diff --git a/frontend/src/components/ConfirmModal.tsx b/frontend/src/components/ConfirmModal.tsx
index 2263db5..426a3d3 100644
--- a/frontend/src/components/ConfirmModal.tsx
+++ b/frontend/src/components/ConfirmModal.tsx
@@ -27,8 +27,8 @@ export default function ConfirmModal({
     switch (variant) {
       case 'danger':
         return {
-          icon: 'bg-red-100 text-red-600',
-          confirmButton: 'bg-gradient-to-r from-red-500 to-red-600 hover:shadow-lg',
+          icon: 'btn-danger',
+          confirmButton: 'btn-danger hover:shadow-lg',
         };
       case 'warning':
         return {
@@ -37,8 +37,8 @@ export default function ConfirmModal({
         };
       case 'info':
         return {
-          icon: 'bg-blue-100 text-blue-600',
-          confirmButton: 'bg-gradient-to-r from-blue-500 to-blue-600 hover:shadow-lg',
+          icon: 'btn-primary',
+          confirmButton: 'btn-primary hover:shadow-lg',
         };
     }
   };
@@ -47,10 +47,10 @@ export default function ConfirmModal({
 
   return (
     <div className="fixed inset-0 bg-black/50 backdrop-blur-sm flex items-center justify-center z-[60] p-4">
-      <div className="bg-white rounded-3xl shadow-2xl max-w-md w-full overflow-hidden animate-scale-in">
+      <div className="glass-effect rounded-3xl shadow-2xl max-w-md w-full overflow-hidden animate-scale-in">
         <div className="p-6">
           <div className="flex items-start gap-4">
-            <div className={`p-3 rounded-2xl ${styles.icon}`}>
+            <div className={`p-3 rounded-2xl ${styles.icon} text-white`}>
               <AlertTriangle className="w-6 h-6" />
             </div>
             <div className="flex-1">
diff --git a/frontend/src/components/ShoppingListModal.tsx b/frontend/src/components/ShoppingListModal.tsx
index 29f7a73..c2489c9 100644
--- a/frontend/src/components/ShoppingListModal.tsx
+++ b/frontend/src/components/ShoppingListModal.tsx
@@ -189,8 +189,8 @@ export default function ShoppingListModal({ familyId, onClose }: ShoppingListMod
   return (
     <>
       <div className="fixed inset-0 bg-black/50 backdrop-blur-sm flex items-center justify-center z-50 p-4">
-        <div className="bg-white rounded-3xl shadow-2xl max-w-2xl w-full max-h-[90vh] overflow-hidden flex flex-col">
-          <div className="bg-gradient-to-r from-green-500 to-emerald-600 p-6 flex items-center justify-between">
+        <div className="glass-effect rounded-3xl shadow-2xl max-w-2xl w-full max-h-[90vh] overflow-hidden flex flex-col">
+          <div className="btn-success p-6 flex items-center justify-between">
             <div className="flex items-center gap-3">
               <div className="p-3 bg-white/20 backdrop-blur-md rounded-2xl">
                 <ShoppingCart className="w-8 h-8 text-white" />
@@ -218,7 +218,7 @@ export default function ShoppingListModal({ familyId, onClose }: ShoppingListMod
                 />
                 <button
                   onClick={handleAddItem}
-                  className="px-6 py-3 bg-gradient-to-r from-green-500 to-green-600 text-white rounded-2xl hover:shadow-lg transition-all font-semibold flex items-center gap-2"
+                  className="px-6 py-3 btn-success text-white rounded-2xl hover:shadow-lg transition-all font-semibold flex items-center gap-2"
                 >
                   <Plus className="w-5 h-5" />
                   <span className="hidden sm:inline">{t('common.add')}</span>
@@ -342,14 +342,14 @@ export default function ShoppingListModal({ familyId, onClose }: ShoppingListMod
               <div className="flex gap-3">
                 <button
                   onClick={handleMarkAllPurchased}
-                  className="flex-1 flex items-center justify-center gap-2 px-4 py-3 bg-gradient-to-r from-green-500 to-green-600 text-white rounded-2xl hover:shadow-lg transition-all font-semibold"
+                  className="flex-1 flex items-center justify-center gap-2 px-4 py-3 btn-success text-white rounded-2xl hover:shadow-lg transition-all font-semibold"
                 >
                   <Check className="w-5 h-5" />
                   {t('shopping.allPurchased')}
                 </button>
                 <button
                   onClick={handleClearAll}
-                  className="flex-1 flex items-center justify-center gap-2 px-4 py-3 bg-gradient-to-r from-red-500 to-red-600 text-white rounded-2xl hover:shadow-lg transition-all font-semibold"
+                  className="flex-1 flex items-center justify-center gap-2 px-4 py-3 btn-danger text-white rounded-2xl hover:shadow-lg transition-all font-semibold"
                 >
                   <Trash2 className="w-5 h-5" />
                   {t('shopping.clear')}
diff --git a/frontend/src/i18n/locales/en.json b/frontend/src/i18n/locales/en.json
index e989cfa..8284513 100644
--- a/frontend/src/i18n/locales/en.json
+++ b/frontend/src/i18n/locales/en.json
@@ -159,6 +159,14 @@
     "leaveConfirm": "Are you sure you want to leave the family?",
     "leaving": "Leaving...",
     "leaveError": "Error leaving family",
-    "renameError": "Error renaming family"
+    "renameError": "Error renaming family",
+    "themes": {
+      "light": "Light",
+      "dark": "Dark",
+      "sunset": "Sunset",
+      "ocean": "Ocean",
+      "forest": "Forest",
+      "purple": "Purple"
+    }
   }
 }
diff --git a/frontend/src/i18n/locales/ru.json b/frontend/src/i18n/locales/ru.json
index 0410cf6..bbc31ea 100644
--- a/frontend/src/i18n/locales/ru.json
+++ b/frontend/src/i18n/locales/ru.json
@@ -159,6 +159,14 @@
     "leaveConfirm": "Вы уверены, что хотите покинуть семью?",
     "leaving": "Выход...",
     "leaveError": "Ошибка при выходе из семьи",
-    "renameError": "Ошибка при переименовании семьи"
+    "renameError": "Ошибка при переименовании семьи",
+    "themes": {
+      "light": "Светлая",
+      "dark": "Тёмная",
+      "sunset": "Закат",
+      "ocean": "Океан",
+      "forest": "Лес",
+      "purple": "Фиолетовая"
+    }
   }
 }
diff --git a/frontend/src/index.css b/frontend/src/index.css
index d954a6c..28cde43 100644
--- a/frontend/src/index.css
+++ b/frontend/src/index.css
@@ -7,14 +7,32 @@
   --glass-bg: rgba(255, 255, 255, 0.8);
   --text-primary: #1f2937;
   --text-secondary: #6b7280;
+  --category-from: #8b5cf6;
+  --category-to: #3b82f6;
+  --btn-primary-from: #8b5cf6;
+  --btn-primary-to: #6366f1;
+  --btn-success-from: #22c55e;
+  --btn-success-to: #16a34a;
+  --btn-danger-from: #ef4444;
+  --btn-danger-to: #ec4899;
+  --card-bg: rgba(255, 255, 255, 0.8);
 }
 
 [data-theme="dark"] {
-  --gradient-start: #1f2937;
-  --gradient-end: #111827;
-  --glass-bg: rgba(31, 41, 55, 0.9);
+  --gradient-start: #000000;
+  --gradient-end: #000000;
+  --glass-bg: rgba(17, 17, 17, 0.95);
   --text-primary: #f9fafb;
   --text-secondary: #d1d5db;
+  --category-from: #6366f1;
+  --category-to: #8b5cf6;
+  --btn-primary-from: #6366f1;
+  --btn-primary-to: #8b5cf6;
+  --btn-success-from: #059669;
+  --btn-success-to: #10b981;
+  --btn-danger-from: #dc2626;
+  --btn-danger-to: #be185d;
+  --card-bg: rgba(31, 31, 31, 0.9);
 }
 
 [data-theme="sunset"] {
@@ -23,6 +41,15 @@
   --glass-bg: rgba(255, 255, 255, 0.85);
   --text-primary: #1f2937;
   --text-secondary: #6b7280;
+  --category-from: #f97316;
+  --category-to: #ec4899;
+  --btn-primary-from: #f97316;
+  --btn-primary-to: #ea580c;
+  --btn-success-from: #22c55e;
+  --btn-success-to: #16a34a;
+  --btn-danger-from: #ef4444;
+  --btn-danger-to: #dc2626;
+  --card-bg: rgba(255, 255, 255, 0.85);
 }
 
 [data-theme="ocean"] {
@@ -31,6 +58,15 @@
   --glass-bg: rgba(255, 255, 255, 0.85);
   --text-primary: #1f2937;
   --text-secondary: #6b7280;
+  --category-from: #3b82f6;
+  --category-to: #06b6d4;
+  --btn-primary-from: #3b82f6;
+  --btn-primary-to: #2563eb;
+  --btn-success-from: #22c55e;
+  --btn-success-to: #16a34a;
+  --btn-danger-from: #ef4444;
+  --btn-danger-to: #dc2626;
+  --card-bg: rgba(255, 255, 255, 0.85);
 }
 
 [data-theme="forest"] {
@@ -39,6 +75,15 @@
   --glass-bg: rgba(255, 255, 255, 0.85);
   --text-primary: #1f2937;
   --text-secondary: #6b7280;
+  --category-from: #22c55e;
+  --category-to: #14b8a6;
+  --btn-primary-from: #22c55e;
+  --btn-primary-to: #16a34a;
+  --btn-success-from: #22c55e;
+  --btn-success-to: #16a34a;
+  --btn-danger-from: #ef4444;
+  --btn-danger-to: #dc2626;
+  --card-bg: rgba(255, 255, 255, 0.85);
 }
 
 [data-theme="purple"] {
@@ -47,6 +92,15 @@
   --glass-bg: rgba(255, 255, 255, 0.85);
   --text-primary: #1f2937;
   --text-secondary: #6b7280;
+  --category-from: #8b5cf6;
+  --category-to: #ec4899;
+  --btn-primary-from: #8b5cf6;
+  --btn-primary-to: #7c3aed;
+  --btn-success-from: #22c55e;
+  --btn-success-to: #16a34a;
+  --btn-danger-from: #ef4444;
+  --btn-danger-to: #dc2626;
+  --card-bg: rgba(255, 255, 255, 0.85);
 }
 
 .gradient-bg {
@@ -67,10 +121,66 @@
 }
 
 .glass-effect {
-  background: rgb(255 255 255 / 0.8);
+  background: var(--glass-bg);
   backdrop-filter: blur(12px);
 }
 
+.category-icon {
+  background: linear-gradient(135deg, var(--category-from) 0%, var(--category-to) 100%);
+}
+
+.btn-primary {
+  background: linear-gradient(135deg, var(--btn-primary-from) 0%, var(--btn-primary-to) 100%);
+}
+
+.btn-success {
+  background: linear-gradient(135deg, var(--btn-success-from) 0%, var(--btn-success-to) 100%);
+}
+
+.btn-danger {
+  background: linear-gradient(135deg, var(--btn-danger-from) 0%, var(--btn-danger-to) 100%);
+}
+
+[data-theme="dark"] .glass-effect {
+  color: var(--text-primary);
+}
+
+[data-theme="dark"] .text-gray-800,
+[data-theme="dark"] .text-gray-900 {
+  color: var(--text-primary);
+}
+
+[data-theme="dark"] .text-gray-600,
+[data-theme="dark"] .text-gray-500 {
+  color: var(--text-secondary);
+}
+
+[data-theme="dark"] .bg-gray-100,
+[data-theme="dark"] .bg-gray-50 {
+  background-color: rgba(55, 55, 55, 0.5);
+}
+
+[data-theme="dark"] .bg-gray-200 {
+  background-color: rgba(75, 75, 75, 0.5);
+}
+
+[data-theme="dark"] .border-gray-200,
+[data-theme="dark"] .border-gray-300 {
+  border-color: rgba(75, 75, 75, 0.8);
+}
+
+[data-theme="dark"] input,
+[data-theme="dark"] textarea {
+  background-color: rgba(40, 40, 40, 0.9);
+  color: var(--text-primary);
+  border-color: rgba(75, 75, 75, 0.8);
+}
+
+[data-theme="dark"] input::placeholder,
+[data-theme="dark"] textarea::placeholder {
+  color: var(--text-secondary);
+}
+
 .animate-fadeIn {
   animation: fadeIn 0.2s ease-in-out;
 }
diff --git a/frontend/src/pages/AdminPanel.tsx b/frontend/src/pages/AdminPanel.tsx
index 643eee4..a2248ce 100644
--- a/frontend/src/pages/AdminPanel.tsx
+++ b/frontend/src/pages/AdminPanel.tsx
@@ -81,7 +81,7 @@ export default function AdminPanel() {
         <div className="max-w-md w-full">
           <div className="glass-effect rounded-2xl shadow-2xl p-6 sm:p-8 text-center">
             <div className="flex items-center justify-center mb-6">
-              <div className="p-4 bg-linear-to-br from-red-500 to-orange-500 text-white rounded-2xl">
+              <div className="p-4 btn-danger text-white rounded-2xl">
                 <Shield className="w-10 h-10 sm:w-12 sm:h-12" />
               </div>
             </div>
@@ -137,7 +137,7 @@ export default function AdminPanel() {
 
         <div className="glass-effect rounded-3xl shadow-xl p-6 sm:p-10 mb-6 max-w-2xl mx-auto">
           <div className="flex items-center justify-center gap-3 mb-8">
-            <div className="p-3 bg-linear-to-br from-green-500 to-green-600 rounded-2xl">
+            <div className="p-3 btn-success rounded-2xl">
               <Plus className="w-8 h-8 text-white" />
             </div>
             <h2 className="text-2xl sm:text-3xl font-bold text-gray-800">
@@ -174,7 +174,7 @@ export default function AdminPanel() {
             </div>
             <button
               onClick={handleCreateFamily}
-              className="w-full flex items-center justify-center gap-2 px-6 py-4 bg-linear-to-r from-green-500 to-green-600 text-white rounded-2xl hover:shadow-xl transition-all duration-300 font-semibold text-lg"
+              className="w-full flex items-center justify-center gap-2 px-6 py-4 btn-success text-white rounded-2xl hover:shadow-xl transition-all duration-300 font-semibold text-lg"
             >
               <Plus className="w-6 h-6" />
               {t('admin.createButton')}
@@ -184,7 +184,7 @@ export default function AdminPanel() {
 
         <div className="glass-effect rounded-3xl shadow-xl p-6 sm:p-10 max-w-3xl mx-auto">
           <div className="flex items-center justify-center gap-3 mb-8">
-            <div className="p-3 bg-linear-to-br from-purple-500 to-blue-500 rounded-2xl">
+            <div className="p-3 category-icon rounded-2xl">
               <Users className="w-8 h-8 text-white" />
             </div>
             <h2 className="text-2xl sm:text-3xl font-bold text-gray-800">
@@ -194,8 +194,8 @@ export default function AdminPanel() {
 
           {families.length === 0 ? (
             <div className="text-center py-16 sm:py-20">
-              <div className="inline-flex p-6 bg-linear-to-br from-purple-100 to-blue-100 rounded-3xl mb-6">
-                <Users className="w-20 h-20 text-purple-400" />
+              <div className="inline-flex p-6 bg-gray-100 rounded-3xl mb-6">
+                <Users className="w-20 h-20 text-gray-400" />
               </div>
               <p className="text-gray-600 text-lg sm:text-xl mb-2 font-semibold">
                 {t('admin.noFamilies')}
@@ -209,10 +209,10 @@ export default function AdminPanel() {
               {families.map((family) => (
                 <div
                   key={family.id}
-                  className="flex flex-col sm:flex-row justify-between items-start sm:items-center gap-3 p-5 bg-linear-to-r from-purple-50 to-blue-50 rounded-2xl border-2 border-purple-200 card-hover"
+                  className="flex flex-col sm:flex-row justify-between items-start sm:items-center gap-3 p-5 bg-gray-50 rounded-2xl border-2 border-gray-200 card-hover"
                 >
                   <div className="flex items-center gap-3">
-                    <div className="p-3 bg-linear-to-br from-purple-500 to-blue-500 text-white rounded-xl shadow-md">
+                    <div className="p-3 category-icon text-white rounded-xl shadow-md">
                       <Users className="w-6 h-6" />
                     </div>
                     <span className="text-lg sm:text-xl font-bold text-gray-900">
@@ -221,7 +221,7 @@ export default function AdminPanel() {
                   </div>
                   <button
                     onClick={() => handleDeleteFamily(family.id)}
-                    className="w-full sm:w-auto flex items-center justify-center gap-2 px-5 py-3 bg-red-500 hover:bg-red-600 text-white rounded-xl transition-all font-semibold shadow-md hover:shadow-lg"
+                    className="w-full sm:w-auto flex items-center justify-center gap-2 px-5 py-3 btn-danger text-white rounded-xl transition-all font-semibold shadow-md hover:shadow-lg"
                   >
                     <Trash2 className="w-5 h-5" />
                     {t('common.delete')}
diff --git a/frontend/src/pages/FamilyView.tsx b/frontend/src/pages/FamilyView.tsx
index 3c355b6..ece86de 100644
--- a/frontend/src/pages/FamilyView.tsx
+++ b/frontend/src/pages/FamilyView.tsx
@@ -308,7 +308,7 @@ export default function FamilyView() {
               </div>
               <button
                 onClick={() => setShowShoppingList(true)}
-                className="w-full flex items-center justify-center gap-2 px-6 py-3 bg-gradient-to-r from-green-500 to-emerald-600 text-white rounded-2xl hover:shadow-xl transition-all duration-300 font-semibold"
+                className="w-full flex items-center justify-center gap-2 px-6 py-3 btn-success text-white rounded-2xl hover:shadow-xl transition-all duration-300 font-semibold"
               >
                 <ShoppingCart className="w-5 h-5" />
                 {t('family.shoppingList')}
@@ -339,7 +339,7 @@ export default function FamilyView() {
               >
                 <div className="flex items-center justify-between gap-3 mb-4">
                   <div className="flex items-center gap-3">
-                    <div className="p-2 bg-linear-to-br from-purple-500 to-blue-500 text-white rounded-xl shadow-lg">
+                    <div className="p-2 category-icon text-white rounded-xl shadow-lg">
                       <Tag className="w-6 h-6" />
                     </div>
                     <h2 className="text-xl sm:text-2xl font-bold text-gray-900">
@@ -350,7 +350,7 @@ export default function FamilyView() {
                   {showAddExpense !== category.id && (
                     <button
                       onClick={() => setShowAddExpense(category.id)}
-                      className="flex items-center gap-2 px-4 py-2 bg-linear-to-r from-red-500 to-pink-500 text-white rounded-xl hover:shadow-lg transition-all duration-300 font-semibold whitespace-nowrap text-sm"
+                      className="flex items-center gap-2 px-4 py-2 btn-danger text-white rounded-xl hover:shadow-lg transition-all duration-300 font-semibold whitespace-nowrap text-sm"
                     >
                       <TrendingDown className="w-4 h-4" />
                       <span className="hidden sm:inline">{t('category.addExpense')}</span>
@@ -407,7 +407,7 @@ export default function FamilyView() {
                 </div>
 
                 {showHistory === category.id && (
-                  <div className="mt-4 bg-linear-to-br from-blue-50 to-purple-50 p-4 rounded-2xl border-2 border-blue-200">
+                  <div className="mt-4 glass-effect p-4 rounded-2xl border-2 border-gray-200">
                     <div className="flex items-center justify-between mb-4">
                       <h3 className="font-semibold text-gray-800 text-lg flex items-center gap-2">
                         <History className="w-5 h-5" />
@@ -458,7 +458,7 @@ export default function FamilyView() {
                 )}
 
                 {showAddExpense === category.id && (
-                  <div className="bg-linear-to-br from-purple-50 to-blue-50 p-6 rounded-2xl border-2 border-purple-200">
+                  <div className="glass-effect p-6 rounded-2xl border-2 border-gray-200 mt-4">
                     <h3 className="font-semibold text-gray-800 mb-4 text-center">
                       {t('expense.addTitle')}
                     </h3>
@@ -490,7 +490,7 @@ export default function FamilyView() {
                       <div className="flex gap-3">
                         <button
                           onClick={() => handleAddExpense(category.id)}
-                          className="flex-1 flex items-center justify-center gap-2 px-5 py-3 bg-linear-to-r from-green-500 to-green-600 text-white rounded-2xl hover:shadow-xl transition-all font-semibold"
+                          className="flex-1 flex items-center justify-center gap-2 px-5 py-3 btn-success text-white rounded-2xl hover:shadow-xl transition-all font-semibold"
                         >
                           <Plus className="w-5 h-5" />
                           {t('common.add')}
@@ -512,7 +512,7 @@ export default function FamilyView() {
 
         <div className="glass-effect rounded-3xl shadow-xl p-6 sm:p-8 max-w-3xl mx-auto">
           <div className="flex items-center justify-center gap-3 mb-8">
-            <div className="p-3 bg-linear-to-br from-purple-500 to-blue-500 rounded-2xl">
+            <div className="p-3 category-icon rounded-2xl">
               <DollarSign className="w-8 h-8 text-white" />
             </div>
             <h2 className="text-2xl sm:text-3xl font-bold text-gray-800">
@@ -521,7 +521,7 @@ export default function FamilyView() {
           </div>
 
           {showAddCategory ? (
-            <div className="mb-8 p-6 bg-linear-to-br from-purple-50 to-blue-50 rounded-2xl border-2 border-purple-200">
+            <div className="mb-8 p-6 glass-effect rounded-2xl border-2 border-gray-200">
               <h3 className="font-bold text-gray-800 mb-5 text-center text-lg">
                 {t('category.newCategory')}
               </h3>
@@ -543,7 +543,7 @@ export default function FamilyView() {
                 <div className="flex gap-3">
                   <button
                     onClick={handleAddCategory}
-                    className="flex-1 flex items-center justify-center gap-2 px-6 py-4 bg-linear-to-r from-green-500 to-green-600 text-white rounded-2xl hover:shadow-xl transition-all font-semibold"
+                    className="flex-1 flex items-center justify-center gap-2 px-6 py-4 btn-success text-white rounded-2xl hover:shadow-xl transition-all font-semibold"
                   >
                     <Plus className="w-5 h-5" />
                     {t('common.create')}
@@ -560,7 +560,7 @@ export default function FamilyView() {
           ) : (
             <button
               onClick={() => setShowAddCategory(true)}
-              className="w-full flex items-center justify-center gap-2 px-6 py-4 bg-linear-to-r from-purple-600 to-blue-600 text-white rounded-2xl hover:shadow-xl transition-all duration-300 font-semibold"
+              className="w-full flex items-center justify-center gap-2 px-6 py-4 btn-primary text-white rounded-2xl hover:shadow-xl transition-all duration-300 font-semibold"
             >
               <Plus className="w-5 h-5" />
               {t('category.addCategory')}
@@ -578,10 +578,10 @@ export default function FamilyView() {
 
       {showInviteModal && (
         <div className="fixed inset-0 bg-black/60 backdrop-blur-sm flex items-center justify-center z-50 p-4">
-          <div className="bg-white rounded-3xl shadow-2xl w-full max-w-md p-6 sm:p-8">
+          <div className="glass-effect rounded-3xl shadow-2xl w-full max-w-md p-6 sm:p-8">
             <div className="flex items-center justify-between mb-6">
               <div className="flex items-center gap-3">
-                <div className="p-3 bg-gradient-to-br from-purple-500 to-blue-500 rounded-2xl">
+                <div className="p-3 category-icon rounded-2xl">
                   <UserPlus className="w-6 h-6 text-white" />
                 </div>
                 <h2 className="text-xl font-bold text-gray-800">{t('invite.title')}</h2>
@@ -602,7 +602,7 @@ export default function FamilyView() {
                 <button
                   onClick={handleCreateInviteLink}
                   disabled={inviteLoading}
-                  className="w-full flex items-center justify-center gap-2 px-6 py-4 bg-gradient-to-r from-purple-600 to-blue-600 text-white rounded-2xl hover:shadow-xl transition-all font-semibold disabled:opacity-50"
+                  className="w-full flex items-center justify-center gap-2 px-6 py-4 btn-primary text-white rounded-2xl hover:shadow-xl transition-all font-semibold disabled:opacity-50"
                 >
                   {inviteLoading ? (
                     <>
@@ -631,8 +631,8 @@ export default function FamilyView() {
                   onClick={handleCopyInviteLink}
                   className={`w-full flex items-center justify-center gap-2 px-6 py-4 rounded-2xl transition-all font-semibold ${
                     copied
-                      ? 'bg-green-500 text-white'
-                      : 'bg-gradient-to-r from-purple-600 to-blue-600 text-white hover:shadow-xl'
+                      ? 'btn-success text-white'
+                      : 'btn-primary text-white hover:shadow-xl'
                   }`}
                 >
                   {copied ? (
diff --git a/frontend/src/pages/InvitePage.tsx b/frontend/src/pages/InvitePage.tsx
index ec84b38..a8827ae 100644
--- a/frontend/src/pages/InvitePage.tsx
+++ b/frontend/src/pages/InvitePage.tsx
@@ -109,15 +109,15 @@ export default function InvitePage() {
   if (error) {
     return (
       <div className="min-h-screen flex items-center justify-center gradient-bg px-4">
-        <div className="bg-white rounded-3xl shadow-2xl p-8 max-w-md w-full text-center">
-          <div className="p-4 bg-red-100 rounded-2xl inline-block mb-6">
-            <AlertCircle className="w-12 h-12 text-red-500" />
+        <div className="glass-effect rounded-3xl shadow-2xl p-8 max-w-md w-full text-center">
+          <div className="p-4 btn-danger rounded-2xl inline-block mb-6">
+            <AlertCircle className="w-12 h-12 text-white" />
           </div>
           <h1 className="text-2xl font-bold text-gray-800 mb-4">{t('common.error')}</h1>
           <p className="text-gray-600 mb-6">{error}</p>
           <button
             onClick={() => navigate('/')}
-            className="px-6 py-3 bg-gradient-to-r from-purple-600 to-blue-600 text-white rounded-2xl font-semibold hover:shadow-xl transition-all"
+            className="px-6 py-3 btn-primary text-white rounded-2xl font-semibold hover:shadow-xl transition-all"
           >
             {t('common.toHome')}
           </button>
@@ -128,14 +128,14 @@ export default function InvitePage() {
 
   return (
     <div className="min-h-screen flex items-center justify-center gradient-bg px-4">
-      <div className="bg-white rounded-3xl shadow-2xl p-8 max-w-md w-full text-center">
-        <div className="p-4 bg-gradient-to-br from-purple-500 to-blue-500 rounded-2xl inline-block mb-6">
+      <div className="glass-effect rounded-3xl shadow-2xl p-8 max-w-md w-full text-center">
+        <div className="p-4 category-icon rounded-2xl inline-block mb-6">
           <Users className="w-12 h-12 text-white" />
         </div>
         <h1 className="text-2xl font-bold text-gray-800 mb-2">
           {t('invite.pageTitle')}
         </h1>
-        <p className="text-3xl font-bold text-purple-600 mb-6">
+        <p className="text-3xl font-bold text-gray-800 mb-6">
           {familyName}
         </p>
         <p className="text-gray-600 mb-8">
@@ -143,7 +143,7 @@ export default function InvitePage() {
         </p>
         <button
           onClick={handleGoogleLogin}
-          className="w-full flex items-center justify-center gap-3 px-6 py-4 bg-gradient-to-r from-purple-600 to-blue-600 text-white rounded-2xl font-semibold hover:shadow-xl transition-all"
+          className="w-full flex items-center justify-center gap-3 px-6 py-4 btn-primary text-white rounded-2xl font-semibold hover:shadow-xl transition-all"
         >
           <UserPlus className="w-5 h-5" />
           {t('invite.loginAndJoin')}
diff --git a/frontend/src/pages/Login.tsx b/frontend/src/pages/Login.tsx
index d8be09b..70f644d 100644
--- a/frontend/src/pages/Login.tsx
+++ b/frontend/src/pages/Login.tsx
@@ -27,7 +27,7 @@ export default function Login() {
       <div className="w-full max-w-md">
         <div className="glass-effect rounded-3xl shadow-2xl p-8 sm:p-10">
           <div className="flex flex-col items-center text-center mb-8">
-            <div className="p-4 bg-linear-to-br from-purple-500 to-blue-500 text-white rounded-2xl mb-4 shadow-lg">
+            <div className="p-4 category-icon text-white rounded-2xl mb-4 shadow-lg">
               <Wallet className="w-12 h-12" />
             </div>
             <h1 className="text-3xl sm:text-4xl font-bold text-gray-900 mb-2">
diff --git a/frontend/src/pages/NoFamily.tsx b/frontend/src/pages/NoFamily.tsx
index 418be37..1a4c5d7 100644
--- a/frontend/src/pages/NoFamily.tsx
+++ b/frontend/src/pages/NoFamily.tsx
@@ -118,7 +118,7 @@ export default function NoFamily() {
       <div className="w-full max-w-md">
         <div className="glass-effect rounded-3xl shadow-2xl p-8 sm:p-10">
           <div className="flex flex-col items-center text-center mb-6">
-            <div className="p-4 bg-linear-to-br from-purple-500 to-blue-500 text-white rounded-2xl mb-4 shadow-lg">
+            <div className="p-4 category-icon text-white rounded-2xl mb-4 shadow-lg">
               <Users className="w-12 h-12" />
             </div>
             <h1 className="text-2xl sm:text-3xl font-bold text-gray-900 mb-2">
@@ -186,7 +186,7 @@ export default function NoFamily() {
               <button
                 type="submit"
                 disabled={loading || !familyName.trim()}
-                className="w-full flex items-center justify-center gap-2 px-6 py-4 bg-linear-to-r from-purple-600 to-blue-600 text-white rounded-2xl hover:shadow-xl transition-all duration-300 font-semibold disabled:opacity-50 disabled:cursor-not-allowed"
+                className="w-full flex items-center justify-center gap-2 px-6 py-4 btn-primary text-white rounded-2xl hover:shadow-xl transition-all duration-300 font-semibold disabled:opacity-50 disabled:cursor-not-allowed"
               >
                 {loading ? (
                   <Loader2 className="w-5 h-5 animate-spin" />
diff --git a/frontend/src/pages/Profile.tsx b/frontend/src/pages/Profile.tsx
index 9aa8ca2..8032ade 100644
--- a/frontend/src/pages/Profile.tsx
+++ b/frontend/src/pages/Profile.tsx
@@ -20,13 +20,13 @@ import {
   X,
 } from 'lucide-react';
 
-const THEMES: { id: Theme; name: string; gradient: string }[] = [
-  { id: 'light', name: 'Light', gradient: 'bg-gradient-to-r from-gray-100 to-gray-200' },
-  { id: 'dark', name: 'Dark', gradient: 'bg-gradient-to-r from-gray-800 to-gray-900' },
-  { id: 'sunset', name: 'Sunset', gradient: 'bg-gradient-to-r from-orange-400 to-pink-500' },
-  { id: 'ocean', name: 'Ocean', gradient: 'bg-gradient-to-r from-blue-400 to-cyan-500' },
-  { id: 'forest', name: 'Forest', gradient: 'bg-gradient-to-r from-green-400 to-teal-500' },
-  { id: 'purple', name: 'Purple', gradient: 'bg-gradient-to-r from-purple-500 to-pink-500' },
+const THEMES: { id: Theme; gradient: string }[] = [
+  { id: 'light', gradient: 'bg-gradient-to-r from-gray-100 to-gray-200' },
+  { id: 'dark', gradient: 'bg-gradient-to-r from-black to-gray-900' },
+  { id: 'sunset', gradient: 'bg-gradient-to-r from-orange-400 to-pink-500' },
+  { id: 'ocean', gradient: 'bg-gradient-to-r from-blue-400 to-cyan-500' },
+  { id: 'forest', gradient: 'bg-gradient-to-r from-green-400 to-teal-500' },
+  { id: 'purple', gradient: 'bg-gradient-to-r from-purple-500 to-pink-500' },
 ];
 
 export default function Profile() {
@@ -140,7 +140,7 @@ export default function Profile() {
         <div className="space-y-6">
           <div className="glass-effect rounded-2xl shadow-lg p-6">
             <div className="flex items-center gap-3 mb-4">
-              <div className="p-2 bg-gradient-to-br from-blue-500 to-purple-500 text-white rounded-xl">
+              <div className="p-2 category-icon text-white rounded-xl">
                 <UserIcon className="w-6 h-6" />
               </div>
               <h2 className="text-xl font-bold text-gray-800">{t('profile.info')}</h2>
@@ -160,7 +160,7 @@ export default function Profile() {
           {selectedFamily && (
             <div className="glass-effect rounded-2xl shadow-lg p-6">
               <div className="flex items-center gap-3 mb-4">
-                <div className="p-2 bg-gradient-to-br from-green-500 to-teal-500 text-white rounded-xl">
+                <div className="p-2 btn-success text-white rounded-xl">
                   <Users className="w-6 h-6" />
                 </div>
                 <h2 className="text-xl font-bold text-gray-800">{t('profile.family')}</h2>
@@ -220,7 +220,7 @@ export default function Profile() {
                         className={`flex items-center justify-between p-3 rounded-xl ${member.id === user?.id ? 'bg-purple-50 border border-purple-200' : 'bg-gray-50'}`}
                       >
                         <div className="flex items-center gap-2">
-                          <div className="w-8 h-8 bg-gradient-to-br from-purple-400 to-blue-400 rounded-full flex items-center justify-center text-white text-sm font-medium">
+                          <div className="w-8 h-8 category-icon rounded-full flex items-center justify-center text-white text-sm font-medium">
                             {(member.username || member.email || '?')[0].toUpperCase()}
                           </div>
                           <span className="font-medium text-gray-800">
@@ -247,7 +247,7 @@ export default function Profile() {
 
           <div className="glass-effect rounded-2xl shadow-lg p-6">
             <div className="flex items-center gap-3 mb-4">
-              <div className="p-2 bg-gradient-to-br from-purple-500 to-pink-500 text-white rounded-xl">
+              <div className="p-2 btn-primary text-white rounded-xl">
                 <Settings className="w-6 h-6" />
               </div>
               <h2 className="text-xl font-bold text-gray-800">{t('profile.settings')}</h2>
@@ -264,7 +264,7 @@ export default function Profile() {
                     onClick={() => handleLocaleChange('ru')}
                     className={`flex-1 py-3 px-4 rounded-xl font-medium transition-all ${
                       preferences.locale === 'ru'
-                        ? 'bg-purple-500 text-white shadow-lg'
+                        ? 'btn-primary text-white shadow-lg'
                         : 'bg-gray-100 text-gray-700 hover:bg-gray-200'
                     }`}
                   >
@@ -276,7 +276,7 @@ export default function Profile() {
                     onClick={() => handleLocaleChange('en')}
                     className={`flex-1 py-3 px-4 rounded-xl font-medium transition-all ${
                       preferences.locale === 'en'
-                        ? 'bg-purple-500 text-white shadow-lg'
+                        ? 'btn-primary text-white shadow-lg'
                         : 'bg-gray-100 text-gray-700 hover:bg-gray-200'
                     }`}
                   >
@@ -304,7 +304,7 @@ export default function Profile() {
                       }`}
                     >
                       <div className={`h-12 rounded-lg ${theme.gradient}`} />
-                      <span className="text-xs text-gray-600 mt-1 block">{theme.name}</span>
+                      <span className="text-xs text-gray-600 mt-1 block">{t(`profile.themes.${theme.id}`)}</span>
                       {preferences.theme === theme.id && (
                         <div className="absolute top-2 right-2 w-5 h-5 bg-white rounded-full flex items-center justify-center shadow">
                           <Check className="w-3 h-3 text-purple-600" />
@@ -320,7 +320,7 @@ export default function Profile() {
           {selectedFamily && (
             <div className="glass-effect rounded-2xl shadow-lg p-6 border-2 border-red-200">
               <div className="flex items-center gap-3 mb-4">
-                <div className="p-2 bg-gradient-to-br from-red-500 to-orange-500 text-white rounded-xl">
+                <div className="p-2 btn-danger text-white rounded-xl">
                   <AlertTriangle className="w-6 h-6" />
                 </div>
                 <h2 className="text-xl font-bold text-gray-800">{t('profile.dangerZone')}</h2>
@@ -331,7 +331,7 @@ export default function Profile() {
               <button
                 onClick={handleLeaveFamily}
                 disabled={leavingFamily}
-                className="w-full flex items-center justify-center gap-2 px-6 py-3 bg-red-500 hover:bg-red-600 text-white rounded-xl transition-all font-semibold disabled:opacity-50"
+                className="w-full flex items-center justify-center gap-2 px-6 py-3 btn-danger text-white rounded-xl transition-all font-semibold disabled:opacity-50"
               >
                 {leavingFamily ? (
                   <>