docs: prototype interactive Sandboxes diagram

assets/css/style.css

@@ -42,6 +42,7 @@
 @import "syntax-dark.css";
 @import "syntax-light.css";
 @import "components.css";
+@import "interactive-diagram.css";
 @import "highlight-github-dark.css";
 
 @variant dark (&:where(.dark, .dark *));