JQuery Library using ES6 Class

JQuery.js

class MiniQuery {
    constructor(selector) {
        this.elements = document.querySelectorAll(selector);
    }

    css(property, value) {
        this.elements.forEach(el => el.style[property] = value);
        return this; // Enable chaining
    }

    text(content) {
        if (content === undefined) {
            return this.elements[0]?.textContent;
        }
        this.elements.forEach(el => el.textContent = content);
        return this;
    }

    html(content) {
        if (content === undefined) {
            return this.elements[0]?.innerHTML;
        }
        this.elements.forEach(el => el.innerHTML = content);
        return this;
    }

    addClass(className) {
        this.elements.forEach(el => el.classList.add(className));
        return this;
    }

    removeClass(className) {
        this.elements.forEach(el => el.classList.remove(className));
        return this;
    }

    on(event, callback) {
        this.elements.forEach(el => el.addEventListener(event, callback));
        return this;
    }

    off(event, callback) {
        this.elements.forEach(el => el.removeEventListener(event, callback));
        return this;
    }

    static ajax({ url, method = "GET", data = null, success, error }) {
        fetch(url, {
            method,
            headers: { "Content-Type": "application/json" },
            body: data ? JSON.stringify(data) : null
        })
        .then(res => res.json())
        .then(data => success && success(data))
        .catch(err => error && error(err));
    }
}

// Shorter alias for convenience
const $ = (selector) => new MiniQuery(selector);

// Example Usage
$(document).ready = (callback) => document.addEventListener("DOMContentLoaded", callback);

// Example: Manipulating elements
$(document).ready(() => {
    $(".title").css("color", "blue").text("Hello, MiniQuery!");
    
    $(".btn").on("click", function () {
        $(".title").addClass("highlight");
    });
});

// Example: AJAX Request
MiniQuery.ajax({
    url: "https://jsonplaceholder.typicode.com/posts/1",
    success: (data) => console.log("Data received:", data),
    error: (err) => console.error("Error:", err)
});