diff --git a/components/AlbyInstaller.tsx b/components/AlbyInstaller.tsx
index 60cca4c..40f4445 100644
--- a/components/AlbyInstaller.tsx
+++ b/components/AlbyInstaller.tsx
@@ -1,5 +1,6 @@
 import { useEffect, useState, useCallback } from 'react'
 import { getAlbyService } from '@/lib/alby'
+import { Button } from './ui'
 
 interface AlbyInstallerProps {
   onInstalled?: () => void
@@ -43,18 +44,20 @@ function InstallerActions({ onInstalled, markInstalled }: InstallerActionsProps)
           href="https://getalby.com/"
           target="_blank"
           rel="noopener noreferrer"
-          className="inline-flex items-center justify-center px-4 py-2 border border-neon-cyan/50 text-sm font-medium rounded-lg text-neon-cyan bg-neon-cyan/20 hover:bg-neon-cyan/30 hover:shadow-glow-cyan focus:outline-none focus:ring-2 focus:ring-neon-cyan transition-all"
         >
-          Install Alby
+          <Button variant="primary" size="small">
+            Install Alby
+          </Button>
         </a>
-        <button
+        <Button
+          variant="secondary"
+          size="small"
           onClick={() => {
             void connect()
           }}
-          className="inline-flex items-center justify-center px-4 py-2 border border-neon-cyan/30 text-sm font-medium rounded-lg text-cyber-accent bg-cyber-light hover:bg-cyber-dark hover:border-neon-cyan/50 focus:outline-none focus:ring-2 focus:ring-neon-cyan transition-all"
         >
           Already installed? Connect
-        </button>
+        </Button>
       </div>
     </div>
   )
diff --git a/components/ArticleCard.tsx b/components/ArticleCard.tsx
index f34c58e..1e46112 100644
--- a/components/ArticleCard.tsx
+++ b/components/ArticleCard.tsx
@@ -3,6 +3,7 @@ import { useNostrAuth } from '@/hooks/useNostrAuth'
 import { useArticlePayment } from '@/hooks/useArticlePayment'
 import { ArticlePreview } from './ArticlePreview'
 import { PaymentModal } from './PaymentModal'
+import { Card } from './ui'
 import { t } from '@/lib/i18n'
 import Link from 'next/link'
 
@@ -69,7 +70,7 @@ export function ArticleCard({ article, onUnlock }: ArticleCardProps): React.Reac
   }, connect)
 
   return (
-    <article className="border border-neon-cyan/30 rounded-lg p-6 bg-cyber-dark hover:border-neon-cyan/50 hover:shadow-glow-cyan transition-all">
+    <Card variant="interactive" className="mb-0">
       <ArticleHeader article={article} />
       <div className="text-cyber-accent mb-4">
         <ArticlePreview
@@ -89,6 +90,6 @@ export function ArticleCard({ article, onUnlock }: ArticleCardProps): React.Reac
           void handlePaymentComplete()
         }}
       />
-    </article>
+    </Card>
   )
 }
diff --git a/components/ArticleFilters.tsx b/components/ArticleFilters.tsx
index 8b03450..4a9b028 100644
--- a/components/ArticleFilters.tsx
+++ b/components/ArticleFilters.tsx
@@ -1,5 +1,6 @@
 import React from 'react'
 import type { Article } from '@/types/nostr'
+import { Card } from './ui'
 import { t } from '@/lib/i18n'
 import { AuthorFilter } from './AuthorFilter'
 
@@ -123,9 +124,9 @@ export function ArticleFiltersComponent({
     filters.category !== null
 
   return (
-    <div className="bg-cyber-dark border border-neon-cyan/30 rounded-lg p-4 mb-6 shadow-glow-cyan">
+    <Card variant="default" className="mb-6 shadow-glow-cyan">
       <FiltersHeader hasActiveFilters={hasActiveFilters} onClear={handleClearFilters} />
       <FiltersGrid data={data} filters={filters} onFiltersChange={onFiltersChange} />
-    </div>
+    </Card>
   )
 }
diff --git a/components/ArticleFormButtons.tsx b/components/ArticleFormButtons.tsx
index 434e968..3616c0e 100644
--- a/components/ArticleFormButtons.tsx
+++ b/components/ArticleFormButtons.tsx
@@ -1,3 +1,4 @@
+import { Button } from './ui'
 import { t } from '@/lib/i18n'
 
 interface ArticleFormButtonsProps {
@@ -10,21 +11,23 @@ export function ArticleFormButtons({ loading, onCancel }: ArticleFormButtonsProp
   return (
     <div className="space-y-3 pt-4">
       <div className="flex gap-3">
-        <button
+        <Button
           type="submit"
+          variant="primary"
           disabled={loading}
-          className="flex-1 px-4 py-2 bg-neon-cyan/20 hover:bg-neon-cyan/30 text-neon-cyan rounded-lg font-medium transition-all border border-neon-cyan/50 hover:shadow-glow-cyan disabled:opacity-50 disabled:cursor-not-allowed"
+          loading={loading}
+          className="flex-1"
         >
           {loading ? t('publish.publishing') : t('publish.button')}
-        </button>
+        </Button>
         {onCancel && (
-          <button
+          <Button
             type="button"
+            variant="ghost"
             onClick={onCancel}
-            className="px-4 py-2 bg-cyber-dark hover:bg-cyber-dark/80 text-cyber-accent rounded-lg font-medium transition-colors border border-cyber-accent/30 hover:border-neon-cyan/50"
           >
             {t('common.back')}
-          </button>
+          </Button>
         )}
       </div>
     </div>
diff --git a/components/ArticlePreview.tsx b/components/ArticlePreview.tsx
index ee06fdd..c3ee8ab 100644
--- a/components/ArticlePreview.tsx
+++ b/components/ArticlePreview.tsx
@@ -1,4 +1,5 @@
 import type { Article } from '@/types/nostr'
+import { Button } from './ui'
 import { ArticlePages } from './ArticlePages'
 
 interface ArticlePreviewProps {
@@ -25,13 +26,14 @@ export function ArticlePreview({ article, loading, onUnlock }: ArticlePreviewPro
           <p className="text-sm text-cyber-accent/70 mb-4">
             Contenu complet disponible après un zap de {article.zapAmount} sats
           </p>
-          <button
+          <Button
+            variant="success"
             onClick={onUnlock}
             disabled={loading}
-            className="px-4 py-2 bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded-lg font-medium transition-all border border-neon-green/50 hover:shadow-glow-green disabled:opacity-50"
+            loading={loading}
           >
             {loading ? 'Traitement...' : `Débloquer avec ${article.zapAmount} sats zap`}
-          </button>
+          </Button>
         </div>
       </div>
   )
diff --git a/components/ArticleReviews.tsx b/components/ArticleReviews.tsx
index f90a300..9184dc9 100644
--- a/components/ArticleReviews.tsx
+++ b/components/ArticleReviews.tsx
@@ -2,6 +2,7 @@ import { useCallback, useEffect, useState } from 'react'
 import type { Review, Article } from '@/types/nostr'
 import { getReviewsForArticle } from '@/lib/reviews'
 import { getReviewTipsForArticle } from '@/lib/reviewAggregation'
+import { Card, ErrorState, Button } from './ui'
 import { ReviewForm } from './ReviewForm'
 import { ReviewTipForm } from './ReviewTipForm'
 import { t } from '@/lib/i18n'
@@ -17,7 +18,7 @@ export function ArticleReviews({ article, authorPubkey }: ArticleReviewsProps):
   const tipSelection = useReviewTipSelection({ article, reviews: data.reviews, reload: data.reload })
 
   return (
-    <div className="border border-neon-cyan/30 rounded-lg p-4 bg-cyber-dark space-y-4">
+    <Card variant="default" className="space-y-4">
       <ArticleReviewsHeader tips={data.tips} onAddReview={reviewForm.open} />
       {reviewForm.show && (
         <ReviewForm
@@ -27,13 +28,13 @@ export function ArticleReviews({ article, authorPubkey }: ArticleReviewsProps):
         />
       )}
       {data.loading && <p className="text-sm text-cyber-accent">{t('common.loading')}</p>}
-      {data.error && <p className="text-sm text-red-400">{data.error}</p>}
+      {data.error && <ErrorState message={data.error} />}
       {!data.loading && !data.error && data.reviews.length === 0 && !reviewForm.show && (
         <p className="text-sm text-cyber-accent/70">{t('review.empty')}</p>
       )}
       {!data.loading && !data.error && <ArticleReviewsList reviews={data.reviews} onTipReview={tipSelection.select} />}
       <SelectedReviewTipForm selection={tipSelection} />
-    </div>
+    </Card>
   )
 }
 
@@ -163,12 +164,9 @@ function ArticleReviewsHeader({ tips, onAddReview }: { tips: number; onAddReview
       <h3 className="text-lg font-semibold text-neon-cyan">{t('review.title')}</h3>
       <div className="flex items-center gap-4">
         <span className="text-sm text-cyber-accent/70">{t('review.tips.total', { amount: tips })}</span>
-        <button
-          onClick={onAddReview}
-          className="px-3 py-1 text-sm bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded-lg font-medium transition-all border border-neon-green/50"
-        >
+        <Button variant="success" size="small" onClick={onAddReview}>
           {t('review.add')}
-        </button>
+        </Button>
       </div>
     </div>
   )
@@ -192,14 +190,16 @@ function ArticleReviewsList({ reviews, onTipReview }: { reviews: Review[]; onTip
             <span>{t('review.reviewer')}: {formatPubkey(r.reviewerPubkey)}</span>
             <span>•</span>
             <span>{formatDate(r.createdAt)}</span>
-            <button
+            <Button
+              variant="success"
+              size="small"
               onClick={() => {
                 onTipReview(r.id)
               }}
-              className="ml-auto px-2 py-1 text-xs bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded transition-all border border-neon-green/50"
+              className="ml-auto"
             >
               {t('review.tip.button')}
-            </button>
+            </Button>
           </div>
         </div>
       ))}
diff --git a/components/ArticlesList.tsx b/components/ArticlesList.tsx
index 1271035..4d19dcc 100644
--- a/components/ArticlesList.tsx
+++ b/components/ArticlesList.tsx
@@ -1,5 +1,6 @@
 import type { Article } from '@/types/nostr'
 import { ArticleCard } from './ArticleCard'
+import { ErrorState, EmptyState } from './ui'
 import { t } from '@/lib/i18n'
 
 interface ArticlesListProps {
@@ -20,21 +21,11 @@ function LoadingState(): React.ReactElement {
   )
 }
 
-function ErrorState({ message }: { message: string }): React.ReactElement {
+function ArticlesEmptyState({ hasAny }: { hasAny: boolean }): React.ReactElement {
   return (
-    <div className="bg-red-900/20 border border-red-500/50 rounded-lg p-4 mb-4">
-      <p className="text-red-400">{message}</p>
-    </div>
-  )
-}
-
-function EmptyState({ hasAny }: { hasAny: boolean }): React.ReactElement {
-  return (
-    <div className="text-center py-12">
-      <p className="text-cyber-accent/70">
-        {hasAny ? t('common.empty.articles.filtered') : t('common.empty.articles')}
-      </p>
-    </div>
+    <EmptyState
+      title={hasAny ? t('common.empty.articles.filtered') : t('common.empty.articles')}
+    />
   )
 }
 
@@ -53,7 +44,7 @@ export function ArticlesList({
     return <ErrorState message={error} />
   }
   if (articles.length === 0) {
-    return <EmptyState hasAny={allArticles.length > 0} />
+    return <ArticlesEmptyState hasAny={allArticles.length > 0} />
   }
 
   return (
diff --git a/components/AuthorCard.tsx b/components/AuthorCard.tsx
index 91703de..be6016b 100644
--- a/components/AuthorCard.tsx
+++ b/components/AuthorCard.tsx
@@ -1,6 +1,7 @@
-import Link from 'next/link'
+import { useRouter } from 'next/router'
 import Image from 'next/image'
 import type { Article } from '@/types/nostr'
+import { Card } from './ui'
 import { t } from '@/lib/i18n'
 
 interface AuthorCardProps {
@@ -8,14 +9,16 @@ interface AuthorCardProps {
 }
 
 export function AuthorCard({ presentation }: AuthorCardProps): React.ReactElement {
+  const router = useRouter()
   const authorName = presentation.title.replace(/^Présentation de /, '') || t('common.author')
   const totalBTC = (presentation.totalSponsoring ?? 0) / 100_000_000
 
+  const handleClick = (): void => {
+    void router.push(`/author/${presentation.pubkey}`)
+  }
+
   return (
-    <Link
-      href={`/author/${presentation.pubkey}`}
-      className="block border border-neon-cyan/20 rounded-lg p-6 bg-cyber-dark/50 hover:bg-cyber-dark hover:border-neon-cyan/40 transition-all hover:shadow-glow-cyan"
-    >
+    <Card variant="interactive" onClick={handleClick} className="bg-cyber-dark/50">
       <div className="flex items-start gap-4">
         {presentation.bannerUrl && (
           <div className="relative w-20 h-20 rounded-lg overflow-hidden border border-neon-cyan/20 flex-shrink-0">
@@ -37,6 +40,6 @@ export function AuthorCard({ presentation }: AuthorCardProps): React.ReactElemen
           )}
         </div>
       </div>
-    </Link>
+    </Card>
   )
 }
diff --git a/components/AuthorsList.tsx b/components/AuthorsList.tsx
index 9140d8b..b99e781 100644
--- a/components/AuthorsList.tsx
+++ b/components/AuthorsList.tsx
@@ -1,5 +1,6 @@
 import type { Article } from '@/types/nostr'
 import { AuthorCard } from './AuthorCard'
+import { ErrorState, EmptyState } from './ui'
 import { t } from '@/lib/i18n'
 
 interface AuthorsListProps {
@@ -17,21 +18,11 @@ function LoadingState(): React.ReactElement {
   )
 }
 
-function ErrorState({ message }: { message: string }): React.ReactElement {
+function AuthorsEmptyState({ hasAny }: { hasAny: boolean }): React.ReactElement {
   return (
-    <div className="bg-red-900/20 border border-red-500/50 rounded-lg p-4 mb-4">
-      <p className="text-red-400">{message}</p>
-    </div>
-  )
-}
-
-function EmptyState({ hasAny }: { hasAny: boolean }): React.ReactElement {
-  return (
-    <div className="text-center py-12">
-      <p className="text-cyber-accent/70">
-        {hasAny ? t('common.empty.authors.filtered') : t('common.empty.authors')}
-      </p>
-    </div>
+    <EmptyState
+      title={hasAny ? t('common.empty.authors.filtered') : t('common.empty.authors')}
+    />
   )
 }
 
@@ -43,7 +34,7 @@ export function AuthorsList({ authors, allAuthors, loading, error }: AuthorsList
     return <ErrorState message={error} />
   }
   if (authors.length === 0) {
-    return <EmptyState hasAny={allAuthors.length > 0} />
+    return <AuthorsEmptyState hasAny={allAuthors.length > 0} />
   }
 
   return (
diff --git a/components/ClearButton.tsx b/components/ClearButton.tsx
index 970660d..0fade62 100644
--- a/components/ClearButton.tsx
+++ b/components/ClearButton.tsx
@@ -7,9 +7,13 @@ interface ClearButtonProps {
 export function ClearButton({ onClick }: ClearButtonProps): React.ReactElement {
   return (
     <button
-      onClick={onClick}
-      className="absolute inset-y-0 right-0 pr-3 flex items-center text-neon-cyan/70 hover:text-neon-cyan transition-colors"
+      onClick={(e) => {
+        e.preventDefault()
+        onClick()
+      }}
+      className="text-neon-cyan/70 hover:text-neon-cyan transition-colors focus:outline-none focus:ring-2 focus:ring-neon-cyan rounded"
       aria-label={t('search.clear')}
+      type="button"
     >
       <svg className="h-5 w-5" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 20 20" fill="currentColor">
         <path
diff --git a/components/ConditionalPublishButton.tsx b/components/ConditionalPublishButton.tsx
index 2cd3a31..19af9af 100644
--- a/components/ConditionalPublishButton.tsx
+++ b/components/ConditionalPublishButton.tsx
@@ -3,15 +3,16 @@ import Image from 'next/image'
 import { useNostrAuth } from '@/hooks/useNostrAuth'
 import { useAuthorPresentation } from '@/hooks/useAuthorPresentation'
 import { useEffect, useState } from 'react'
+import { Button } from './ui'
 import { t } from '@/lib/i18n'
 import type { Article } from '@/types/nostr'
 
-const buttonClassName = 'px-4 py-2 bg-neon-cyan/20 hover:bg-neon-cyan/30 text-neon-cyan rounded-lg text-sm font-medium transition-all border border-neon-cyan/50 hover:shadow-glow-cyan'
-
 function CreateAuthorPageLink(): React.ReactElement {
   return (
-    <Link href="/presentation" className={buttonClassName}>
-      {t('nav.createAuthorPage')}
+    <Link href="/presentation">
+      <Button variant="primary" size="small">
+        {t('nav.createAuthorPage')}
+      </Button>
     </Link>
   )
 }
diff --git a/components/ConnectButton.tsx b/components/ConnectButton.tsx
index 7104566..010486e 100644
--- a/components/ConnectButton.tsx
+++ b/components/ConnectButton.tsx
@@ -3,6 +3,7 @@ import { ConnectedUserMenu } from './ConnectedUserMenu'
 import { RecoveryStep } from './CreateAccountModalSteps'
 import { UnlockAccountModal } from './UnlockAccountModal'
 import type { NostrProfile } from '@/types/nostr'
+import { Button } from './ui'
 import { t } from '@/lib/i18n'
 import { getConnectButtonMode } from './connectButton/connectButtonMode'
 import { useAutoConnect, useConnectButtonUiState } from './connectButton/useConnectButtonUiState'
@@ -20,20 +21,22 @@ function ConnectForm({
 }): React.ReactElement {
   return (
     <div className="flex flex-col gap-2">
-      <button
+      <Button
+        variant="primary"
         onClick={onCreateAccount}
         disabled={loading}
-        className="px-6 py-2 bg-neon-cyan/20 hover:bg-neon-cyan/30 text-neon-cyan rounded-lg font-medium transition-all border border-neon-cyan/50 hover:shadow-glow-cyan disabled:opacity-50"
+        size="large"
       >
         {t('connect.createAccount')}
-      </button>
-      <button
+      </Button>
+      <Button
+        variant="secondary"
         onClick={onUnlock}
         disabled={loading}
-        className="px-6 py-2 bg-gray-100 hover:bg-gray-200 text-gray-700 rounded-lg font-medium transition-colors disabled:opacity-50"
+        size="large"
       >
         {t('connect.connect')}
-      </button>
+      </Button>
       {error && <p className="text-sm text-red-400">{error}</p>}
     </div>
   )
diff --git a/components/PaymentModal.tsx b/components/PaymentModal.tsx
index 46e8528..46a0276 100644
--- a/components/PaymentModal.tsx
+++ b/components/PaymentModal.tsx
@@ -3,7 +3,7 @@ import QRCode from 'react-qr-code'
 import type { AlbyInvoice } from '@/types/alby'
 import { getAlbyService, isWebLNAvailable } from '@/lib/alby'
 import { AlbyInstaller } from './AlbyInstaller'
-import { Modal } from './ui/Modal'
+import { Modal, Button } from './ui'
 import { t } from '@/lib/i18n'
 
 interface PaymentModalProps {
@@ -94,20 +94,22 @@ function PaymentActions({
 }): React.ReactElement {
   return (
     <div className="flex gap-2">
-      <button
+      <Button
+        variant="secondary"
         onClick={() => {
           void onCopy()
         }}
-        className="flex-1 px-4 py-2 bg-cyber-light border border-neon-cyan/30 hover:border-neon-cyan/50 hover:bg-cyber-dark text-cyber-accent hover:text-neon-cyan rounded-lg font-medium transition-colors"
+        className="flex-1"
       >
         {copied ? t('payment.modal.copied') : t('payment.modal.copyInvoice')}
-      </button>
-      <button
+      </Button>
+      <Button
+        variant="primary"
         onClick={onOpenWallet}
-        className="flex-1 px-4 py-2 bg-neon-cyan/20 border border-neon-cyan/50 hover:bg-neon-cyan/30 hover:border-neon-cyan text-neon-cyan hover:text-neon-green rounded-lg font-medium transition-colors"
+        className="flex-1"
       >
         {t('payment.modal.payWithAlby')}
-      </button>
+      </Button>
     </div>
   )
 }
diff --git a/components/SearchBar.tsx b/components/SearchBar.tsx
index 8fb2fb4..62af3ad 100644
--- a/components/SearchBar.tsx
+++ b/components/SearchBar.tsx
@@ -1,6 +1,7 @@
 import { useState, useEffect } from 'react'
 import { SearchIcon } from './SearchIcon'
 import { ClearButton } from './ClearButton'
+import { Input } from './ui'
 import { t } from '@/lib/i18n'
 
 interface SearchBarProps {
@@ -29,18 +30,14 @@ export function SearchBar({ value, onChange, placeholder }: SearchBarProps): Rea
   }
 
   return (
-    <div className="relative">
-      <div className="absolute inset-y-0 left-0 pl-3 flex items-center pointer-events-none">
-        <SearchIcon />
-      </div>
-      <input
-        type="text"
-        value={localValue}
-        onChange={handleChange}
-        placeholder={defaultPlaceholder}
-        className="block w-full pl-10 pr-10 py-2 border border-neon-cyan/30 rounded-lg focus:ring-2 focus:ring-neon-cyan focus:border-neon-cyan bg-cyber-dark text-cyber-accent placeholder-cyber-accent/50 hover:border-neon-cyan/50 transition-colors"
-      />
-      {localValue && <ClearButton onClick={handleClear} />}
-    </div>
+    <Input
+      type="text"
+      value={localValue}
+      onChange={handleChange}
+      placeholder={defaultPlaceholder}
+      leftIcon={<SearchIcon />}
+      rightIcon={localValue ? <ClearButton onClick={handleClear} /> : undefined}
+      className="pr-10"
+    />
   )
 }
diff --git a/components/SponsoringForm.tsx b/components/SponsoringForm.tsx
index ee59ad5..c35d3c3 100644
--- a/components/SponsoringForm.tsx
+++ b/components/SponsoringForm.tsx
@@ -1,6 +1,7 @@
 import { useState } from 'react'
 import { nostrService } from '@/lib/nostr'
 import { useNostrAuth } from '@/hooks/useNostrAuth'
+import { Button, Card, Textarea, ErrorState } from './ui'
 import { t } from '@/lib/i18n'
 import { sponsoringPaymentService } from '@/lib/sponsoringPayment'
 import type { AuthorPresentationArticle } from '@/types/nostr'
@@ -129,36 +130,38 @@ async function submitSponsoring(params: {
 
 function SponsoringConnectRequired(params: { onConnect: () => void }): React.ReactElement {
   return (
-    <div className="border border-neon-cyan/30 rounded-lg p-4 bg-cyber-dark">
+    <Card variant="default">
       <p className="text-cyber-accent mb-4">{t('sponsoring.form.connectRequired')}</p>
-      <button onClick={params.onConnect} className="px-4 py-2 bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded-lg font-medium transition-all border border-neon-green/50">
+      <Button variant="success" onClick={params.onConnect}>
         {t('connect.connect')}
-      </button>
-    </div>
+      </Button>
+    </Card>
   )
 }
 
 function SponsoringNoAddress(): React.ReactElement {
   return (
-    <div className="border border-neon-cyan/30 rounded-lg p-4 bg-cyber-dark">
+    <Card variant="default">
       <p className="text-cyber-accent">{t('sponsoring.form.error.noAddress')}</p>
-    </div>
+    </Card>
   )
 }
 
 function SponsoringInstructions(params: { instructions: SponsoringInstructionsState; onClose: () => void; onCancel: () => void }): React.ReactElement {
   return (
-    <div className="border border-neon-cyan/30 rounded-lg p-4 bg-cyber-dark space-y-4" role="dialog" aria-modal="true">
-      <h3 className="text-lg font-semibold text-neon-cyan">{t('sponsoring.form.title')}</h3>
-      <p className="text-sm text-cyber-accent/70">{t('sponsoring.form.instructions', { authorAddress: params.instructions.authorAddress, platformAddress: params.instructions.platformAddress, authorAmount: params.instructions.authorBtc, platformAmount: params.instructions.platformBtc })}</p>
-      <div className="flex gap-3">
-        <button type="button" onClick={params.onClose} className="px-4 py-2 bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded-lg font-medium transition-all border border-neon-green/50">
-          {t('common.close')}
-        </button>
-        <button type="button" onClick={params.onCancel} className="px-4 py-2 bg-neon-cyan/10 hover:bg-neon-cyan/20 text-neon-cyan rounded-lg font-medium transition-all border border-neon-cyan/30">
-          {t('common.cancel')}
-        </button>
-      </div>
+    <div role="dialog" aria-modal="true">
+      <Card variant="default" className="space-y-4">
+        <h3 className="text-lg font-semibold text-neon-cyan">{t('sponsoring.form.title')}</h3>
+        <p className="text-sm text-cyber-accent/70">{t('sponsoring.form.instructions', { authorAddress: params.instructions.authorAddress, platformAddress: params.instructions.platformAddress, authorAmount: params.instructions.authorBtc, platformAmount: params.instructions.platformBtc })}</p>
+        <div className="flex gap-3">
+          <Button type="button" variant="success" onClick={params.onClose}>
+            {t('common.close')}
+          </Button>
+          <Button type="button" variant="ghost" onClick={params.onCancel}>
+            {t('common.cancel')}
+          </Button>
+        </div>
+      </Card>
     </div>
   )
 }
@@ -175,29 +178,24 @@ function SponsoringFormView(params: {
     <form onSubmit={params.onSubmit} className="border border-neon-cyan/30 rounded-lg p-4 bg-cyber-dark space-y-4">
       <h3 className="text-lg font-semibold text-neon-cyan">{t('sponsoring.form.title')}</h3>
       <p className="text-sm text-cyber-accent/70">{t('sponsoring.form.description', { amount: '0.046' })}</p>
-      <div>
-        <label htmlFor="sponsoring-text" className="block text-sm font-medium text-cyber-accent mb-1">
-          {t('sponsoring.form.text.label')} <span className="text-cyber-accent/50">({t('common.optional')})</span>
-        </label>
-        <textarea
-          id="sponsoring-text"
-          value={params.text}
-          onChange={(e) => params.setText(e.target.value)}
-          placeholder={t('sponsoring.form.text.placeholder')}
-          rows={3}
-          className="w-full px-3 py-2 bg-cyber-darker border border-neon-cyan/30 rounded text-cyber-accent focus:border-neon-cyan focus:outline-none"
-        />
-        <p className="text-xs text-cyber-accent/70 mt-1">{t('sponsoring.form.text.help')}</p>
-      </div>
-      {params.error && <div className="p-3 bg-red-900/20 border border-red-500/50 rounded text-red-400 text-sm">{params.error}</div>}
+      <Textarea
+        id="sponsoring-text"
+        label={`${t('sponsoring.form.text.label')} (${t('common.optional')})`}
+        value={params.text}
+        onChange={(e) => params.setText(e.target.value)}
+        placeholder={t('sponsoring.form.text.placeholder')}
+        rows={3}
+        helperText={t('sponsoring.form.text.help')}
+      />
+      {params.error && <ErrorState message={params.error} />}
       <div className="flex gap-2">
-        <button type="submit" disabled={params.loading} className="px-4 py-2 bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded-lg font-medium transition-all border border-neon-green/50 hover:shadow-glow-green disabled:opacity-50">
+        <Button type="submit" variant="success" disabled={params.loading} loading={params.loading}>
           {params.loading ? t('common.loading') : t('sponsoring.form.submit')}
-        </button>
+        </Button>
         {params.onCancel && (
-          <button type="button" onClick={params.onCancel} className="px-4 py-2 bg-cyber-darker hover:bg-cyber-dark text-cyber-accent rounded-lg font-medium transition-all border border-neon-cyan/30">
+          <Button type="button" variant="ghost" onClick={params.onCancel}>
             {t('common.cancel')}
-          </button>
+          </Button>
         )}
       </div>
     </form>
diff --git a/components/reviewForms/ConnectRequiredCard.tsx b/components/reviewForms/ConnectRequiredCard.tsx
index eaf8e84..0bb19e2 100644
--- a/components/reviewForms/ConnectRequiredCard.tsx
+++ b/components/reviewForms/ConnectRequiredCard.tsx
@@ -1,16 +1,14 @@
 import React from 'react'
+import { Button, Card } from '@/components/ui'
 import { t } from '@/lib/i18n'
 
 export function ConnectRequiredCard(params: { message: string; onConnect: () => void }): React.ReactElement {
   return (
-    <div className="border border-neon-cyan/30 rounded-lg p-4 bg-cyber-dark">
+    <Card variant="default">
       <p className="text-cyber-accent mb-4">{params.message}</p>
-      <button
-        onClick={params.onConnect}
-        className="px-4 py-2 bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded-lg font-medium transition-all border border-neon-green/50"
-      >
+      <Button variant="success" onClick={params.onConnect}>
         {t('connect.connect')}
-      </button>
-    </div>
+      </Button>
+    </Card>
   )
 }
diff --git a/components/reviewForms/ReviewFormView.tsx b/components/reviewForms/ReviewFormView.tsx
index 7e99f09..f0dca86 100644
--- a/components/reviewForms/ReviewFormView.tsx
+++ b/components/reviewForms/ReviewFormView.tsx
@@ -1,4 +1,5 @@
 import React from 'react'
+import { Button, ErrorState } from '@/components/ui'
 import { t } from '@/lib/i18n'
 import type { ReviewFormController } from './useReviewFormController'
 
@@ -60,32 +61,29 @@ function ReviewFormFields(params: { ctrl: ReviewFormController }): React.ReactEl
 function ReviewFormActions(params: { loading: boolean; onCancel?: (() => void) | undefined }): React.ReactElement {
   return (
     <div className="flex gap-2">
-      <button
+      <Button
         type="submit"
+        variant="success"
         disabled={params.loading}
-        className="px-4 py-2 bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded-lg font-medium transition-all border border-neon-green/50 hover:shadow-glow-green disabled:opacity-50"
+        loading={params.loading}
       >
         {params.loading ? t('common.loading') : t('review.form.submit')}
-      </button>
-      {params.onCancel ? (
-        <button
+      </Button>
+      {params.onCancel && (
+        <Button
           type="button"
+          variant="ghost"
           onClick={params.onCancel}
-          className="px-4 py-2 bg-cyber-darker hover:bg-cyber-dark text-cyber-accent rounded-lg font-medium transition-all border border-neon-cyan/30"
         >
           {t('common.cancel')}
-        </button>
-      ) : null}
+        </Button>
+      )}
     </div>
   )
 }
 
 function ErrorBox({ message }: { message: string }): React.ReactElement {
-  return (
-    <div className="p-3 bg-red-900/20 border border-red-500/50 rounded text-red-400 text-sm">
-      {message}
-    </div>
-  )
+  return <ErrorState message={message} />
 }
 
 function TextInput(params: {
diff --git a/components/reviewForms/ReviewTipFormView.tsx b/components/reviewForms/ReviewTipFormView.tsx
index d1f1949..23a2e19 100644
--- a/components/reviewForms/ReviewTipFormView.tsx
+++ b/components/reviewForms/ReviewTipFormView.tsx
@@ -1,4 +1,5 @@
 import React from 'react'
+import { Button, ErrorState } from '@/components/ui'
 import { t } from '@/lib/i18n'
 import type { ReviewTipFormController } from './useReviewTipFormController'
 
@@ -57,30 +58,27 @@ function ReviewTipFormActions(params: {
 }): React.ReactElement {
   return (
     <div className="flex gap-2">
-      <button
+      <Button
         type="submit"
+        variant="success"
         disabled={params.loading}
-        className="px-4 py-2 bg-neon-green/20 hover:bg-neon-green/30 text-neon-green rounded-lg font-medium transition-all border border-neon-green/50 hover:shadow-glow-green disabled:opacity-50"
+        loading={params.loading}
       >
         {params.loading ? t('common.loading') : t('reviewTip.form.submit', { amount: params.amount })}
-      </button>
-      {params.onCancel ? (
-        <button
+      </Button>
+      {params.onCancel && (
+        <Button
           type="button"
+          variant="ghost"
           onClick={params.onCancel}
-          className="px-4 py-2 bg-cyber-darker hover:bg-cyber-dark text-cyber-accent rounded-lg font-medium transition-all border border-neon-cyan/30"
         >
           {t('common.cancel')}
-        </button>
-      ) : null}
+        </Button>
+      )}
     </div>
   )
 }
 
 function ErrorBox({ message }: { message: string }): React.ReactElement {
-  return (
-    <div className="p-3 bg-red-900/20 border border-red-500/50 rounded text-red-400 text-sm">
-      {message}
-    </div>
-  )
+  return <ErrorState message={message} />
 }
diff --git a/components/ui/MobileMenu.tsx b/components/ui/MobileMenu.tsx
index 5e0f93e..5cb7708 100644
--- a/components/ui/MobileMenu.tsx
+++ b/components/ui/MobileMenu.tsx
@@ -69,7 +69,6 @@ export function MobileMenu({ children, 'aria-label': ariaLabel }: MobileMenuProp
       />
       {isOpen && (
         <MobileMenuDrawer
-          isOpen={isOpen}
           onClose={() => setIsOpen(false)}
           ariaLabel={ariaLabel ?? 'Mobile menu'}
         >
@@ -102,44 +101,64 @@ function MobileMenuButton({
   )
 }
 
-function MobileMenuDrawer({
-  isOpen,
+function MobileMenuOverlay({ onClose }: { onClose: () => void }): React.ReactElement {
+  return (
+    <div
+      className="fixed inset-0 bg-black bg-opacity-50 z-40 md:hidden"
+      onClick={onClose}
+      aria-hidden="true"
+    />
+  )
+}
+
+function MobileMenuContent({
+  onClose,
+  ariaLabel,
+  children,
+}: {
+  onClose: () => void
+  ariaLabel: string
+  children: ReactNode
+}): React.ReactElement {
+  return (
+    <div
+      id="mobile-menu"
+      className="fixed top-0 right-0 h-full w-80 max-w-[85vw] bg-cyber-dark border-l border-neon-cyan/30 shadow-glow-cyan z-50 transform transition-transform md:hidden overflow-y-auto"
+      role="dialog"
+      aria-modal="true"
+      aria-label={ariaLabel}
+    >
+      <div className="p-4">
+        <div className="flex justify-end mb-4">
+          <button
+            onClick={onClose}
+            className="text-cyber-accent hover:text-neon-cyan text-2xl transition-colors focus:outline-none focus:ring-2 focus:ring-neon-cyan rounded"
+            aria-label="Close menu"
+          >
+            ×
+          </button>
+        </div>
+        <div className="space-y-4">{children}</div>
+      </div>
+    </div>
+  )
+}
+
+function MobileMenuDrawer({
   onClose,
   ariaLabel,
   children,
 }: {
-  isOpen: boolean
   onClose: () => void
   ariaLabel: string
   children: ReactNode
 }): React.ReactElement {
   return (
     <>
-      <div
-        className="fixed inset-0 bg-black bg-opacity-50 z-40 md:hidden"
-        onClick={onClose}
-        aria-hidden="true"
-      />
-      <div
-        id="mobile-menu"
-        className="fixed top-0 right-0 h-full w-80 max-w-[85vw] bg-cyber-dark border-l border-neon-cyan/30 shadow-glow-cyan z-50 transform transition-transform md:hidden overflow-y-auto"
-        role="dialog"
-        aria-modal="true"
-        aria-label={ariaLabel}
-      >
-        <div className="p-4">
-          <div className="flex justify-end mb-4">
-            <button
-              onClick={onClose}
-              className="text-cyber-accent hover:text-neon-cyan text-2xl transition-colors focus:outline-none focus:ring-2 focus:ring-neon-cyan rounded"
-              aria-label="Close menu"
-            >
-              ×
-            </button>
-          </div>
-          <div className="space-y-4">{children}</div>
-        </div>
-      </div>
+      <MobileMenuOverlay onClose={onClose} />
+      <MobileMenuContent onClose={onClose} ariaLabel={ariaLabel}>
+        {children}
+      </MobileMenuContent>
     </>
   )
 }
diff --git a/components/ui/Modal.tsx b/components/ui/Modal.tsx
index 5822ccf..c1db0a0 100644
--- a/components/ui/Modal.tsx
+++ b/components/ui/Modal.tsx
@@ -43,7 +43,7 @@ function ModalHeader({
   showCloseButton,
   onClose,
 }: {
-  title?: string
+  title?: string | undefined
   showCloseButton: boolean
   onClose: () => void
 }): React.ReactElement | null {
@@ -58,32 +58,28 @@ function ModalHeader({
   )
 }
 
-export function Modal({
-  children,
-  isOpen,
-  onClose,
-  title,
-  size = 'medium',
-  showCloseButton = true,
-  'aria-label': ariaLabel,
-}: ModalProps): React.ReactElement | null {
-  const modalRef = useRef<HTMLDivElement>(null)
+function useModalFocus(modalRef: React.RefObject<HTMLDivElement | null>, isOpen: boolean): void {
   const previousFocusRef = useRef<HTMLElement | null>(null)
 
   useEffect(() => {
     if (isOpen) {
-      previousFocusRef.current = document.activeElement as HTMLElement
+      const { activeElement } = document
+      if (activeElement instanceof HTMLElement) {
+        previousFocusRef.current = activeElement
+      }
       const firstFocusable = modalRef.current?.querySelector(
         'button, [href], input, select, textarea, [tabindex]:not([tabindex="-1"])'
-      ) as HTMLElement | null
-      if (firstFocusable) {
+      )
+      if (firstFocusable instanceof HTMLElement) {
         firstFocusable.focus()
       }
     } else {
       previousFocusRef.current?.focus()
     }
-  }, [isOpen])
+  }, [isOpen, modalRef])
+}
 
+function useModalKeyboard(isOpen: boolean, onClose: () => void): void {
   useEffect(() => {
     const handleEscape = (e: KeyboardEvent): void => {
       if (e.key === 'Escape' && isOpen) {
@@ -101,13 +97,17 @@ export function Modal({
       document.body.style.overflow = ''
     }
   }, [isOpen, onClose])
+}
 
-  if (!isOpen) {
-    return null
-  }
-
-  const sizeClasses = getSizeClasses(size)
-
+function ModalOverlay({
+  onClose,
+  ariaLabel,
+  children,
+}: {
+  onClose: () => void
+  ariaLabel: string | undefined
+  children: ReactNode
+}): React.ReactElement {
   return (
     <div
       className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50"
@@ -118,16 +118,70 @@ export function Modal({
       }}
       role="dialog"
       aria-modal="true"
-      aria-label={ariaLabel ?? title}
+      aria-label={ariaLabel}
     >
-      <div
-        ref={modalRef}
-        className={`bg-cyber-dark border border-neon-cyan/30 rounded-lg p-6 w-full mx-4 max-h-[90vh] overflow-y-auto shadow-glow-cyan ${sizeClasses}`}
-        onClick={(e) => e.stopPropagation()}
-      >
-        <ModalHeader title={title} showCloseButton={showCloseButton} onClose={onClose} />
-        {children}
-      </div>
+      {children}
     </div>
   )
 }
+
+function ModalContent({
+  modalRef,
+  sizeClasses,
+  title,
+  showCloseButton,
+  onClose,
+  children,
+}: {
+  modalRef: React.RefObject<HTMLDivElement | null>
+  sizeClasses: string
+  title?: string | undefined
+  showCloseButton: boolean
+  onClose: () => void
+  children: ReactNode
+}): React.ReactElement {
+  return (
+    <div
+      ref={modalRef}
+      className={`bg-cyber-dark border border-neon-cyan/30 rounded-lg p-6 w-full mx-4 max-h-[90vh] overflow-y-auto shadow-glow-cyan ${sizeClasses}`}
+      onClick={(e) => e.stopPropagation()}
+    >
+        <ModalHeader title={title} showCloseButton={showCloseButton} onClose={onClose} />
+      {children}
+    </div>
+  )
+}
+
+export function Modal({
+  children,
+  isOpen,
+  onClose,
+  title,
+  size = 'medium',
+  showCloseButton = true,
+  'aria-label': ariaLabel,
+}: ModalProps): React.ReactElement | null {
+  const modalRef = useRef<HTMLDivElement>(null)
+  useModalFocus(modalRef, isOpen)
+  useModalKeyboard(isOpen, onClose)
+
+  if (!isOpen) {
+    return null
+  }
+
+  const sizeClasses = getSizeClasses(size)
+
+  return (
+    <ModalOverlay onClose={onClose} ariaLabel={ariaLabel ?? title}>
+      <ModalContent
+        modalRef={modalRef}
+        sizeClasses={sizeClasses}
+        title={title}
+        showCloseButton={showCloseButton}
+        onClose={onClose}
+      >
+        {children}
+      </ModalContent>
+    </ModalOverlay>
+  )
+}