tutorial: Update css in App.svelte in a and b examples to make display more readable (sveltejs#880)

* Update App.svelte

made the fonts larger and heavier for improved readability of the example

* Update App.svelte

made the fonts larger and heavier for improved readability of the example

---------

Co-authored-by: Tee Ming <chewteeming01@gmail.com>

Author: laelhalawani

apps/svelte.dev/content/tutorial/01-svelte/04-logic/04-each-blocks/+assets/app-a/src/lib/App.svelte

@@ -36,6 +36,8 @@
 
 <style>
 	h1 {
+		font-size: 2rem;
+		font-weight: 700;
 		transition: color 0.2s;
 	}
 
@@ -53,6 +55,9 @@
 		transform: translate(-2px,-2px);
 		filter: drop-shadow(2px 2px 3px rgba(0,0,0,0.2));
 		transition: all 0.1s;
+		color: black;
+		font-weight: 700;
+		font-size: 2rem;
 	}
 
 	button[aria-current="true"] {

apps/svelte.dev/content/tutorial/01-svelte/04-logic/04-each-blocks/+assets/app-b/src/lib/App.svelte

@@ -19,6 +19,8 @@
 <style>
 	h1 {
 		transition: color 0.2s;
+		font-size: 2rem;
+		font-weight: 700;
 	}
 
 	div {
@@ -35,6 +37,9 @@
 		transform: translate(-2px,-2px);
 		filter: drop-shadow(2px 2px 3px rgba(0,0,0,0.2));
 		transition: all 0.1s;
+		color: black;
+		font-weight: 700;
+		font-size: 2rem;
 	}
 
 	button[aria-current="true"] {