ui+content: zoom the backdrop + de-dupe blog titles

- Backdrop image scaled 168% → 215% so the Bat-Computer board reads bigger
  and more immersive, with more room for the scroll-pan.
- Retitle the least-privilege post "The most secure credential is the one
  you never mount" → "Every pod holds a key to a door it never opens" so it
  no longer mirrors the "...inbound port is the one you never open" post.

src/styles/global.css

@@ -371,8 +371,10 @@ svg {
   position: absolute;
   top: 50%;
   left: 50%;
-  width: 168%;
-  height: 168%;
+  /* Zoomed in — larger than viewport so the board reads big/immersive and the
+     scroll-pan has room to travel. */
+  width: 215%;
+  height: 215%;
   object-fit: cover;
   transform: translate(-50%, -50%);
   will-change: transform;