
    }
    #lesson_post_menu_bottom li {
        color: #fff;
        margin: 1px;
        border-radius: 3px;
        -webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
		box-shadow: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
		transition: all 0.3s cubic-bezier(.25,.8,.25,1);
    }
    #lesson_post_menu_bottom li#lesson_post_menu_bottom_home {
        background: blueviolet;
    }
    #lesson_post_menu_bottom li#lesson_post_menu_bottom_test {
        background: magenta;
    }
    #lesson_post_menu_bottom li#lesson_post_menu_bottom_exam {
        background: crimson;
    }
    #lesson_post_menu_bottom li#lesson_post_menu_bottom_stat {
        background: forestgreen;
    }
    #lesson_post_menu_bottom li#lesson_post_menu_bottom_interact {
        background: indigo;
    }
    #lesson_post_menu_bottom li#lesson_post_menu_bottom_score {
        background: indigo;
    }
    #lesson_post_menu_bottom li img {
        max-width: 40px;
        max-height: 40px;
        border: none;
        margin: 5px 0;
    }
    #lesson_post_menu_bottom li a {
        font: bold 14px Aptima;
        padding: 3px 0 5px 0;
        text-decoration:none;
        display: block;
        text-align: center;
        color: #ffffff;
    }
    #lesson_post_menu_bottom li a:hover, #lesson_post_menu_bottom li.active, #lesson_post_menu_bottom li.active:hover {
        color:#fff;
        background: navy;
        border-radius: 3px;
    }

    .course-info {
		width: 88%;
		float: none;
	}
	.course-info h2 {
		margin: 8px 0px;
	}
	.course-info a {
		margin-top: 10px;
	}
    .course-progress {
        float: none;
        width: 88%;
    }
    .course-progress button {
        margin-bottom: 20px;
    }
	.course-progress h5 {
		margin: 40px 0px 20px 0;
	}

    #form input[type=text], #form input[type=file], #form select, #form textarea, #form .text-editor, #form #tag {
		width: 100%;
        max-width: 100%;
	}

    .lesson_section_title {
        margin: 20px 0 10px 0;
    }
    .lesson_section_panel {
        margin: 20px 0 10px 0;
    }

    .timelines {
        margin-left: 2.5rem;
    }
    
    .lesson_student_stat_name {
        margin: 0 100px 0 70px;
    }
    .lesson_student_stat_score1, .lesson_student_stat_score2 {
        width: 50px;
    }
    .lesson_student_stat_score1 {
        right: 50px;
    }
    .lesson_student_stat_score2 {
        right: 0;
    }
}