themes/fukasawa/components/MenuItemDrop.js

import Link from 'next/link'
import { useState } from 'react'

export const MenuItemDrop = ({ link }) => {
  const [show, changeShow] = useState(false)
  const hasSubMenu = link?.subMenus?.length > 0

  return <li onMouseOver={() => changeShow(true)} onMouseOut={() => changeShow(false)}
        className='relative py-1 duration-500 justify-between text-gray-500 dark:text-gray-300 hover:text-black hover:underline cursor-pointer flex flex-nowrap items-center '>

        {!hasSubMenu &&
            <Link href={link?.to} target={link?.to?.indexOf('http') === 0 ? '_blank' : '_self'} className='w-full my-auto items-center justify-between flex ' >
                <div><div className={`${link.icon} text-center w-4 mr-2`} />{link.name}</div>
                {link.slot}
            </Link>}

        {hasSubMenu &&
            <div className='w-full my-auto items-center justify-between flex '>
                <div><div className={`${link.icon} text-center w-4 mr-2`} />{link.name}</div>
                {link.slot}
                {hasSubMenu && <div className='text-right'><i className={`px-2 fas fa-chevron-right duration-500 transition-all ${show ? ' rotate-180' : ''}`}></i></div>}
            </div>}

        {/* 子菜单 */}
        {hasSubMenu && <ul className={`${show ? 'visible opacity-100 left-52' : 'invisible opacity-0 left-40'} z-20 py-1 absolute right-0 top-0 w-full border-gray-100  bg-white  dark:bg-black dark:border-gray-800 transition-all duration-300 drop-shadow-lg `}>
            {link?.subMenus?.map((sLink, index) => {
              return <li key={index}>
                    <Link href={sLink.to} target={link?.to?.indexOf('http') === 0 ? '_blank' : '_self'} className='my-auto py-1 px-2 items-center justify-start flex text-gray-500 dark:text-gray-300 hover:text-black  hover:bg-gray-50 dark:hover:bg-gray-900 tracking-widest transition-all duration-200 dark:border-gray-800 '>
                        {sLink.icon && <i className={`${sLink.icon} w-4 text-center `} />}
                        <div className={'ml-2 whitespace-nowrap'}>{sLink.name}</div>
                        {sLink.slot}
                    </Link>
                </li>
            })}
        </ul>}

    </li>
}