ntListener('DOMContentLoaded', () => {
            const containerEle = document.getElementById('container');
            const textarea = document.getElementById('textarea');

            const mirroredEle = document.createElement('div');
            mirroredEle.textContent = textarea.value;
            mirroredEle.classList.add('container__mirror');
            containerEle.prepend(mirroredEle);

            const textareaStyles = window.getComputedStyle(textarea);
            [
                'border',
