transition animation not working in tailwindcss/react - reactjs

Question

I am a newbie learning React & Tailwind. I have a Navbar component which I have written like following,
const Navbar = () => {
const [showModal, setShowModal] = useState(false);
return (
<>
<nav className="flex justify-between items-center h-16 bg-white text-black relative shadow-md font-quicksand">
<Link to='/' className='pl-8'>Project</Link>
<div className="px-4 cursor-pointer md:hidden">
{/* <svg class="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg">
<path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 6h16M4 12h16M4 18h16"></path>
</svg> */}
<button
type="button"
className="bg-white rounded-md p-2 inline-flex items-center justify-center text-gray-400 hover:text-gray-500 hover:bg-gray-100 focus:outline-none focus:ring-2 focus:ring-inset focus:ring-indigo-500"
id="main-menu"
aria-haspopup="true"
onClick={() => setShowModal(true)}
>
<span className="sr-only">Open main menu</span>
<svg className="h-6 w-6" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor" aria-hidden="true">
<path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 6h16M4 12h16M4 18h16" />
</svg>
</button>
</div>
<div className="pr-8 md:block hidden">
<Link to='/' className='p-4 font-bold'>Home</Link>
<Link to='/menu' className='p-4 font-bold'>Menu</Link>
<Link to='/about' className='p-4 font-bold'>About</Link>
<Link to='/contact' className='p-4 font-bold'>Contact</Link>
<Link to='/login' className="p-4 font-bold text-indigo-600 hover:text-indigo-500" role="menuitem">Log in</Link>
<Link to='/register' className="p-4 font-bold text-indigo-600 hover:text-indigo-500" role="menuitem">Register</Link>
</div>
</nav>
{showModal ? (
<div className="absolute top-0 inset-x-0 p-2 transition duration-500 ease-in-out transform origin-top-right md:hidden">
<div className="rounded-lg shadow-md bg-white ring-1 ring-black ring-opacity-5 overflow-hidden">
<div className="px-5 pt-4 flex items-center justify-between">
<div className="-mr-2">
<button
type="button"
className="bg-white rounded-md p-2 inline-flex items-center justify-center text-gray-400 hover:text-gray-500 hover:bg-gray-100 focus:outline-none focus:ring-2 focus:ring-inset focus:ring-indigo-500"
onClick={() => setShowModal(false)}
>
<span className="sr-only">Close main menu</span>
<svg className="h-6 w-6" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor" aria-hidden="true">
<path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M6 18L18 6M6 6l12 12" />
</svg>
</button>
</div>
</div>
<div role="menu" aria-orientation="vertical" aria-labelledby="main-menu">
<div className="px-2 pt-2 pb-3 space-y-1" role="none">
<Link to='/' className="block px-3 py-2 rounded-md text-base font-medium text-gray-700 hover:text-gray-900 hover:bg-gray-50" role="menuitem">Home</Link>
<Link to='/menu' className="block px-3 py-2 rounded-md text-base font-medium text-gray-700 hover:text-gray-900 hover:bg-gray-50" role="menuitem">Menu</Link>
<Link to='/about' className="block px-3 py-2 rounded-md text-base font-medium text-gray-700 hover:text-gray-900 hover:bg-gray-50" role="menuitem">About</Link>
<Link to='/contact' className="block px-3 py-2 rounded-md text-base font-medium text-gray-700 hover:text-gray-900 hover:bg-gray-50" role="menuitem">Contact</Link>
</div>
<div role="none">
<Link to='/login' className="block w-full px-5 py-3 text-center font-medium text-indigo-600 bg-gray-50 hover:bg-gray-100" role="menuitem">
Log in
</Link>
</div>
<div role="none">
<Link to='/register' className="block w-full px-5 py-3 text-center font-medium text-indigo-600 bg-gray-50 hover:bg-gray-100" role="menuitem">
Register
</Link>
</div>
</div>
</div>
</div>
) : null}
</>
)
}
As you can see that when the screen got smaller the hamburger menu button will appear and when I click on that button it opens a modal with all the header components (The modal code copied from tailwind official components Hero components).
The problem is when that modal appears tailwind transition animation suppose to happen but it is not working. What am i doing wrong here?? Do i have to use the react hook useEffect somehow to make this work??
Any kind of answer would be appreciated.