fix(qa2): responsive Latest-news/FAQ at tablet + muted-text contrast sweep

- Latest-news row and FAQ grid now go 3 -> 2 -> 1 columns (added a 1024px
  tablet step); .news-card drops its brittle fixed 405.33px width and fills a
  responsive grid cell. Fixes cramped 3-across cards on 769-1024px.
- Contrast: replace #98A2B3 text color (2.58:1 on white) with the palette
  muted #667085 (~4.8:1) across 13 CSS files (31 text-color uses; borders/
  backgrounds untouched, verified none on dark backgrounds).
- Re-stamped cache-bust (v=6770822f).

Note: the ~20px-looser header top-gap at 769-1024px is left as a minor,
lower-risk follow-up (would need a coordinated multi-page padding pass).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

404.html

@@ -25,7 +25,7 @@
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
     <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap" rel="stylesheet">
     <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.5.1/css/all.min.css" crossorigin="anonymous" referrerpolicy="no-referrer">
-    <link rel="stylesheet" href="/css/main.css?v=9ff60d7a">
+    <link rel="stylesheet" href="/css/main.css?v=6770822f">
 
     <link rel="icon" type="image/png" href="/favicon-96x96.png" sizes="96x96">
     <link rel="icon" type="image/svg+xml" href="/favicon.svg">
@@ -70,7 +70,7 @@
             </p>
         </div>
     </main>
-<link rel="stylesheet" href="/assistant.css?v=9ff60d7a">
-<script src="/assistant.js?v=9ff60d7a" defer></script>
+<link rel="stylesheet" href="/assistant.css?v=6770822f">
+<script src="/assistant.js?v=6770822f" defer></script>
 </body>
 </html>