Sticky Scroll Reveal

<section class="kodza-sticky-reveal" aria-label="Why Kodza">
  <div class="kodza-sticky-reveal__stage">
    <p class="kodza-sticky-reveal__label">Why Kodza</p>
    <div class="kodza-sticky-reveal__texts">
      <p class="kodza-sticky-reveal__text">No framework needed.</p>
      <p class="kodza-sticky-reveal__text">Just vanilla JavaScript.</p>
      <p class="kodza-sticky-reveal__text">Simple. Fast. Clean.</p>
      <p class="kodza-sticky-reveal__text">Welcome to Kodza.</p>
    </div>
    <div class="kodza-sticky-reveal__foot" aria-hidden="true">
      <span class="kodza-sticky-reveal__count"><span class="kodza-sticky-reveal__num">01</span><span class="kodza-sticky-reveal__total">/ 04</span></span>
      <span class="kodza-sticky-reveal__bar"><span></span></span>
    </div>
  </div>
</section>

/* Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license */
/* Kodza — Sticky Scroll Reveal
   A block that pins itself while a few big statements take turns as you scroll: each line of
   the current one leaves upwards through its own mask while the next one rises from below
   (the other way round when scrolling back). One statement per gesture: a big scroll never
   skips one. The counter rolls and the bar follows. Without JS, the statements simply stack.
   Everything is tuned with the --kz-sreveal-* variables. */
.kodza-sticky-reveal {
  --kz-sreveal-fg: #0a0a0a;
  --kz-sreveal-muted: rgba(10, 10, 10, 0.62);
  --kz-sreveal-line: rgba(10, 10, 10, 0.12);
  --kz-sreveal-size: clamp(44px, 7.4vw, 108px);
  --kz-sreveal-segment: 75vh;
  --kz-sreveal-gutter: max(24px, calc((100vw - 1080px) / 2));
  --kz-sreveal-duration: 0.9s;
  --kz-sreveal-ease: cubic-bezier(0.22, 1, 0.36, 1);
  --kz-sreveal-stagger: 70ms;

  position: relative;
  color: var(--kz-sreveal-fg);
}

.kodza-sticky-reveal.is-ready {
  height: calc(100vh + var(--kz-sreveal-segment) * (var(--kz-sreveal-n, 4) - 1));
}

.kodza-sticky-reveal__stage {
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 32px;
  padding: 12vh var(--kz-sreveal-gutter) 10vh;
  box-sizing: border-box;
}

.kodza-sticky-reveal.is-ready .kodza-sticky-reveal__stage {
  position: sticky;
  top: 0;
  height: 100vh;
}

.kodza-sticky-reveal__label {
  margin: 0;
  font-family: ui-monospace, "SF Mono", Menlo, monospace;
  font-size: 12px;
  color: var(--kz-sreveal-muted);
}

/* The statements share one cell */
.kodza-sticky-reveal__texts {
  display: grid;
  align-content: center;
}

.kodza-sticky-reveal__text {
  max-width: 11em;
  margin: 0;
  font-size: var(--kz-sreveal-size);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -0.055em;
  text-wrap: balance;
}

.kodza-sticky-reveal.is-ready .kodza-sticky-reveal__text {
  grid-area: 1 / 1;
}

/* Each line in its own window: above, in, or below */
.kodza-sticky-reveal__line {
  display: block;
  overflow: hidden;
  padding-bottom: 0.12em;
  margin-bottom: -0.12em;
}

.kodza-sticky-reveal__line > span {
  display: block;
  transform: translateY(110%);
  transition: transform var(--kz-sreveal-duration) var(--kz-sreveal-ease);
  transition-delay: calc(var(--kz-line, 0) * var(--kz-sreveal-stagger));
}

.kodza-sticky-reveal__text.is-above .kodza-sticky-reveal__line > span {
  transform: translateY(-110%);
}

.kodza-sticky-reveal__text.is-active .kodza-sticky-reveal__line > span {
  transform: none;
  transition-delay: calc(120ms + var(--kz-line, 0) * var(--kz-sreveal-stagger));
}

/* The foot: the counter rolls, the bar follows the scroll */
.kodza-sticky-reveal__foot {
  display: flex;
  align-items: center;
  gap: 20px;
}

.kodza-sticky-reveal__count {
  display: flex;
  gap: 6px;
  font-family: ui-monospace, "SF Mono", Menlo, monospace;
  font-size: 12px;
  font-variant-numeric: tabular-nums;
}

.kodza-sticky-reveal__num {
  display: inline-grid;
  overflow: hidden;
}

.kodza-sticky-reveal__num > span {
  grid-area: 1 / 1;
}

.kodza-sticky-reveal__total {
  color: var(--kz-sreveal-muted);
}

.kodza-sticky-reveal__bar {
  flex: 1;
  height: 1px;
  background: var(--kz-sreveal-line);
}

.kodza-sticky-reveal__bar span {
  display: block;
  height: 100%;
  background: var(--kz-sreveal-fg);
  transform: scaleX(var(--kz-sreveal-progress, 0));
  transform-origin: left;
  transition: transform 0.5s var(--kz-sreveal-ease);
}

.kodza-sticky-reveal:not(.is-ready) .kodza-sticky-reveal__foot {
  display: none;
}

@media (prefers-reduced-motion: reduce) {
  .kodza-sticky-reveal__line > span,
  .kodza-sticky-reveal__bar span {
    transition-duration: 0.01ms !important;
    transition-delay: 0s !important;
  }
}

/* Theming example — on a dark background:
.dark-section .kodza-sticky-reveal {
  --kz-sreveal-fg: #f2f2f0;
  --kz-sreveal-muted: rgba(242, 242, 240, 0.62);
  --kz-sreveal-line: rgba(255, 255, 255, 0.16);
}
*/

/* kodza-guard 22518db15200 — generated by Kodza, do not edit.
   Theme guard: keeps a site's own CSS (WordPress themes, Bootstrap, CSS resets…) off this
   component. :not(#_) is always true and weighs as much as an id, so these lines win over
   theme rules made of classes and tags. Customise the component through its --kz-* variables. */

/* What the browser gives, on everything the component leaves to it */

.kodza-sticky-reveal:not(#_),
.kodza-sticky-reveal__texts:not(#_),
.kodza-sticky-reveal__line:not(#_),
.kodza-sticky-reveal__foot:not(#_),
.kodza-sticky-reveal__count:not(#_),
.kodza-sticky-reveal__num:not(#_),
.kodza-sticky-reveal__total:not(#_),
.kodza-sticky-reveal__bar:not(#_),
.kodza-sticky-reveal__line span:where(:not([class*="kodza-"])):not(#_),
.kodza-sticky-reveal__num span:where(:not([class*="kodza-"])):not(#_),
.kodza-sticky-reveal__bar span:where(:not([class*="kodza-"])):not(#_) {
  box-sizing: revert;
}

.kodza-sticky-reveal__label:not(#_) {
  border: revert;
  padding: revert;
  border-radius: revert;
  outline: revert;
  text-decoration: revert;
  transition: revert;
  list-style: revert;
  box-sizing: revert;
  float: revert;
  position: revert;
  background-color: revert;
  background-image: revert;
  box-shadow: revert;
  outline-offset: revert;
  appearance: revert;
  max-width: revert;
  max-height: revert;
  font-weight: revert;
  font-style: revert;
  line-height: revert;
  letter-spacing: revert;
  text-transform: revert;
  text-underline-offset: revert;
  text-align: revert;
  text-indent: revert;
  text-shadow: revert;
  vertical-align: revert;
}

.kodza-sticky-reveal__text:not(#_) {
  border: revert;
  padding: revert;
  border-radius: revert;
  outline: revert;
  text-decoration: revert;
  transition: revert;
  list-style: revert;
  box-sizing: revert;
  float: revert;
  position: revert;
  background-color: revert;
  background-image: revert;
  box-shadow: revert;
  outline-offset: revert;
  appearance: revert;
  max-height: revert;
  color: revert;
  font-family: revert;
  font-style: revert;
  text-transform: revert;
  text-underline-offset: revert;
  text-align: revert;
  text-indent: revert;
  text-shadow: revert;
  vertical-align: revert;
}

.kodza-sticky-reveal__label:not(#_):where(:not([hidden])),
.kodza-sticky-reveal__text:not(#_):where(:not([hidden])) {
  display: revert;
}

.kodza-sticky-reveal__label:not(#_):where([hidden]),
.kodza-sticky-reveal__text:not(#_):where([hidden]) {
  display: none;
}

/* The component's own rules, one step stronger: real buttons and fields, what it sets on tags themes style (links, lists, headings, images…), and the root width (a theme may narrow it, never widen it) */

.kodza-sticky-reveal__label:not(#_) {
  margin: 0;
  font-family: ui-monospace, "SF Mono", Menlo, monospace;
  font-size: 12px;
  color: var(--kz-sreveal-muted);
}

.kodza-sticky-reveal__text:not(#_) {
  max-width: 11em;
  margin: 0;
  font-size: var(--kz-sreveal-size);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -0.055em;
}

// Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license
// Kodza — Sticky Scroll Reveal
// Gives the block one scroll segment per statement, pins it, and shows the statement of the
// current segment: the statements before it wait above their masks, the ones after below, so
// lines always leave and arrive in the direction of the scroll. One statement per gesture:
// a big scroll never skips one. Lines are cut at the current width (again on resize).
// Fires "kodza:statement" with { index } on the block.
(() => {
  const SELECTOR = '.kodza-sticky-reveal';
  const reduceMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  const pad = (n) => String(n).padStart(2, '0');

  // One instance. Everything it starts is tied to `signal`, so kodza:destroy stops it all
  function mount(root, signal) {
    const texts = [...root.querySelectorAll('.kodza-sticky-reveal__text')];
    const num = root.querySelector('.kodza-sticky-reveal__num');
    const total = root.querySelector('.kodza-sticky-reveal__total');
    if (!texts.length) return;
    const originals = texts.map((text) => text.textContent.trim());
    root.style.setProperty('--kz-sreveal-n', texts.length);
    if (total) total.textContent = `/ ${pad(texts.length)}`;
    if (num) num.replaceChildren(Object.assign(document.createElement('span'), { textContent: pad(1) }));

    // Cut each statement into lines, each in its own window
    const split = () => {
      texts.forEach((text, t) => {
        text.textContent = '';
        const spans = originals[t].split(/\s+/).map((word) => {
          const span = document.createElement('span');
          span.textContent = `${word} `;
          text.append(span);
          return span;
        });
        const lines = [];
        spans.forEach((span) => {
          const last = lines[lines.length - 1];
          if (last && Math.abs(last.top - span.offsetTop) < 2) last.words.push(span.textContent);
          else lines.push({ top: span.offsetTop, words: [span.textContent] });
        });
        text.textContent = '';
        lines.forEach((line, i) => {
          const outer = document.createElement('span');
          const inner = document.createElement('span');
          outer.className = 'kodza-sticky-reveal__line';
          inner.textContent = line.words.join('').trim();
          inner.style.setProperty('--kz-line', i);
          outer.append(inner);
          text.append(outer, ' ');
        });
      });
    };

    // The counter rolls with the direction of the scroll
    const roll = (value, dir) => {
      if (!num) return;
      const prev = num.lastElementChild;
      const span = Object.assign(document.createElement('span'), { textContent: value });
      num.append(span);
      if (reduceMotion) return prev.remove();
      const timing = { duration: 500, easing: 'cubic-bezier(0.22, 1, 0.36, 1)' };
      prev.animate([{ transform: 'none' }, { transform: `translateY(${dir * -110}%)` }], { ...timing, fill: 'forwards' }).finished.then(() => prev.remove());
      span.animate([{ transform: `translateY(${dir * 110}%)` }, { transform: 'none' }], timing);
    };

    let current = -1;
    const show = (index) => {
      if (index === current) return;
      const dir = index > current ? 1 : -1;
      texts.forEach((text, i) => {
        text.classList.toggle('is-active', i === index);
        text.classList.toggle('is-above', i < index);
        text.setAttribute('aria-hidden', String(i !== index));
      });
      if (current >= 0) roll(pad(index + 1), dir);
      current = index;
      root.dispatchEvent(new CustomEvent('kodza:statement', { detail: { index }, bubbles: true }));
    };

    const update = () => {
      const box = root.getBoundingClientRect();
      const length = Math.max(1, box.height - innerHeight);
      const progress = Math.min(1, Math.max(0, -box.top / length));
      root.style.setProperty('--kz-sreveal-progress', progress.toFixed(4));
      show(Math.min(texts.length - 1, Math.floor(progress * texts.length)));
    };

    // One statement per gesture: while the block is pinned, a wheel flick, a swipe or a key
    // moves exactly one statement on, and the rest of the gesture (trackpad inertia) is absorbed.
    // On the first and last statements, the page simply scrolls on, out of the block.
    // data-step="false" turns this off and lets the scroll drive the statements freely.
    if (root.dataset.step !== 'false') {
      const pinned = () => {
        const box = root.getBoundingClientRect();
        return box.top <= 1 && box.bottom >= innerHeight - 1;
      };
      const goTo = (index) => {
        const top = root.getBoundingClientRect().top + window.scrollY;
        const length = Math.max(1, root.offsetHeight - innerHeight);
        window.scrollTo({ top: Math.round(top + (length * (index + 0.5)) / texts.length), behavior: 'instant' });
        update();
      };
      let lockedUntil = 0;
      let lastWheel = 0;
      let lastDelta = 0;
      const step = (dir) => {
        const target = current + dir;
        if (target < 0 || target >= texts.length) return false;
        lockedUntil = performance.now() + 700;
        goTo(target);
        return true;
      };

      let passing = false;
      window.addEventListener('wheel', (event) => {
        if (event.ctrlKey) return;
        const dir = Math.sign(event.deltaY);
        const now = performance.now();
        // A new push: after a pause, or clearly stronger than the fading inertia. Every wheel
        // event counts, so the momentum that carries the page into the block is not a new push.
        const fresh = now - lastWheel > 180 || Math.abs(event.deltaY) > lastDelta * 1.6 + 4;
        lastWheel = now;
        lastDelta = Math.abs(event.deltaY);
        if (fresh) passing = false;
        if (!dir || !pinned()) return;
        const inside = current + dir >= 0 && current + dir < texts.length;
        // Past the first or last statement, a new push leaves the block, momentum included
        if (!inside && (passing || (fresh && now > lockedUntil))) {
          passing = true;
          return;
        }
        event.preventDefault();
        if (fresh && now > lockedUntil) step(dir);
      }, { passive: false, signal });

      window.addEventListener('keydown', (event) => {
        if (!pinned() || event.target.closest?.('input, textarea, select, [contenteditable]')) return;
        const down = ['ArrowDown', 'PageDown'].includes(event.key) || (event.key === ' ' && !event.shiftKey);
        const up = ['ArrowUp', 'PageUp'].includes(event.key) || (event.key === ' ' && event.shiftKey);
        if ((down || up) && step(down ? 1 : -1)) event.preventDefault();
      }, { signal });

      let touchY = null;
      let touchDir = 0;
      root.addEventListener('touchstart', (event) => {
        touchY = event.touches[0].clientY;
        touchDir = 0;
      }, { passive: true, signal });
      root.addEventListener('touchmove', (event) => {
        if (touchY === null || !pinned()) return;
        const dy = touchY - event.touches[0].clientY;
        if (!touchDir && Math.abs(dy) > 6) touchDir = Math.sign(dy);
        const target = current + touchDir;
        if (touchDir && target >= 0 && target < texts.length) event.preventDefault();
      }, { passive: false, signal });
      root.addEventListener('touchend', (event) => {
        if (touchY !== null && touchDir && pinned() && Math.abs(touchY - event.changedTouches[0].clientY) > 30) step(touchDir);
        touchY = null;
      }, { passive: true, signal });
    }

    let ticking = false;
    window.addEventListener('scroll', () => {
      if (ticking) return;
      ticking = true;
      requestAnimationFrame(() => {
        if (signal.aborted) return;
        ticking = false;
        update();
      });
    }, { passive: true, signal });
    let width = innerWidth;
    window.addEventListener('resize', () => {
      if (innerWidth !== width) {
        width = innerWidth;
        split();
      }
      update();
    }, { signal });

    root.classList.add('is-ready');
    split();
    document.fonts?.ready.then(split);
    update();
  }

  // Kodza lifecycle, the same in every component: `kodza:init` starts the instances inside
  // event.detail.root (the whole page by default), `kodza:destroy` stops them and puts their
  // markup back. For themes and apps that swap content without a page load.
  const instances = new WeakMap();
  const find = (scope = document) => [scope, ...scope.querySelectorAll(SELECTOR)].filter((el) => el.matches?.(SELECTOR));
  const init = (scope) => find(scope).forEach((root) => {
    if (root.classList.contains('is-ready')) return; // already running, maybe from another copy of this script
    const controller = new AbortController();
    instances.set(root, { controller, html: root.innerHTML, attrs: [...root.attributes].map((a) => [a.name, a.value]) });
    mount(root, controller.signal);
    root.classList.add('is-ready');
  });
  const destroy = (scope) => find(scope).forEach((root) => {
    const instance = instances.get(root);
    if (!instance) return;
    instances.delete(root);
    instance.controller.abort();
    [...root.attributes].forEach((a) => root.removeAttribute(a.name));
    instance.attrs.forEach(([name, value]) => root.setAttribute(name, value));
    root.innerHTML = instance.html;
  });
  document.addEventListener('kodza:init', (event) => init(event.detail?.root));
  document.addEventListener('kodza:destroy', (event) => destroy(event.detail?.root));
  init();
  // Loaded in <head>, the script runs before the markup exists: once more when it is parsed
  if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', () => init(), { once: true });
})();

'use client';
// Kodza — Sticky Scroll Reveal, for React. From https://kodza.dev/components/sticky-scroll-reveal/
// Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license
// Next to this file: sticky-scroll-reveal.css and sticky-scroll-reveal.js, the component's CSS and JS from Kodza, as they are.
// Yours to edit: the markup is plain JSX below.
// The script changes this markup once React has rendered it (it adds layers, splits text, moves
// nodes), so React must not patch it afterwards. When a prop changes, the key gives React a fresh
// element: kodza:destroy stops the script on the old one, kodza:init starts it on the new one.
import { useRef, useEffect, type ComponentPropsWithoutRef, type ComponentRef, type CSSProperties } from 'react';
import './sticky-scroll-reveal.css';

export type StickyScrollRevealProps = Omit<ComponentPropsWithoutRef<'section'>, "children" | "vars" | "onStatement"> & {
  /** Settings, as CSS variables on the root */
  vars?: {
    /** default: #0a0a0a */
    "--kz-sreveal-fg"?: string | number;
    /** default: rgba(10, 10, 10, 0.62) */
    "--kz-sreveal-muted"?: string | number;
    /** default: rgba(10, 10, 10, 0.12) */
    "--kz-sreveal-line"?: string | number;
    /** default: clamp(44px, 7.4vw, 108px) */
    "--kz-sreveal-size"?: string | number;
    /** default: 75vh */
    "--kz-sreveal-segment"?: string | number;
    /** default: max(24px, calc((100vw - 1080px) / 2)) */
    "--kz-sreveal-gutter"?: string | number;
    /** default: 0.9s */
    "--kz-sreveal-duration"?: string | number;
    /** default: cubic-bezier(0.22, 1, 0.36, 1) */
    "--kz-sreveal-ease"?: string | number;
    /** default: 70ms */
    "--kz-sreveal-stagger"?: string | number;
  };
  /** "kodza:statement", fired by the script (bubbles from the root) */
  onStatement?: (event: CustomEvent) => void;
  className?: string;
};

export function StickyScrollReveal({ vars, onStatement, className, style, ...rest }: StickyScrollRevealProps) {
  const ref = useRef<ComponentRef<'section'>>(null);
  const classes = ["kodza-sticky-reveal", className].filter(Boolean).join(' ');
  // Everything the markup is made of: when it changes, React gets a fresh element (see the top)
  const key = JSON.stringify([classes, vars, style, rest]);

  // Starts the script on this element once React has rendered it, stops it when it goes
  useEffect(() => {
    const root = ref.current;
    let live = true;
    // @ts-ignore: a plain script, no types to find
    import('./sticky-scroll-reveal.js').then(() => {
      if (live) document.dispatchEvent(new CustomEvent('kodza:init', { detail: { root } }));
    });
    return () => {
      live = false;
      document.dispatchEvent(new CustomEvent('kodza:destroy', { detail: { root } }));
    };
  }, [key]);

  useEffect(() => {
    const root = ref.current;
    if (!root || !onStatement) return;
    const listener = (event: Event) => onStatement(event as CustomEvent);
    root.addEventListener("kodza:statement", listener);
    return () => root.removeEventListener("kodza:statement", listener);
  }, [onStatement, key]);

  return (
    <section aria-label="Why Kodza" key={key} {...rest} className={classes} style={{ ...vars, ...style } as CSSProperties} ref={ref}>
      <div className="kodza-sticky-reveal__stage">
        <p className="kodza-sticky-reveal__label">Why Kodza</p>
        <div className="kodza-sticky-reveal__texts">
          <p className="kodza-sticky-reveal__text">No framework needed.</p>
          <p className="kodza-sticky-reveal__text">Just vanilla JavaScript.</p>
          <p className="kodza-sticky-reveal__text">Simple. Fast. Clean.</p>
          <p className="kodza-sticky-reveal__text">Welcome to Kodza.</p>
        </div>
        <div className="kodza-sticky-reveal__foot" aria-hidden="true">
          <span className="kodza-sticky-reveal__count">
            <span className="kodza-sticky-reveal__num">01</span>
            <span className="kodza-sticky-reveal__total">/ 04</span>
          </span>
          {' '}
          <span className="kodza-sticky-reveal__bar">
            <span />
          </span>
        </div>
      </div>
    </section>
  );
}