Index: chapterx-frontend/src/store/authStore.ts
===================================================================
--- chapterx-frontend/src/store/authStore.ts	(revision b62cefc14094ca5ac7154f7d48797a1e6c444935)
+++ chapterx-frontend/src/store/authStore.ts	(revision b62cefc14094ca5ac7154f7d48797a1e6c444935)
@@ -0,0 +1,122 @@
+import { create } from 'zustand'
+import { persist } from 'zustand/middleware'
+import { User, UserRole } from '../types'
+import { mockUsers } from '../data/mockData'
+import axios from 'axios'
+
+const API_BASE = 'https://localhost:7125/api'
+
+interface AuthStore {
+  currentUser: User | null
+  token: string | null
+  showMatureContent: boolean
+  allUsers: User[]
+  login: (emailOrUsername: string, password: string) => Promise<void>
+  logout: () => void
+  register: (data: { username: string; email: string; name: string; surname: string; password: string }, role: 'regular' | 'writer') => Promise<void>
+  switchUser: (userId: number) => void
+  setShowMatureContent: (show: boolean) => void
+  updateUserRole: (userId: number, role: UserRole) => void
+  addUser: (user: User) => void
+}
+
+export const useAuthStore = create<AuthStore>()(
+  persist(
+    (set, get) => ({
+      currentUser: null,
+      token: null,
+      showMatureContent: true,
+      allUsers: [...mockUsers],
+
+      login: async (emailOrUsername, password) => {
+        // Try backend first
+        try {
+          const email = emailOrUsername.includes('@')
+            ? emailOrUsername
+            : get().allUsers.find(u => u.username === emailOrUsername)?.email || emailOrUsername
+          const res = await axios.post(`${API_BASE}/auth/login`, { email, password }, { timeout: 3000 })
+          const { token, userId, username } = res.data
+          const user = get().allUsers.find(u => u.user_id === userId) ||
+            get().allUsers.find(u => u.username === username) || {
+              user_id: userId,
+              username,
+              email,
+              name: username,
+              surname: '',
+              role: 'regular' as const,
+              created_at: new Date().toISOString(),
+              follower_count: 0,
+              following_count: 0,
+            }
+          set({ currentUser: user, token })
+          return
+        } catch {
+          // Fall through to mock login
+        }
+
+        // Fallback to mock
+        const user = get().allUsers.find(
+          u => u.username === emailOrUsername || u.email === emailOrUsername
+        )
+        if (!user) throw new Error('User not found. Try using a quick-login option.')
+        set({ currentUser: user, token: 'mock-token' })
+      },
+
+      logout: () => set({ currentUser: null, token: null }),
+
+      register: async (data, role) => {
+        // Try backend first
+        try {
+          await axios.post(`${API_BASE}/auth/register`, data, { timeout: 3000 })
+        } catch {
+          // Fall through to mock register
+        }
+
+        const newUser: User = {
+          user_id: Date.now(),
+          ...data,
+          role,
+          created_at: new Date().toISOString(),
+          follower_count: 0,
+          following_count: 0,
+        }
+        set(state => ({
+          allUsers: [...state.allUsers, newUser],
+          currentUser: newUser,
+          token: 'mock-token',
+        }))
+      },
+
+      switchUser: (userId: number) => {
+        if (userId === 0) {
+          set({ currentUser: null, token: null })
+          return
+        }
+        const user = get().allUsers.find(u => u.user_id === userId)
+        if (user) set({ currentUser: user, token: 'mock-token' })
+      },
+
+      setShowMatureContent: (show: boolean) => set({ showMatureContent: show }),
+
+      updateUserRole: (userId: number, role: UserRole) =>
+        set(state => ({
+          allUsers: state.allUsers.map(u => (u.user_id === userId ? { ...u, role } : u)),
+          currentUser:
+            state.currentUser?.user_id === userId
+              ? { ...state.currentUser, role }
+              : state.currentUser,
+        })),
+
+      addUser: (user: User) =>
+        set(state => ({ allUsers: [...state.allUsers, user] })),
+    }),
+    {
+      name: 'chapterx-auth',
+      partialize: s => ({
+        currentUser: s.currentUser,
+        token: s.token,
+        showMatureContent: s.showMatureContent,
+      }),
+    }
+  )
+)