Documentation

Student-friendly HTML, CSS, and JavaScript reference with examples

Sections


                                        querySelector()


                                        querySelectorAll()


                                        .textContent


                                        .value


                                        for...of (DOM)


                                        addEventListener()


                                        'click'


                                        'input'


                                        .style


                                        .classList.add()


                                        .classList.remove()


                                        .classList.toggle()


                                        createElement()


                                        .appendChild()


                                        .remove()


                                        .parentElement


                                        .getAttribute()


                                        data-*

Adds a CSS class to an element.

const button = document.querySelector('button');

button.classList.add('active');
button.classList.add('highlight', 'large'); // Add multiple

The element now has the class and gets its styles from CSS.