我是Vue的新手，有一些nodejs后端经验。我遇到了问题，不断得到一个错误：
“Uncaught TypeError：VueRouter is not a constructor”.这是我的代码（app.js）：

const routes=[
{ path:'/home', component: home },
{ path:'/zaposlenik', component: zaposlenik },
{path:'/department', component: department }
]


const route = new VueRouter({
routes
})

const app= new Vue({
router
}).$mount('#app')

字符串
我的department.js看起来像：

const department={template: '<h1>Ovo je odsjek</h1>'}

型
当然，我还有这个：

<nav class="navbar navbar-expand-sm bg-light navbar-dark">
        <ul class="navbar-nav">
            <li class="nav-item m-1">
                <router-link class="btn btn-light btn-outline-primary" to="/home">Home</router-link>
            </li>

            <li class="nav-item m-1">
                <router-link class="btn btn-light btn-outline-primary" to="/department">Odjel</router-link>
            </li>

            <li class="nav-item m-1">
                <router-link class="btn btn-light btn-outline-primary" to="/zaposlenik">Zaposlenik</router-link>
            </li>
        </ul>

    </nav>

    <router-view></router-view>

</div>

<script src="variables.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/axios/0.26.0/axios.min.js"></script>

<script src="https://unpkg.com/vue@3"></script>
<script src="https://unpkg.com/vue-router@4"></script>
<script src="home.js"></script>
<script src="department.js"></script>
<script src="zaposlenik.js"></script>
<script src="app.js"></script>

型
你能帮帮我吗？
先谢谢你了，
Vinko