Add mobile tape shadows and center bank heading

docs/implementation.md

@@ -4,7 +4,7 @@ The supplied 1200 × 900 PDF and its IDML source define the desktop composition.
 
 CSS lives in `assets/styles.css`; all colors are CSS custom properties. Its link in `index.html` carries a content-hash query parameter; update that value when the CSS changes to avoid stale browser caches. Layout scales with the design above 1024 px. At smaller sizes the type becomes larger and wraps; at 600 px the bank and PayPal details stack in their original reading order. The mobile background separates the supplied tape from the photograph so that it remains above the logo while the photo fills a tall page. `assets/app.mjs` only enhances the IBAN with clipboard support and an accessible selection fallback. Contact and payment links work without JavaScript.
 
-At 1024 px and below, both decorative images are ordinary `body` backgrounds. The desktop pseudo-elements and isolated stacking context are disabled, leaving mobile touch scrolling to the document without separate decorative layers.
+At 1024 px and below, both decorative images are ordinary `body` backgrounds. The tape SVG applies the original shadow settings to each strip, including their overlap. Its 270 pt view box leaves room for the shadow without moving or scaling the artwork. The desktop pseudo-elements and isolated stacking context are disabled, leaving mobile touch scrolling to the document without separate decorative layers. At 600 px and below, the Kontodaten heading is centered above the bank details.
 
 ## Preview and deployment
 

docs/verification.md

@@ -35,6 +35,11 @@ Desktop band follow-up on 2026-09-07:
 
 Mobile touch follow-up on 2026-09-07:
 
-- The reported blocked scrolling was not reproduced with touch events in current desktop Chrome's mobile simulation or native swipes in Android 14 with Chrome 113. The user's physical phone was not available.
+- The reported blocked scrolling was not reproduced with touch events in current desktop Chrome's mobile simulation or native swipes in Android 14 with Chrome 113. The user's physical phone was not available; the user subsequently suspected their browser had hung.
 - Simplified mobile decoration to normal body backgrounds and removed its pseudo-elements and isolated stacking context as a compatibility measure. Native Android swipes reach the bottom of the updated page (scroll position 538.18 px, viewport 760 px, document 1298 px).
 - Updated desktop (1200 px) and mobile (390 px) scrolled screenshots are pixel-identical to the previous rendering. Checks at 1025 and 1024 px retain the desktop/mobile breakpoint and show no horizontal overflow.
+
+Mobile shadow and heading follow-up on 2026-09-07:
+
+- Added each strip's shadow to the separate mobile tape SVG. At 390 px, initial screenshot differences are confined to the tape and shadow area (the top 146 px); content positions are unchanged. The 1200 px desktop screenshot remains pixel-identical.
+- At 390 px, the Kontodaten heading's text center is 194.99 px against the viewport center of 195 px. Desktop keeps its original alignment. No horizontal overflow is present.