docs: add introduction and features doc (#320)

Author: Timeless0911

README.md

@@ -12,9 +12,15 @@
   <a href="https://github.com/web-infra-dev/rslib/blob/main/LICENSE"><img src="https://img.shields.io/badge/License-MIT-blue.svg?style=flat-square&colorA=564341&colorB=F8F5FF" alt="license" /></a>
 </p>
 
-Rslib is a library build tool powered by [Rsbuild](https://rsbuild.dev). It allows library developers to leverage the knowledge and ecosystem of webpack and Rspack. Rslib is built on top of Rsbuild's excellent configurations and plugins, providing optimal ESM and CJS output.
+Rslib is a library build tool that leverages the well-designed configurations and plugins of [Rsbuild](https://rsbuild.dev), empowering library developers to take advantage of the extensive knowledge and ecosystem of webpack and Rspack.
 
-Rslib provides out-of-the-box configurations for library development, including compilation of TypeScript, JSX, Sass, Less, CSS Modules, and Wasm. It supports bundleless output, DTS generation (including isolated declarations), Module Federation, assets compression, type checking, PostCSS, and Lightning CSS.
+Rslib provides a comprehensive set of build features for library development, including:
+
+- **Compilation of diverse languages**: TypeScript, JSX, Sass, Less, CSS Modules, Wasm, and more.
+- **Flexible build modes**: Bundle and bundleless options to meet varying needs.
+- **Multiple output formats**: ESM, CJS, and UMD for maximum compatibility.
+- **Declaration file generation**: Including isolated declarations.
+- **Advanced features**: Module Federation, asset compression, PostCSS, Lightning CSS, and more.
 
 ## ✨ Why Rslib?
 

website/docs/en/guide/start/index.mdx

@@ -1,12 +1,30 @@
 # Introduction
 
+Rslib is a library build tool that leverages the well-designed configurations and plugins of [Rsbuild](https://rsbuild.dev), empowering library developers to take advantage of the extensive knowledge and ecosystem of webpack and Rspack.
+
+Rslib provides a comprehensive set of build features for library development, including:
+
+- **Compilation of diverse languages**: TypeScript, JSX, Sass, Less, CSS Modules, Wasm, and more.
+- **Flexible build modes**: Bundle and bundleless options to meet varying needs.
+- **Multiple output formats**: ESM, CJS, and UMD for maximum compatibility.
+- **Declaration file generation**: Including isolated declarations.
+- **Advanced features**: Module Federation, asset compression, PostCSS, Lightning CSS, and more.
+
 ## 🔥 Features
 
+Rslib has the following features:
+
+- **Easy to Configure**: Rslib aims to simplify library development by offering ready-to-use build capabilities, enabling developers to kickstart their library projects with minimal configuration.
+
+- **Performance Oriented**: Rslib integrates high-performance Rust-based tools from the community, including Rspack, SWC and Lightning CSS, to deliver first-class build speed and development experience.
+
+- **Plugin Ecosystem**: Powered by Rsbuild, Rslib benefits from a lightweight plugin system and a collection of high-quality official plugins. Furthermore, Rsbuild's compatibility with most webpack plugins and all Rspack plugins allows library developers to seamlessly integrate existing community or in-house plugins into their library projects.
+
 ## 🎯 Ecosystem
 
 Rslib is implemented based on Rsbuild and fully reuses the capabilities and ecology of Rsbuild.
 
-The following diagram illustrates the relationship between Rsbuild and other tools in the ecosystem:
+The following diagram illustrates the relationship between Rslib and other tools in the ecosystem:
 
 ![Rspack stack layers](https://assets.rspack.dev/rsbuild/assets/rspack-stack-layers.png)