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doc/introduction.md

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+@mainpage Introduction
+@tableofcontents
+
+<img src="https://github.com/ArthurSonzogni/FTXUI/assets/4759106/6925b6da-0a7e-49d9-883c-c890e1f36007" alt="Demo image"></img>
+
+**FTXUI** is simple cross-platform C++ library for terminal based user interfaces!
+
+# Feature
+ * Functional style. Inspired by
+   [1](https://hackernoon.com/building-reactive-terminal-interfaces-in-c-d392ce34e649?gi=d9fb9ce35901)
+   and [React](https://reactjs.org/)
+ * No dependencies
+ * **Cross platform**.
+ * Simple and elegant syntax (in my opinion)
+ * Keyboard & mouse navigation.
+ * Support for [UTF8](https://en.wikipedia.org/wiki/UTF-8) and [fullwidth chars](https://en.wikipedia.org/wiki/Halfwidth_and_fullwidth_forms) (→ 测试)
+ * Support for animations. [Demo 1](https://arthursonzogni.github.io/FTXUI/examples/?file=component/menu_underline_animated_gallery), [Demo 2](https://arthursonzogni.github.io/FTXUI/examples/?file=component/button_style)
+ * Support for drawing. [Demo](https://arthursonzogni.github.io/FTXUI/examples/?file=component/canvas_animated)
+ * Learn by [examples](#documentation), and [tutorials](#documentation)
+ * Multiple build system and packages: 
+ * Good practices: documentation, tests, fuzzers, performance tests, automated CI, automated packaging, etc...
+
+# Example
+
+```cpp
+#include <ftxui/dom/elements.hpp>
+#include <ftxui/screen/screen.hpp>
+#include <iostream>
+
+int main() {
+  using namespace ftxui;
+
+  // Create a simple document with three text elements.
+  Element document = hbox({
+    text("left")   | border,
+    text("middle") | border | flex,
+    text("right")  | border,
+  });
+
+  // Create a screen with full width and height fitting the document.
+  auto screen = Screen::Create(
+    Dimension::Full(),       // Width
+    Dimension::Fit(document) // Height
+  );
+
+  // Render the document onto the screen.
+  Render(screen, document);
+
+  // Print the screen to the console.
+  screen.Print();
+}
+```
+
+Expected output:
+
+```
+┌────┐┌────────────────────────────────────┐┌─────┐
+│left││middle                              ││right│
+└────┘└────────────────────────────────────┘└─────┘
+```
+
+# Supported Platforms
+
+- Linux
+- MacOS
+- Windows
+- WebAssembly
+
+<div class="section_buttons">
+ 
+|                                  Next |
+|--------------------------------------:|
+| [Getting Started](getting-started.html) |
+ 
+</div>