thu frontend summer course project.
use npm install to install dependencies. We use react, react-dom, next.js and use-immer.
dev: npm run dev
_app.js: 入口文件，可以在此处放置全局context
_document.js: 修改<head>, <body>等被隐藏的tag，第三方css或js在此处引入
components: 部件存放处
contexts: 主要用于跨页面的信息传递，慎用
public\images: 图片等资源存放处
pages: 页面存放处
styles: css文件存放处，对于每个部件或页面，建立形如<name>.module.css的css文件使用
useState: declare with form of [state, setState]. Never modify state directly.
useEffect: async function called after rendering.
useRoute: switch pages. Pass props by query, use JSON.stringify with object. Use useEffett with route.query to get data after routing.
useContext: to send props deeply. Use it carefully.
https://yqnn.github.io/svg-path-editor/ https://www.w3schools.com/howto/howto_css_switch.asp