scrollTo.js

/**
 * Проскроллить к элементу (верху или низу элемента)
 * 
 * @author https://t.me/artemsites 
 */
export default function scrollTo(params) {
  let { selector, element, position } = params

  let el = null
  if (element) {
    el = element
  } else if (selector) {
    el = document.querySelector(selector)
  }

  if (el) {
    if (position === "bottom") {
    
      const viewportHeight = window.innerHeight || document.documentElement.clientHeight
      const elRect = el.getBoundingClientRect()
      const scrollPosition = elRect.top + window.scrollY - viewportHeight + elRect.height
  
      window.scrollTo({
        top: scrollPosition,
        behavior: 'smooth'
      })
  
    } else {
      // "top"
      el?.scrollIntoView({behavior: "smooth"})
    }
  }

}