feat(website): responsive / mobile layouts

Make the marketing site mobile-friendly across every page and section.
Desktop appearance is unchanged; all breakpoint logic targets <=768px.

- Fluid section padding via clamp(); equal grids use auto-fit/minmax,
  asymmetric grids stack to one column via scoped-CSS media queries
- Nav: real hamburger menu on mobile (links, lang toggle, login, CTA)
- ProductMockup: scales the whole dashboard to fit (zoom) instead of
  reflowing its internals into a tall stack
- Lower oversized heading clamp() minimums so titles no longer overflow
  at ~390px (hero, page headers, final CTA, brand cover/chapter)
- HowItWorks: row-gap when steps stack so node markers clear the text
- Compare + partners tables: stacked rows now label each value with its
  column (Dezky vs hyperscaler / CSP) instead of an ambiguous header
- Footer columns, tiers, calculator and tables stack cleanly on mobile

apps/website/pages/changelog.vue

@@ -13,11 +13,12 @@ useHead({ title: () => `${copy.value.pages.changelog.label} · dezky` })
 <template>
   <LandingPageHeader :label="c.label" :title="c.title" :intro="c.intro" />
 
-  <LandingContainer pad="56px 64px 160px">
+  <LandingContainer pad="clamp(56px, 8vw, 56px) clamp(20px, 5vw, 64px) clamp(80px, 12vw, 160px)">
     <div :style="{ maxWidth: '760px' }">
       <div
         v-for="(entry, i) in c.entries" :key="i"
-        :style="{ display: 'grid', gridTemplateColumns: '160px 1fr', gap: '32px', padding: '32px 0', borderTop: `1px solid ${t.border}`, alignItems: 'start' }"
+        class="changelog-entry"
+        :style="{ display: 'grid', gap: '32px', padding: '32px 0', borderTop: `1px solid ${t.border}`, alignItems: 'start' }"
       >
         <div>
           <div :style="{ fontFamily: '\'Inter Tight\', sans-serif', fontWeight: 600, fontSize: '20px', color: t.fg, letterSpacing: '-0.015em' }">{{ entry[0] }}</div>
@@ -36,3 +37,15 @@ useHead({ title: () => `${copy.value.pages.changelog.label} · dezky` })
     </div>
   </LandingContainer>
 </template>
+
+<style scoped>
+.changelog-entry {
+  grid-template-columns: 160px 1fr;
+}
+
+@media (max-width: 768px) {
+  .changelog-entry {
+    grid-template-columns: 1fr;
+  }
+}
+</style>