vercel.json

{
    "env": {
      "GOOGLE_SPREADSHEET_ID_PRODUCT": "your_google_spreadsheet_id_for_product_here",
      "GOOGLE_SPREADSHEET_ID_ORDER": "your_google_spreadsheet_id_for_order_here",
      "GOOGLE_SPREADSHEET_ID_CATEGORY": "your_google_spreadsheet_id_for_category_here",
      "GOOGLE_SERVICE_ACCOUNT_CLIENT_EMAIL": "your_google_service_account_client_email_here",
      "GOOGLE_SERVICE_ACCOUNT_PRIVATE_KEY": "your_google_service_account_private_key_here"
    },
    "build": {
      "env": {
        "GOOGLE_SPREADSHEET_ID_PRODUCT": "your_google_spreadsheet_id_for_product_here",
        "GOOGLE_SPREADSHEET_ID_ORDER": "your_google_spreadsheet_id_for_order_here",
        "GOOGLE_SPREADSHEET_ID_CATEGORY": "your_google_spreadsheet_id_for_category_here",
        "GOOGLE_SERVICE_ACCOUNT_CLIENT_EMAIL": "your_google_service_account_client_email_here",
        "GOOGLE_SERVICE_ACCOUNT_PRIVATE_KEY": "your_google_service_account_private_key_here"
      }
    }
  }