Fix difficulty progression and batch processing issues

- Fix inconsistent pass rate calculation that made Level 11 easier than Level 10
- Show pass requirements at all levels for better user feedback
- Add timeout handling to batch processing to prevent abort errors
- Improve error handling with specific abort error messaging

src/aiService.js

@@ -298,6 +298,10 @@ Passage: "${passage}"`
     }
 
     try {
+      // Add timeout controller to prevent aborted operations
+      const controller = new AbortController();
+      const timeoutId = setTimeout(() => controller.abort(), 15000); // 15 second timeout
+      
       const response = await fetch(this.apiUrl, {
         method: 'POST',
         headers: {
@@ -306,6 +310,7 @@ Passage: "${passage}"`
           'HTTP-Referer': window.location.origin,
           'X-Title': 'Cloze Reader'
         },
+        signal: controller.signal,
         body: JSON.stringify({
           model: this.model,
           messages: [{
@@ -349,6 +354,9 @@ Return as JSON: {"passage1": {...}, "passage2": {...}}`
         })
       });
 
+      // Clear timeout on successful response
+      clearTimeout(timeoutId);
+
       if (!response.ok) {
         throw new Error(`API request failed: ${response.status}`);
       }
@@ -502,6 +510,17 @@ Return as JSON: {"passage1": {...}, "passage2": {...}}`
         }
       }
     } catch (error) {
+      // Clear timeout in error case too
+      if (typeof timeoutId !== 'undefined') {
+        clearTimeout(timeoutId);
+      }
+      
+      // Handle specific abort error
+      if (error.name === 'AbortError') {
+        console.error('Batch processing timed out after 15 seconds');
+        throw new Error('Request timed out - falling back to sequential processing');
+      }
+      
       console.error('Error processing passages:', error);
       throw error;
     }

src/app.js

@@ -157,10 +157,8 @@ class App {
   displayResults(results) {
     let message = `Score: ${results.correct}/${results.total} (${results.percentage}%)`;
     
-    // Only show "Required" information at Level 3 and above
-    if (this.game.currentLevel >= 3) {
-      message += ` - Required: ${results.requiredCorrect}/${results.total}`;
-    }
+    // Show "Required" information at all levels for consistency
+    message += ` - Required: ${results.requiredCorrect}/${results.total}`;
     
     if (results.passed) {
       // Check if this completes the requirements for level advancement
@@ -172,11 +170,7 @@ class App {
       }
       this.elements.result.className = 'mt-4 text-center font-semibold text-green-600';
     } else {
-      if (this.game.currentLevel >= 3) {
-        message += ` - Need ${results.requiredCorrect} correct to advance. Keep practicing! 💪`;
-      } else {
-        message += ` - Keep practicing! 💪`;
-      }
+      message += ` - Need ${results.requiredCorrect} correct to advance. Keep practicing! 💪`;
       this.elements.result.className = 'mt-4 text-center font-semibold text-red-600';
     }
     

src/clozeGameEngine.js

@@ -805,14 +805,14 @@ class ClozeGame {
   // Calculate required correct answers based on total blanks
   calculateRequiredCorrect(totalBlanks) {
     if (totalBlanks === 1) {
-      // Level 1: Must get the single word correct
+      // 1 blank: Must get it correct
       return 1;
-    } else if (totalBlanks % 2 === 1) {
-      // Odd number of blanks (3, 5, etc.): require all but one
-      return totalBlanks - 1;
+    } else if (totalBlanks === 2) {
+      // 2 blanks: Need both correct (keeps current Level 6-10 difficulty)
+      return 2;
     } else {
-      // Even number of blanks: require all correct
-      return totalBlanks;
+      // 3+ blanks: Need all but one (fixes Level 11+ to be harder than Level 10)
+      return totalBlanks - 1;
     }
   }