Make scrollbar gutter stable

make the main scrollbar gutter stable so that the page doesn't jump around every time a modal is opened

Author: Abhinav5383

src/styles/main.css

@@ -166,6 +166,7 @@ select {
 \*------------------------------------*/
 html {
   color-scheme: dark;
+  scrollbar-gutter: stable;
 }
 
 body {