Highlight side-by-side demo site in README

Emphasize the demo site link in the README.

Author: ShreckYe

README.md

@@ -17,7 +17,7 @@ The Compose HTML / JS DOM source is mainly based on [Kobweb Silk](https://github
 
 ## References and limitations
 
-Complete visual consistency across different platforms is not guaranteed. See [the side-by-side demo site](https://huanshankeji.github.io/compose-multiplatform-html-unified/demo/) for the visual effects and their differences.
+Complete visual consistency across different platforms is not guaranteed. See [the **side-by-side demo** site](https://huanshankeji.github.io/compose-multiplatform-html-unified/demo/) for the visual effects and their differences.
 
 This project is still in development and has not reached a stable state. Some APIs are subject to change and there is no detailed documentation yet. Check out [the demo project source](demo) on how to use the components in addition to the sections below.