Update README.md

Author: nimoooos

README.md

@@ -11,7 +11,7 @@ Algebraic move notations are not supported at this time.
 `quit` to concede.
 
 ## Demo
-[Demo Video](./media/Demo.mp4)
+[Demo Video](https://soomin-song-mssa-pcad17.github.io/Mini-Project---Console-Chess/)
 ![Screenshot1](./media/Screenshot1.png)
 ![Screenshot2](./media/Screenshot2.png)
 ![Screenshot3](./media/Screenshot3.png)