api.js

```javascript
import axios from 'axios';

const API_BASE_URL = process.env.VUE_APP_API_URL || 'http://localhost:3000/api';

const api = axios.create({
    baseURL: API_BASE_URL,
    timeout: 10000,
    headers: {
        'Content-Type': 'application/json',
        'Accept': 'application/json'
    }
});

// Add request interceptor for auth
api.interceptors.request.use((config) => {
    const token = localStorage.getItem('authToken');
    if (token) {
        config.headers.Authorization = `Bearer ${token}`;
    }
    return config;
}, (error) => {
    return Promise.reject(error);
});

// Add response interceptor for error handling
api.interceptors.response.use((response) => {
    return response.data;
}, (error) => {
    if (error.response) {
        switch (error.response.status) {
            case 401:
                // Handle unauthorized
                break;
            case 404:
                // Handle not found
                break;
            case 500:
                // Handle server error
                break;
            default:
                // Handle other errors
        }
    }
    return Promise.reject(error);
});

export default {
    // Recipes API
    getRecipes() {
        return api.get('/recipes');
    },
    getRecipe(id) {
        return api.get(`/recipes/${id}`);
    },
    createRecipe(recipe) {
        return api.post('/recipes', recipe);
    },
    updateRecipe(id, recipe) {
        return api.put(`/recipes/${id}`, recipe);
    },
    deleteRecipe(id) {
        return api.delete(`/recipes/${id}`);
    },

    // Calendar API
    getCalendarEvents() {
        return api.get('/calendar');
    },
    createCalendarEvent(event) {
        return api.post('/calendar', event);
    },
    updateCalendarEvent(id, event) {
        return api.put(`/calendar/${id}`, event);
    },
    deleteCalendarEvent(id) {
        return api.delete(`/calendar/${id}`);
    },

    // Grocery API
    getGroceryLists() {
        return api.get('/grocery');
    },
    createGroceryList(list) {
        return api.post('/grocery', list);
    },
    updateGroceryList(id, list) {
        return api.put(`/grocery/${id}`, list);
    },
    deleteGroceryList(id) {
        return api.delete(`/grocery/${id}`);
    }
};
```