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Code snippet for center the header nav menu
HTML
/* code for menu */
.header__active-menu-item { text-decoration: none; }
.header__menu-item:hover span { text-decoration: none; }
/* code for Sub menu */
details[open]>.header__menu-item { text-decoration: none; }
.header__submenu .header__menu-item:hover { text-decoration-line: none; }