fix(ui): comprehensive mobile optimizations across homepage and blocks

- fix: bottom nav and footer padding collision
- fix: reveal animation flickering (Certificates, SubCompanyTiles)
- fix: tooltip flyout overflow on mobile in Germany map
- fix: flex direction for 'Projekt anfragen' and Service Detail icons
- fix: text alignment and spacing issues in ReferencesSlider
- fix: reduce excessive whitespace above footer

components/blocks/CertificatesBlock.tsx

@@ -140,7 +140,7 @@ export function CertificatesBlock({ badge, title, description, certificates = de
           variants={containerVariants}
           initial="hidden"
           whileInView="show"
-          viewport={{ once: true, margin: "-50px" }}
+          viewport={{ once: true, amount: 0.1 }}
         >
           {certificates.map((cert, index) => {
             const isIso = cert.type === 'iso';