Update challenge general description

Author: laike9m

templates/challenge.html

@@ -135,7 +135,7 @@
         align-items: center;
         gap: 0;
       }
-      
+
       .challenge-main .codemirror-container,
       .challenge-main .tests-result-container {
         width: 100%;
@@ -175,13 +175,13 @@
           {%include 'components/badge.html' with context %}
         </div>
         <p class="challenge-header__exerpt">
-        Complete code following the instructions below, so that there are no type errors
-        throughout the test code except for those lines followed by a <code># expect-type-error</code> comment.
-        You don't need to implement the function, just add type annotations.
-        Hit the "Run" button to see result.
+        Complete code on the left side following the instructions.<br>
+        Right side is test code, lines followed by <code># expect-type-error</code>
+        should fail type check, others should pass.<br>
+        Hit the "▶️ Run" button to see result.
       </p>
       </div>
-      
+
       <div class="challenge-main">
         <!-- Code Editor Area -->
       <div class="codemirror-container">
@@ -262,4 +262,4 @@
     checkWidth();  // Check the width initially
     window.addEventListener('resize', checkWidth);
   </script>
-{% endblock %}
+{% endblock %}