怎么写js特效

const images = document.querySelectorAll('.carousel-image');
let currentIndex = 0;

function showNextImage() {
  images[currentIndex].style.display = 'none';
  currentIndex = (currentIndex + 1) % images.length;
  images[currentIndex].style.display = 'block';
}

setInterval(showNextImage, 3000);

const button = document.querySelector('.open-popup-button');
const popup = document.querySelector('.popup');

button.addEventListener('click', () => {
  popup.style.display = 'block';
});

popup.querySelector('.close-button').addEventListener('click', () => {
  popup.style.display = 'none';
});

window.addEventListener('scroll', () => {
  const navbar = document.querySelector('.navbar');
  if (window.scrollY > 100) {
    navbar.classList.add('fixed');
  } else {
    navbar.classList.remove('fixed');
  }
});

const images = document.querySelectorAll('.lazy-image');

function lazyLoad() {
  images.forEach(image => {
    if (image.offsetTop < window.innerHeight + window.scrollY) {
      image.src = image.dataset.src;
      image.classList.remove('lazy-image');
    }
  });
}

window.addEventListener('scroll', lazyLoad);
window.addEventListener('load', lazyLoad);

const textElement = document.querySelector('.typing-text');
const text = "Hello, World!";
let index = 0;

function typeWriter() {
  if (index < text.length) {
    textElement.textContent += text.charAt(index);
    index++;
    setTimeout(typeWriter, 100);
  }
}

typeWriter();