diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000..ff3bde7
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,93 @@
+# Android CI — 7maHelper (4ma 用车计时助手)
+#
+# 触发条件:
+#   - push / pull_request 到 main 或 master
+#   - 手动触发 (Actions 页面的 Run workflow 按钮)
+#
+# 任务:
+#   1. JDK 17 + Android SDK (platforms;android-35, build-tools;35.0.0)
+#   2. Gradle wrapper 校验 + 依赖缓存 (gradle/actions/setup-gradle)
+#   3. 构建 Debug / Release APK
+#   4. 上传 APK 为 Actions artifact
+
+name: Android CI
+
+on:
+  push:
+    branches: [ main, master ]
+  pull_request:
+    branches: [ main, master ]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    name: Build APK
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '17'
+
+      - name: Set up Android SDK
+        run: |
+          # GitHub 托管 runner 已预装 Android SDK (ANDROID_HOME 默认已设置)，
+          # 这里只显式安装本项目所需的平台与构建工具，并接受所有许可。
+          yes | sdkmanager --licenses >/dev/null 2>&1 || true
+          sdkmanager "platforms;android-35" "build-tools;35.0.0"
+
+      - name: Set up Gradle
+        uses: gradle/actions/setup-gradle@v4
+
+      - name: Grant execute permission for gradlew
+        run: chmod +x gradlew
+
+      - name: Build with Gradle
+        # local.properties 已被 .gitignore 忽略，CI 上不存在；
+        # AGP 自动使用 ANDROID_HOME 环境变量定位 SDK。
+        run: ./gradlew assembleDebug assembleRelease --no-daemon
+
+      - name: Upload APK artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: apk
+          path: |
+            app/build/outputs/apk/debug/*.apk
+            app/build/outputs/apk/release/*.apk
+          if-no-files-found: error
+
+      # 可选：对 Release APK 进行正式签名。
+      # 启用方法（在仓库 Settings -> Secrets and variables -> Actions 中配置）:
+      #   KEYSTORE_BASE64  - base64 编码的 keystore 文件内容
+      #   KEYSTORE_PASSWORD / KEY_ALIAS / KEY_PASSWORD
+      # 未配置时此步骤自动跳过。
+      - name: Sign Release APK (optional)
+        if: env.KEYSTORE_BASE64 != ''
+        env:
+          KEYSTORE_BASE64: ${{ secrets.KEYSTORE_BASE64 }}
+          KEYSTORE_PASSWORD: ${{ secrets.KEYSTORE_PASSWORD }}
+          KEY_ALIAS: ${{ secrets.KEY_ALIAS }}
+          KEY_PASSWORD: ${{ secrets.KEY_PASSWORD }}
+        run: |
+          APK="app/build/outputs/apk/release/app-release-unsigned.apk"
+          if [ -f "$APK" ]; then
+            echo "$KEYSTORE_BASE64" | base64 -d > release.keystore
+            "$ANDROID_HOME/build-tools/35.0.0/apksigner" sign \
+              --ks release.keystore \
+              --ks-pass "pass:${KEYSTORE_PASSWORD}" \
+              --key-pass "pass:${KEY_PASSWORD}" \
+              --ks-key-alias "$KEY_ALIAS" \
+              --out app/build/outputs/apk/release/app-release.apk \
+              "$APK"
+            echo "已签名: app/build/outputs/apk/release/app-release.apk"
+          else
+            echo "未找到 release 未签名 APK，跳过签名"
+          fi
diff --git a/.gitignore b/.gitignore
index c27b900..27bcd8b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,6 +7,10 @@ app/build/
 *.apk
 local.properties
 
+# 签名密钥
+release.keystore
+release.keystore.b64
+
 # 自包含的工具链（体积大，若用 git 建议忽略；重装见 SETUP.md）
 android-sdk/
 tools/*