Hero: full-bleed ambient loop behind nav + left-edge blend (match reference)

Stop boxing the loop. Pull .hero-media out of the content grid to a direct child
of .hero, absolutely positioned to bleed off the right edge and up behind the
frosted nav. Dissolve its left edge into the paper with a gradient mask-image and
warm it with a subtle paper/multiply overlay so it reads as cream, not stark
white — matching how Manus meshed it in. Mobile = full-width strip with a
bottom fade.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

index.html

@@ -87,10 +87,10 @@
       </div>
       <p class="call">or call <a class="tel" data-p1="778" data-p2="985" data-p3="6736" href="#contact">778&#8209;985&#8209;OPEN (6736)</a></p>
     </div>
+    </div>
     <div class="hero-media" aria-hidden="true">
       <video class="hero-video" muted loop playsinline preload="none" data-src="assets/media/hero-loop.webm"></video>
     </div>
-    </div>
   </section>
 
   <section class="band dark statement" data-bg="dark" id="problem">