modal-menu.js

...
render() {
    const { items, openedMenu, onClose } = this.props;

    return (
      <Transition in={openedMenu} timeout={openedMenu ? 0 : 300}>
        {(status) => (

          <nav 
            id="menu-mobile"
            aria-labelledby="menu-hamburger"
            role="menu"
            className={`
                ${styles.container}
                ${(status === 'entered') ? styles.showContainer : ''}
            `}
           >

            <button 
                className={`${styles.closeButton}`}
                onClick={onClose}
            >
                Close menu
            </button>

            <ul className={styles.list}>
              {items.map((item, i) =>
                <li 
                    className={`
                        ${styles.item}
                        ${(status === 'entered') ? styles.showItem : ''}
                    `}
                    key={item.title}
                >
                  <Link
                    to={item.path}
                    className={`
                        ${typography.display2}
                        ${styles.link}
                    `}
                    >
                        { item.title }
                    </Link>
                </li>
               )}
            </ul>

          </nav>
        )}
      </Transition>
    );
}
...