update: create new docs

docs/Web/helloworld/first_page.md

@@ -0,0 +1,24 @@
+---
+sidebar_position: 1
+---
+
+# 第一个页面（hello world）
+
+```html title="examples/hello-world/index.html"
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Document</title>
+  </head>
+  <body>
+    <div>hello world</div>
+  </body>
+</html>
+```
+
+将文件在浏览器中打开，你将会看到 `hello world` 字样
+
+![预览效果](./hello_world.png)