Accessibility: incremental header tag jumps

Author: barronbytes

index.html

@@ -30,7 +30,7 @@
     <main id="home-main" class="grid" tabindex="-1">
         <div id="home-content" class="flex-y">
             <h1 class="cta-header">Spend seconds to <span class="underline-yellow">create lesson plans</span>.</h1>
-            <h3 class="cta-subheader"><span class="underline-yellow">Enter your learning target</span>, and we'll do the rest.</h3>
+            <h2 class="cta-subheader"><span class="underline-yellow">Enter your learning target</span>, and we'll do the rest.</h2>
             <form action="lesson-inputs.html" method="GET" aria-label="Enter learning target">
                 <label for="learning-target" class="sr-only">Learning Target</label>
                 <input