/* カーソルでなぞった文字反転 */
function custom_admin_selection_style() {
    echo '<style>
        ::selection {
            background: #3399ff !important;
            color: white !important;
        }
    </style>';
}
add_action('admin_head', 'custom_admin_selection_style');<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /usr/home/hbv10033b5hj/html/blog/wp-content/themes/fcblog/functions.php:42) in <b>/usr/home/hbv10033b5hj/html/blog/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1775</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /usr/home/hbv10033b5hj/html/blog/wp-content/themes/fcblog/functions.php:42) in <b>/usr/home/hbv10033b5hj/html/blog/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1775</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /usr/home/hbv10033b5hj/html/blog/wp-content/themes/fcblog/functions.php:42) in <b>/usr/home/hbv10033b5hj/html/blog/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1775</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /usr/home/hbv10033b5hj/html/blog/wp-content/themes/fcblog/functions.php:42) in <b>/usr/home/hbv10033b5hj/html/blog/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1775</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /usr/home/hbv10033b5hj/html/blog/wp-content/themes/fcblog/functions.php:42) in <b>/usr/home/hbv10033b5hj/html/blog/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1775</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /usr/home/hbv10033b5hj/html/blog/wp-content/themes/fcblog/functions.php:42) in <b>/usr/home/hbv10033b5hj/html/blog/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1775</b><br />
<br />
<b>Warning</b>:  Cannot modify header information - headers already sent by (output started at /usr/home/hbv10033b5hj/html/blog/wp-content/themes/fcblog/functions.php:42) in <b>/usr/home/hbv10033b5hj/html/blog/wp-includes/rest-api/class-wp-rest-server.php</b> on line <b>1775</b><br />
{"id":56,"count":2,"description":"","link":"https:\/\/www.flatcord.co.jp\/blog\/category\/ces","name":"CES","slug":"ces","taxonomy":"category","parent":0,"meta":[],"_links":{"self":[{"href":"https:\/\/www.flatcord.co.jp\/blog\/wp-json\/wp\/v2\/categories\/56"}],"collection":[{"href":"https:\/\/www.flatcord.co.jp\/blog\/wp-json\/wp\/v2\/categories"}],"about":[{"href":"https:\/\/www.flatcord.co.jp\/blog\/wp-json\/wp\/v2\/taxonomies\/category"}],"wp:post_type":[{"href":"https:\/\/www.flatcord.co.jp\/blog\/wp-json\/wp\/v2\/posts?categories=56"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}