set body font size to md

Author: pettinarip

src/@chakra-ui/gatsby-plugin/styles.ts

@@ -16,7 +16,7 @@ const styles = {
       // native Chakra semantic tokens
       bg: mode("white", "gray.700")(props),
       lineHeight: "base",
-      fontSize: ["sm", null, "md"],
+      fontSize: "md",
     },
     a: {
       color: "primary.base",