diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..f499fd1
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,20 @@
+# Python
+__pycache__/
+*.pyc
+*.pyo
+*.db
+
+# Node
+node_modules/
+frontend/dist/
+
+# IDE
+.vscode/
+.idea/
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Env
+.env
diff --git a/backend/__pycache__/auth.cpython-310.pyc b/backend/__pycache__/auth.cpython-310.pyc
deleted file mode 100644
index 472fea6..0000000
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diff --git a/backend/__pycache__/calculations.cpython-310.pyc b/backend/__pycache__/calculations.cpython-310.pyc
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diff --git a/backend/__pycache__/config.cpython-310.pyc b/backend/__pycache__/config.cpython-310.pyc
deleted file mode 100644
index ec6d96a..0000000
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diff --git a/backend/__pycache__/database.cpython-310.pyc b/backend/__pycache__/database.cpython-310.pyc
deleted file mode 100644
index aec53ff..0000000
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diff --git a/backend/__pycache__/main.cpython-310.pyc b/backend/__pycache__/main.cpython-310.pyc
deleted file mode 100644
index 48af3a8..0000000
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diff --git a/backend/__pycache__/models.cpython-310.pyc b/backend/__pycache__/models.cpython-310.pyc
deleted file mode 100644
index f422413..0000000
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diff --git a/backend/__pycache__/schemas.cpython-310.pyc b/backend/__pycache__/schemas.cpython-310.pyc
deleted file mode 100644
index 1f288d7..0000000
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diff --git a/backend/airlabs.db b/backend/airlabs.db
deleted file mode 100644
index 91408df..0000000
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diff --git a/backend/auth.py b/backend/auth.py
index e6a88cb..7820778 100644
--- a/backend/auth.py
+++ b/backend/auth.py
@@ -38,10 +38,11 @@ def get_current_user(token: str = Depends(oauth2_scheme), db: Session = Depends(
     )
     try:
         payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
-        user_id: int = payload.get("sub")
-        if user_id is None:
+        sub = payload.get("sub")
+        if sub is None:
             raise credentials_exception
-    except JWTError:
+        user_id = int(sub)
+    except (JWTError, ValueError, TypeError):
         raise credentials_exception
 
     user = db.query(User).filter(User.id == user_id).first()
diff --git a/backend/routers/__pycache__/__init__.cpython-310.pyc b/backend/routers/__pycache__/__init__.cpython-310.pyc
deleted file mode 100644
index c5cc7b4..0000000
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diff --git a/backend/routers/__pycache__/auth.cpython-310.pyc b/backend/routers/__pycache__/auth.cpython-310.pyc
deleted file mode 100644
index 851f532..0000000
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diff --git a/backend/routers/__pycache__/costs.cpython-310.pyc b/backend/routers/__pycache__/costs.cpython-310.pyc
deleted file mode 100644
index f3ee76a..0000000
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diff --git a/backend/routers/__pycache__/dashboard.cpython-310.pyc b/backend/routers/__pycache__/dashboard.cpython-310.pyc
deleted file mode 100644
index d10805c..0000000
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diff --git a/backend/routers/__pycache__/projects.cpython-310.pyc b/backend/routers/__pycache__/projects.cpython-310.pyc
deleted file mode 100644
index 330608e..0000000
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diff --git a/backend/routers/__pycache__/submissions.cpython-310.pyc b/backend/routers/__pycache__/submissions.cpython-310.pyc
deleted file mode 100644
index 530a0d0..0000000
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diff --git a/backend/routers/__pycache__/users.cpython-310.pyc b/backend/routers/__pycache__/users.cpython-310.pyc
deleted file mode 100644
index 7234d28..0000000
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diff --git a/backend/routers/auth.py b/backend/routers/auth.py
index 8ee2375..887fbee 100644
--- a/backend/routers/auth.py
+++ b/backend/routers/auth.py
@@ -16,7 +16,7 @@ def login(req: LoginRequest, db: Session = Depends(get_db)):
         raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="用户名或密码错误")
     if not user.is_active:
         raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail="账号已停用")
-    token = create_access_token(data={"sub": user.id})
+    token = create_access_token(data={"sub": str(user.id)})
     return {"access_token": token, "token_type": "bearer"}
 
 
diff --git a/frontend/.vscode/extensions.json b/frontend/.vscode/extensions.json
deleted file mode 100644
index a7cea0b..0000000
--- a/frontend/.vscode/extensions.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "recommendations": ["Vue.volar"]
-}
diff --git a/frontend/src/api/index.js b/frontend/src/api/index.js
index 3ab61a7..7d7a6fd 100644
--- a/frontend/src/api/index.js
+++ b/frontend/src/api/index.js
@@ -22,9 +22,12 @@ api.interceptors.response.use(
   err => {
     const msg = err.response?.data?.detail || '请求失败'
     if (err.response?.status === 401) {
+      const isOnLogin = window.location.pathname === '/login'
       localStorage.removeItem('token')
-      router.push('/login')
-      ElMessage.error('登录已过期，请重新登录')
+      if (!isOnLogin) {
+        router.push('/login')
+        ElMessage.error('登录已过期，请重新登录')
+      }
     } else {
       ElMessage.error(msg)
     }
diff --git a/frontend/src/router/index.js b/frontend/src/router/index.js
index bdc8b60..ca6b2ae 100644
--- a/frontend/src/router/index.js
+++ b/frontend/src/router/index.js
@@ -27,7 +27,12 @@ const router = createRouter({
 router.beforeEach(async (to, from, next) => {
   const token = localStorage.getItem('token')
   if (to.meta.public) {
-    next()
+    // 已登录时访问登录页，直接跳首页
+    if (to.path === '/login' && token) {
+      next('/')
+    } else {
+      next()
+    }
   } else if (!token) {
     next('/login')
   } else {
diff --git a/frontend/src/stores/auth.js b/frontend/src/stores/auth.js
index e97d866..ad10cf6 100644
--- a/frontend/src/stores/auth.js
+++ b/frontend/src/stores/auth.js
@@ -10,10 +10,16 @@ export const useAuthStore = defineStore('auth', () => {
     const res = await authApi.login({ username, password })
     token.value = res.access_token
     localStorage.setItem('token', res.access_token)
-    await fetchUser()
+    // 登录后立即获取用户信息，失败不影响登录流程
+    try {
+      user.value = await authApi.me()
+    } catch (e) {
+      console.error('fetchUser after login failed:', e)
+    }
   }
 
   async function fetchUser() {
+    if (!token.value) return
     try {
       user.value = await authApi.me()
     } catch {