diff --git a/app/[locale]/daily-lessons/page.tsx b/app/[locale]/daily-lessons/page.tsx
index 2fb843e2..cffd0275 100644
--- a/app/[locale]/daily-lessons/page.tsx
+++ b/app/[locale]/daily-lessons/page.tsx
@@ -25,7 +25,7 @@ export default async function DailyLessonsPage() {
   return (
     <div className="page-shell">
       <div className="page-shell-content section-container section-container-xl section-spacing-md space-y-6">
-        <section className="glass-card rounded-3xl p-6 md:p-8" data-testid="daily-lessons-hero">
+        <section className="glass-card rounded-3xl card-padding-lg md:p-8" data-testid="daily-lessons-hero">
           <div className="flex flex-col gap-5 md:flex-row md:items-center md:justify-between">
             <div className="space-y-3">
               <Badge
diff --git a/app/[locale]/notifications/page.tsx b/app/[locale]/notifications/page.tsx
index 2289495c..4d4c6049 100644
--- a/app/[locale]/notifications/page.tsx
+++ b/app/[locale]/notifications/page.tsx
@@ -17,7 +17,7 @@ export default async function NotificationsPage() {
   return (
     <div className="page-shell">
       <div className="page-shell-content section-container section-container-xl section-spacing-md space-y-6">
-        <section data-testid="notifications-hero" className="glass-card rounded-3xl p-6 md:p-8">
+        <section data-testid="notifications-hero" className="glass-card rounded-3xl card-padding-lg md:p-8">
           <div className="flex flex-col gap-4 md:flex-row md:items-center md:justify-between">
             <div className="space-y-2">
               <h1 className="text-2xl font-bold text-white md:text-3xl">{t('title')}</h1>
diff --git a/app/[locale]/practice/page.tsx b/app/[locale]/practice/page.tsx
index 68bd4ccc..110dca76 100644
--- a/app/[locale]/practice/page.tsx
+++ b/app/[locale]/practice/page.tsx
@@ -127,7 +127,7 @@ export default function PracticePage() {
         </div>
       </section>
 
-      <div className="space-y-4 rounded-3xl border border-border/60 bg-black/30 p-6">
+      <div className="space-y-4 rounded-3xl border border-border/60 bg-black/30 card-padding-lg md:p-7">
         <div className="flex flex-wrap gap-2">
           <DeckToggle
             label={t('savedDeck.badge')}
@@ -159,20 +159,20 @@ export default function PracticePage() {
           </Alert>
         ) : (
           <div className="space-y-4">
-            <div className="rounded-3xl border border-border/60 bg-black/40 p-8">
+            <div className="rounded-3xl border border-border/60 bg-black/40 card-padding-lg md:p-8">
               <div className="flex items-center justify-between text-xs uppercase tracking-[0.3em] text-muted-foreground">
                 <span>{currentCard?.direction === 'en-mk' ? 'EN → MK' : 'MK → EN'}</span>
                 <span>
                   {safeIndex + 1} / {total}
                 </span>
               </div>
-              <div className="mt-8 space-y-4">
+              <div className="mt-6 space-y-4">
                 <p className="text-2xl font-semibold text-white">{currentCard?.source}</p>
                 <p className={cn('text-lg text-primary transition-opacity', revealed ? 'opacity-100' : 'opacity-0')}>
                   {currentCard?.target}
                 </p>
               </div>
-              <div className="mt-10 grid gap-3 sm:grid-cols-3">
+              <div className="mt-8 grid gap-3 sm:grid-cols-3">
                 <Button variant="outline" className="rounded-full" onClick={goPrevious}>
                   <ArrowLeft className="mr-2 h-4 w-4" aria-hidden="true" />
                   Prev
diff --git a/app/[locale]/profile/page.tsx b/app/[locale]/profile/page.tsx
index 1494299d..b514ccf6 100644
--- a/app/[locale]/profile/page.tsx
+++ b/app/[locale]/profile/page.tsx
@@ -16,7 +16,7 @@ export default async function ProfilePage() {
   return (
     <div className="page-shell">
       <div className="page-shell-content section-container section-container-xl section-spacing-md space-y-6">
-        <section data-testid="profile-hero" className="glass-card rounded-3xl p-6 md:p-8">
+        <section data-testid="profile-hero" className="glass-card rounded-3xl card-padding-lg md:p-8">
           <div className="flex flex-col gap-4 md:flex-row md:items-end md:justify-between">
             <div className="space-y-3">
               <p className="text-xs font-semibold uppercase tracking-[0.3em] text-primary/80">{t('title')}</p>
diff --git a/app/[locale]/translate/page.tsx b/app/[locale]/translate/page.tsx
index af2afc2d..a02dee21 100644
--- a/app/[locale]/translate/page.tsx
+++ b/app/[locale]/translate/page.tsx
@@ -209,7 +209,7 @@ export default function TranslatePage() {
             swapLabel={t('swapDirections')}
           />
           <form
-            className="rounded-3xl border border-border/60 bg-black/30 p-6"
+            className="rounded-3xl border border-border/60 bg-black/30 card-padding-lg md:p-7"
             onSubmit={(event: FormEvent<HTMLFormElement>) => {
               event.preventDefault();
               void handleTranslate(event);
@@ -247,7 +247,7 @@ export default function TranslatePage() {
             </div>
           </form>
 
-          <section className="space-y-4 rounded-3xl border border-border/60 bg-black/30 p-6">
+          <section className="space-y-4 rounded-3xl border border-border/60 bg-black/30 card-padding-lg md:p-7">
             <div className="flex flex-wrap items-center gap-3">
               <div>
                 <p className="text-[11px] uppercase tracking-[0.35em] text-muted-foreground">{t('resultLabel')}</p>
@@ -390,7 +390,7 @@ type DirectionToggleProps = {
 
 function DirectionToggle({ options, activeId, onChange, onSwap, label, swapLabel }: DirectionToggleProps) {
   return (
-    <div className="rounded-3xl border border-border/60 bg-black/30 p-4">
+    <div className="rounded-3xl border border-border/60 bg-black/30 card-padding">
       <div className="flex flex-wrap items-center justify-between gap-3">
         <div>
           <p className="text-[11px] uppercase tracking-[0.35em] text-muted-foreground">{label}</p>
@@ -412,7 +412,7 @@ function DirectionToggle({ options, activeId, onChange, onSwap, label, swapLabel
             key={option.id}
             type="button"
             className={cn(
-              'rounded-full px-4 py-2 text-sm font-semibold transition',
+              'touch-target rounded-full px-4 py-2 text-sm font-semibold transition',
               option.id === activeId
                 ? 'bg-primary text-primary-foreground'
                 : 'bg-transparent text-muted-foreground hover:text-foreground',
@@ -441,7 +441,7 @@ function PanelToggleButton({ icon: Icon, label, active, onClick }: PanelToggleBu
       role="tab"
       aria-selected={active}
       className={cn(
-        'flex items-center gap-2 rounded-full px-4 py-2 text-xs font-semibold transition',
+        'touch-target flex items-center gap-2 rounded-full px-4 py-2 text-xs font-semibold transition',
         active ? 'bg-white text-black' : 'text-muted-foreground hover:text-white',
       )}
       onClick={onClick}
diff --git a/app/globals.css b/app/globals.css
index 0bc9070b..582f49f8 100644
--- a/app/globals.css
+++ b/app/globals.css
@@ -35,12 +35,94 @@
   --color-card: var(--card);
 }
 
+:root {
+  --space-gutter: clamp(1rem, 3vw, 1.5rem);
+  --space-gutter-wide: clamp(1.125rem, 3.5vw, 1.75rem);
+  --space-section-sm: clamp(1.25rem, 3vw, 2.25rem);
+  --space-section-md: clamp(1.75rem, 4vw, 3rem);
+  --space-section-lg: clamp(2.5rem, 5vw, 3.75rem);
+  --card-padding: clamp(1rem, 3vw, 1.5rem);
+  --card-padding-lg: clamp(1.25rem, 4vw, 2rem);
+  --gap-compact: clamp(0.5rem, 2vw, 0.75rem);
+  --gap-cozy: clamp(0.75rem, 2.5vw, 1.125rem);
+  --text-sm-mobile: clamp(0.95rem, 0.6vw + 0.88rem, 1rem);
+  --text-xs-mobile: clamp(0.85rem, 0.5vw + 0.8rem, 0.92rem);
+  --mobile-nav-height: 56px;
+  --mobile-nav-height-max: 64px;
+  --touch-target-size: 44px;
+  --safe-area-top: env(safe-area-inset-top, 0px);
+  --safe-area-bottom: env(safe-area-inset-bottom, 0px);
+}
+
 body {
   font-family: var(--font-geist-sans, "Geist", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif);
   background: var(--mk-bg);
   color: var(--mk-text);
 }
 
+.section-container {
+  width: 100%;
+  padding-inline: var(--space-gutter);
+  margin-inline: auto;
+  position: relative;
+}
+
+@media (min-width: 960px) {
+  .section-container {
+    padding-inline: var(--space-gutter-wide);
+  }
+}
+
+.section-container-sm {
+  max-width: 40rem;
+}
+
+.section-container-md {
+  max-width: 48rem;
+}
+
+.section-container-lg {
+  max-width: 64rem;
+}
+
+.section-container-xl {
+  max-width: 80rem;
+}
+
+.section-container-2xl {
+  max-width: 96rem;
+}
+
+.section-container-content {
+  max-width: 56rem;
+}
+
+.section-container-wide {
+  max-width: 70rem;
+}
+
+.section-spacing-sm {
+  padding-block: var(--space-section-sm);
+}
+
+.section-spacing-md {
+  padding-block: var(--space-section-md);
+}
+
+.section-spacing-lg {
+  padding-block: var(--space-section-lg);
+}
+
+.section-spacing-xl {
+  padding-block: calc(var(--space-section-lg) + 1rem);
+}
+
+.page-shell,
+.page-shell-content {
+  display: flex;
+  flex-direction: column;
+}
+
 @layer base {
   * {
     @apply border-border outline-ring/30;
@@ -111,24 +193,28 @@ body {
   min-height: 100vh;
   position: relative;
   z-index: 0;
-  padding: 1.5rem;
+  padding: var(--space-gutter);
+  padding-top: calc(var(--space-section-sm) / 2 + var(--safe-area-top));
+  padding-bottom: calc(var(--space-section-sm) / 2 + var(--safe-area-bottom));
 }
 
 .app-shell-scroll {
   min-height: 100vh;
+  scroll-padding-top: calc(var(--mobile-nav-height) + var(--safe-area-top));
 }
 
 .lab-hero {
   border-radius: 32px;
   border: 1px solid rgba(255, 255, 255, 0.08);
   background: linear-gradient(145deg, rgba(255, 255, 255, 0.04), rgba(0, 0, 0, 0.55));
-  padding: 1.75rem;
+  padding: var(--card-padding-lg);
+  gap: var(--gap-cozy);
   box-shadow: var(--panel-shadow);
 }
 
 .lab-grid {
   display: grid;
-  gap: 1.5rem;
+  gap: var(--gap-cozy);
 }
 
 @media (min-width: 1024px) {
@@ -141,7 +227,7 @@ body {
   border-radius: 28px;
   border: 1px solid rgba(255, 255, 255, 0.08);
   background: rgba(8, 8, 12, 0.7);
-  padding: 1.25rem;
+  padding: var(--card-padding);
   box-shadow: var(--shadow-soft);
 }
 
@@ -180,7 +266,77 @@ body {
 
 .card-grid {
   display: grid;
-  gap: 1rem;
+  gap: var(--gap-cozy);
+}
+
+.safe-top {
+  top: var(--safe-area-top);
+}
+
+.nav-toolbar {
+  min-height: var(--mobile-nav-height);
+  padding-block: clamp(0.75rem, 2vw, 0.95rem);
+}
+
+.nav-toolbar + .nav-toolbar-helper {
+  padding-top: clamp(0.35rem, 2vw, 0.75rem);
+}
+
+.nav-surface {
+  padding-top: var(--safe-area-top);
+}
+
+.shell-surface {
+  border-radius: 28px;
+  border: 1px solid rgba(255, 255, 255, 0.06);
+  background: rgba(0, 0, 0, 0.24);
+  box-shadow: var(--shadow-soft);
+}
+
+.card-padding {
+  padding: var(--card-padding);
+}
+
+.card-padding-lg {
+  padding: var(--card-padding-lg);
+}
+
+.stack-compact {
+  display: flex;
+  flex-direction: column;
+  gap: var(--gap-compact);
+}
+
+.stack-cozy {
+  display: flex;
+  flex-direction: column;
+  gap: var(--gap-cozy);
+}
+
+.touch-target {
+  min-height: var(--touch-target-size);
+  min-width: var(--touch-target-size);
+}
+
+@media (min-width: 768px) {
+  .nav-toolbar {
+    min-height: var(--mobile-nav-height-max);
+    padding-block: 1.1rem;
+  }
+}
+
+@media (max-width: 480px) {
+  .lab-hero {
+    border-radius: 24px;
+  }
+
+  .app-shell-main {
+    padding-inline: var(--space-gutter);
+  }
+
+  .section-heading {
+    font-size: clamp(1.15rem, 3vw, 1.5rem);
+  }
 }
 
 @media (min-width: 960px) {
diff --git a/components/layout/TopNav.tsx b/components/layout/TopNav.tsx
index 9f140df5..d5a8e80d 100644
--- a/components/layout/TopNav.tsx
+++ b/components/layout/TopNav.tsx
@@ -85,13 +85,13 @@ export function TopNav({
 
       <nav
         className={cn(
-          'w-full border-b border-white/5 bg-[#050918]/90 backdrop-blur-xl shadow-lg shadow-black/30 z-40',
-          sticky && 'sticky top-0',
+          'nav-surface w-full border-b border-white/5 bg-[#050918]/90 backdrop-blur-xl shadow-lg shadow-black/30 z-40',
+          sticky && 'sticky safe-top',
           className
         )}
         aria-label={t('label')}
       >
-        <div className="section-container section-container-wide flex flex-wrap items-center justify-between gap-3 py-3">
+        <div className="section-container section-container-wide nav-toolbar flex flex-wrap items-center justify-between gap-3">
           <Link
             href={`/${locale}`}
             className="flex items-center gap-2 transition-opacity hover:opacity-80"
@@ -108,7 +108,7 @@ export function TopNav({
           </div>
         </div>
 
-        <div className="section-container section-container-wide pb-3">
+        <div className="nav-toolbar-helper section-container section-container-wide pb-3 hidden sm:block">
           <MissionSummaryBanner
             mission={mission}
             state={missionState}
@@ -137,7 +137,7 @@ type MissionSummaryBannerProps = {
 function MissionSummaryBanner({ mission, state, error, onRefresh, t, buildHref }: MissionSummaryBannerProps) {
   if (state === 'loading') {
     return (
-      <div className="flex items-center gap-3 rounded-2xl border border-white/5 bg-[#0f162e]/80 px-4 py-3 text-sm text-slate-300">
+      <div className="flex items-center gap-3 rounded-2xl border border-white/5 bg-[#0f162e]/80 card-padding text-sm text-slate-300">
         <Loader2 className="h-4 w-4 animate-spin" aria-hidden="true" />
         {t('summaryLoading')}
       </div>
@@ -146,7 +146,7 @@ function MissionSummaryBanner({ mission, state, error, onRefresh, t, buildHref }
 
   if (state === 'error') {
     return (
-      <div className="flex flex-wrap items-center gap-3 rounded-2xl border border-red-500/40 bg-red-900/20 px-4 py-3 text-sm text-red-200">
+      <div className="flex flex-wrap items-center gap-3 rounded-2xl border border-red-500/40 bg-red-900/20 card-padding text-sm text-red-200">
         <div className="flex items-center gap-2">
           <AlertCircle className="h-4 w-4" aria-hidden="true" />
           <span>{error ?? t('summaryError')}</span>
@@ -154,7 +154,7 @@ function MissionSummaryBanner({ mission, state, error, onRefresh, t, buildHref }
         <button
           type="button"
           onClick={onRefresh}
-          className="rounded-full border border-red-400/60 px-3 py-1 text-xs font-semibold text-red-100 transition-all hover:bg-red-500/20"
+          className="touch-target rounded-full border border-red-400/60 px-3 py-1 text-xs font-semibold text-red-100 transition-all hover:bg-red-500/20"
         >
           {t('retry')}
         </button>
@@ -171,8 +171,8 @@ function MissionSummaryBanner({ mission, state, error, onRefresh, t, buildHref }
   });
 
   return (
-    <div className="flex flex-wrap items-center gap-4 rounded-2xl border border-white/5 bg-[#0f162e]/80 px-4 py-4">
-      <div className="flex flex-1 flex-wrap items-center gap-4">
+    <div className="flex flex-wrap items-center gap-3 rounded-2xl border border-white/5 bg-[#0f162e]/80 card-padding">
+      <div className="flex flex-1 flex-wrap items-center gap-3">
         <div className="flex items-center gap-3">
           <span className="flex h-11 w-11 items-center justify-center rounded-2xl bg-[var(--brand-red)]/10 text-[var(--brand-red)]">
             <Flame className="h-5 w-5" aria-hidden="true" />
diff --git a/components/notifications/NotificationsInbox.tsx b/components/notifications/NotificationsInbox.tsx
index ea7aea24..147d7c95 100644
--- a/components/notifications/NotificationsInbox.tsx
+++ b/components/notifications/NotificationsInbox.tsx
@@ -54,7 +54,7 @@ export function NotificationsInbox({ className, dataTestId }: NotificationsInbox
   const notifications = data?.notifications || [];
   const unreadCount = notifications.filter((n) => !n.isRead).length;
   const cardClasses = cn(
-    'glass-card border border-white/10 p-6 md:p-8 text-white space-y-6',
+    'glass-card border border-white/10 card-padding-lg md:p-8 text-white space-y-6',
     className
   );
 
diff --git a/components/notifications/ReminderSettingsCard.tsx b/components/notifications/ReminderSettingsCard.tsx
index f48a6928..85e8d507 100644
--- a/components/notifications/ReminderSettingsCard.tsx
+++ b/components/notifications/ReminderSettingsCard.tsx
@@ -95,7 +95,7 @@ export function ReminderSettingsCard({ className, dataTestId }: ReminderSettings
   return (
     <section
       className={cn(
-        'glass-card rounded-3xl border border-white/15 bg-white/5 p-6 text-white space-y-6',
+        'glass-card rounded-3xl border border-white/15 bg-white/5 card-padding-lg md:p-7 text-white space-y-6',
         className
       )}
       data-testid={dataTestId}
diff --git a/components/shell/AppShell.tsx b/components/shell/AppShell.tsx
index 7d486a52..a75c0376 100644
--- a/components/shell/AppShell.tsx
+++ b/components/shell/AppShell.tsx
@@ -14,7 +14,7 @@ export function AppShell({ children }: { children: ReactNode }) {
       <div className="app-shell-main lg:ml-[72px] xl:ml-72">
         <div className="app-shell-scroll">
           <ShellHeader onToggleSidebar={() => setSidebarOpen((prev) => !prev)} />
-          <main id="main-content" className="space-y-8" role="main">
+          <main id="main-content" className="space-y-6 md:space-y-8" role="main">
             {children}
           </main>
         </div>
diff --git a/components/shell/ShellHeader.tsx b/components/shell/ShellHeader.tsx
index d067592e..301f309a 100644
--- a/components/shell/ShellHeader.tsx
+++ b/components/shell/ShellHeader.tsx
@@ -17,13 +17,13 @@ export function ShellHeader({ onToggleSidebar }: ShellHeaderProps) {
   const buildHref = (path: string) => `/${locale}${path}`;
 
   return (
-    <header className="mb-8 rounded-3xl border border-border/50 bg-black/30 p-4 shadow-xl">
-      <div className="flex flex-wrap items-center justify-between gap-4">
+    <header className="mb-6 shell-surface nav-toolbar px-4 md:px-6">
+      <div className="flex flex-wrap items-center justify-between gap-3">
         <div className="flex items-center gap-3">
           <button
             type="button"
             onClick={onToggleSidebar}
-            className="inline-flex items-center gap-2 rounded-full border border-border/60 px-3 py-2 text-sm text-muted-foreground lg:hidden"
+            className="touch-target inline-flex items-center gap-2 rounded-full border border-border/60 px-3 py-2 text-sm text-muted-foreground lg:hidden"
           >
             <Menu className="h-4 w-4" aria-hidden="true" />
             {localeT("menu")}
@@ -52,7 +52,7 @@ export function ShellHeader({ onToggleSidebar }: ShellHeaderProps) {
           </Button>
         </div>
       </div>
-      <p className="mt-4 text-sm text-muted-foreground">{localeT("tagline")}</p>
+      <p className="mt-2 hidden text-xs text-muted-foreground sm:block">{localeT("tagline")}</p>
     </header>
   );
 }
diff --git a/components/ui/button.tsx b/components/ui/button.tsx
index 351af82f..4ddff7bd 100644
--- a/components/ui/button.tsx
+++ b/components/ui/button.tsx
@@ -5,7 +5,7 @@ import { cva, type VariantProps } from "class-variance-authority"
 import { cn } from "@/lib/utils"
 
 const buttonVariants = cva(
-  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-2xl border border-transparent text-sm font-semibold tracking-tight transition-all duration-200 ease-out disabled:pointer-events-none disabled:opacity-60 [&_svg]:pointer-events-none [&_svg:not([class*='size-'])]:size-4 shrink-0 [&_svg]:shrink-0 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/50 focus-visible:ring-offset-2 focus-visible:ring-offset-background aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive hover:-translate-y-0.5 active:translate-y-0",
+  "inline-flex min-h-[44px] min-w-[44px] items-center justify-center gap-2 whitespace-nowrap rounded-2xl border border-transparent text-sm font-semibold tracking-tight transition-all duration-200 ease-out disabled:pointer-events-none disabled:opacity-60 [&_svg]:pointer-events-none [&_svg:not([class*='size-'])]:size-4 shrink-0 [&_svg]:shrink-0 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/50 focus-visible:ring-offset-2 focus-visible:ring-offset-background aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive hover:-translate-y-0.5 active:translate-y-0",
   {
     variants: {
       variant: {
@@ -22,10 +22,10 @@ const buttonVariants = cva(
       },
       size: {
         default: "h-12 px-7 py-2.5 has-[>svg]:px-5",
-        sm: "h-10 rounded-xl gap-1.5 px-4 has-[>svg]:px-3 text-sm",
+        sm: "h-11 rounded-xl gap-1.5 px-4 has-[>svg]:px-3 text-sm",
         lg: "h-14 rounded-3xl px-9 has-[>svg]:px-7 text-base",
         icon: "size-12",
-        "icon-sm": "size-10",
+        "icon-sm": "h-11 w-11",
         "icon-lg": "size-14",
       },
     },