无法在导航栏中水平对齐菜单项

import React from "react";
import {Navbar, Nav, NavItem} from "react-bootstrap";

class Header extends React.Component{
    render() {
        return (
            <Navbar inverse>
                <Navbar.Header>
                    <Navbar.Brand>
                        <a href="#brand">Tweelyze</a>
                    </Navbar.Brand>
                </Navbar.Header>
                <Nav>
                    <NavItem eventKey={1} href="#">Link1</NavItem>
                    <NavItem eventKey={2} href="#">Link2</NavItem>
                    <NavItem eventKey={2} href="#">Link2</NavItem>
                    <NavItem eventKey={2} href="#">Link2</NavItem>
                    <NavItem eventKey={2} href="#">Link2</NavItem>
                </Nav>
            </Navbar>
        );
    }
}

export default Header;

import React, { Component } from 'react';
import Header from "./NavigationBar"
class App extends Component {
  render() {
    return (
        <div><Header/></div>

    );
  }
}

export default App;

import React from 'react';
import ReactDOM from 'react-dom';
import App from './components/App';
import '../node_modules/bootstrap/dist/css/bootstrap.min.css';
ReactDOM.render(<App />, document.getElementById('root'));