For example, <code><section></code> should be wrapped as inline.

<p>
    Highlight
    text with HTML <mark> tag
<p>

<ul class="list-unstyled f_social_icon">
    <li><a href="#"><i class="social_facebook"><i><a><li>
    <li><a href="#"><i class="social_twitter"><i><a><li>
    <li><a href="#"><i class="social_vimeo"><i><a><li>
    <li><a href="#"><i class="social_linkedin"><i><a><li>
<ul>

html {
  height: 100%;
}
a {
  text-decoration: none;
  transition: all 0.3s ease-in-out;
}
a:hover, a:focus {
  text-decoration: none;
  outline: none;
  color: #10b3d6;
}
body {
  line-height: 24px;
  font-size: 16px;
  height: 100%;
  font-family: "Roboto", sans-serif;
  font-weight: 400;
  color: #6b707f;
}

$(".img_popup").each(function () {
    $(".img_popup").magnificPopup({
        type: 'image',
        closeOnContentClick: true,
        closeBtnInside: false,
        fixedContentPos: true,
        removalDelay: 300,
        mainClass: 'mfp-no-margins mfp-with-zoom',
        image: {
            enabled: true,
            navigateByImgClick: true,
            preload: [0, 1]
        }
    });
})

function docly_setup() {
    load_theme_textdomain( 'kbDoc', get_template_directory() . '/languages' );

    // Add default posts and comments RSS feed links to head.
    add_theme_support( 'automatic-feed-links' );

    // Enable excerpt support for page
    add_post_type_support( 'page', 'excerpt' );

    // Enable WooCommerce Support
    add_theme_support( 'woocommerce' );

    add_theme_support( 'title-tag' );

    /*
     * Enable support for Post Thumbnails on posts and pages.
     *
     * @link https://developer.wordpress.org/themes/functionality/featured-images-post-thumbnails/
     */
    add_theme_support( 'post-thumbnails' );
    add_theme_support( 'post-formats', array( 'audio', 'video', 'quote', 'link' ) );

    // This theme uses wp_nav_menu() in one location.
    register_nav_menus( array(
        'main_menu'   => esc_html__( 'Main menu', 'kbDoc' ),
        'overlay_menu'   => esc_html__( 'Overlay menu', 'kbDoc' ),
    ));
}
add_action( 'after_setup_theme', 'docly_setup' );