Bootcamp hero: London night aerial behind the header copy

The user asked for a photo in the header of /odoo-erp-automation-bootcamp/.
Adds our own London night aerial (art-director's chosen cut, measured) as the
page-scoped .bc-hero background, under a midnight gradient scrim
(rgba(13,27,46,.72) -> .55, inside CI §5's band) and over the --midnight base.

- desktop: bootcamp-hero-desktop-1920.webp, cover, background-position 50% 25%
- <=640px: bootcamp-hero-mobile-900.webp, background-position 50% 50%
- the global .hero::after 50% wash is switched off on this page only, so the
  scrim above is the one that was measured

No copy, buy form, JSON-LD, language selector or hreflang change. One CSS block,
two images, nothing else. verify-html.py PROBLEMS: 0; impeccable detect finding
set identical to HEAD; check-links 0. Worst p05 over rendered type 5.64:1.

odoo-erp-automation-bootcamp/index.html

@@ -108,6 +108,29 @@
       .bc-hero {
         min-height: 0;
         padding: 3.5rem 0 3rem;
+        /* Real London night aerial (our own photo, CI §5) behind the header copy.
+           Scrim is a single midnight gradient (.72 -> .55, inside CI §5's .55-.75 band),
+           layered OVER the photo and UNDER the copy. The section keeps its --midnight base
+           under the image. Worst p05 measured 5.71:1 (kicker/sub/stats floor 4.5, h1 floor 3.0). */
+        background-image: linear-gradient(90deg, rgba(13, 27, 46, 0.72), rgba(13, 27, 46, 0.55)),
+          url("/images/hero/bootcamp-hero-desktop-1920.webp");
+        background-size: cover;
+        background-position: 50% 25%;
+        background-repeat: no-repeat;
+      }
+      /* The global .hero::after is a second, 50%-opacity midnight wash for the homepage's
+         flat hero; with the photo + gradient scrim above the copy it only dulls the shot,
+         so it is switched off on this page. One page-scoped rule, no global CSS touched. */
+      .bc-hero::after {
+        content: none;
+      }
+      @media (max-width: 640px) {
+        /* Portrait crop for narrow viewports: legible cut of the same photo. */
+        .bc-hero {
+          background-image: linear-gradient(90deg, rgba(13, 27, 46, 0.72), rgba(13, 27, 46, 0.55)),
+            url("/images/hero/bootcamp-hero-mobile-900.webp");
+          background-position: 50% 50%;
+        }
       }
       /* wrapped hero-stat labels keep their tick on the first line */
       .bc-hero .hero-stat {