ClojureScript scroll element into view

scroll.cljs

;; Based on https://github.com/GabrielDelepine/smooth-scroll/blob/main/smooth-scroll.js
(ns example.scroll)

(def speed 500)
(def moving-frequency 15)

(defn cur-doc-top []
  (+ (.. js/document -body -scrollTop) (.. js/document -documentElement -scrollTop)))

(defn element-top [elem top]
  (if (.-offsetParent elem)
    (let [client-top (or (.-clientTop elem) 0)
          offset-top (.-offsetTop elem)]
      (+ top client-top offset-top (element-top (.-offsetParent elem) top)))
    top))

(defn scroll-to-id
  [elem-id]
  (let [elem (.getElementById js/document elem-id)
        hop-count (/ speed moving-frequency)
        doc-top (cur-doc-top)
        gap (/ (- (element-top elem 0) doc-top) hop-count)]
    (doseq [i (range 1 (inc hop-count))]
      (let [hop-top-pos (* gap i)
            move-to (+ hop-top-pos doc-top)
            timeout (* moving-frequency i)]
        (.setTimeout js/window (fn []
                                 (.scrollTo js/window 0 move-to))
                     timeout)))))

ClojureScript implementation of Gabriel Delépine's Smooth-Scroll project.