Breadcrumbs

<nav class="kodza-breadcrumbs" aria-label="Breadcrumb">
  <ol class="kodza-breadcrumbs__list">
    <li class="kodza-breadcrumbs__item"><a class="kodza-breadcrumbs__link" href="#">Home</a></li>
    <li class="kodza-breadcrumbs__item"><a class="kodza-breadcrumbs__link" href="#">Docs</a></li>
    <li class="kodza-breadcrumbs__item"><a class="kodza-breadcrumbs__link" href="#">Components</a></li>
    <li class="kodza-breadcrumbs__item"><span class="kodza-breadcrumbs__current" aria-current="page">Breadcrumbs</span></li>
  </ol>
</nav>

<nav class="kodza-breadcrumbs kodza-breadcrumbs--collapse" aria-label="Breadcrumb">
  <ol class="kodza-breadcrumbs__list">
    <li class="kodza-breadcrumbs__item"><a class="kodza-breadcrumbs__link" href="#">Home</a></li>
    <li class="kodza-breadcrumbs__item"><a class="kodza-breadcrumbs__link" href="#">Side projects</a></li>
    <li class="kodza-breadcrumbs__item"><a class="kodza-breadcrumbs__link" href="#">Unfinished</a></li>
    <li class="kodza-breadcrumbs__item"><a class="kodza-breadcrumbs__link" href="#">2019</a></li>
    <li class="kodza-breadcrumbs__item"><span class="kodza-breadcrumbs__current" aria-current="page">todo-app-final-v3</span></li>
  </ol>
</nav>

/* Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license */
/* Kodza — Breadcrumbs
   Where the visitor is, one link per level. When the trail would not fit on one line (or
   always, with the --collapse modifier), its middle folds behind a "…" button that unfolds
   it, crumb after crumb. Without JS, the whole trail shows and wraps.
   Everything is tuned with the --kz-crumbs-* variables. */
.kodza-breadcrumbs {
  --kz-crumbs-fg: #0a0a0a;
  --kz-crumbs-muted: rgba(10, 10, 10, 0.58);
  --kz-crumbs-separator: rgba(10, 10, 10, 0.28);
  --kz-crumbs-soft: rgba(10, 10, 10, 0.06);
  --kz-crumbs-soft-fg: #ffffff;
  --kz-crumbs-size: 15px;
  --kz-crumbs-gap: 10px;
  --kz-crumbs-ease: cubic-bezier(0.22, 1, 0.36, 1);

  font-size: var(--kz-crumbs-size);
  line-height: 1.4;
  color: var(--kz-crumbs-fg);
}

.kodza-breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px var(--kz-crumbs-gap);
  margin: 0;
  padding: 0;
  list-style: none;
}

.kodza-breadcrumbs__item {
  display: inline-flex;
  align-items: center;
  gap: var(--kz-crumbs-gap);
  min-width: 0;
}

/* The slash says which way the path goes */
.kodza-breadcrumbs__item + .kodza-breadcrumbs__item::before {
  content: "/";
  color: var(--kz-crumbs-separator);
}

.kodza-breadcrumbs__link {
  border-radius: 4px;
  background: linear-gradient(currentColor, currentColor) 0 100% / 0 1px no-repeat;
  color: var(--kz-crumbs-muted);
  text-decoration: none;
  transition: color 0.25s ease, background-size 0.4s var(--kz-crumbs-ease);
}

.kodza-breadcrumbs__link:hover {
  background-size: 100% 1px;
  color: var(--kz-crumbs-fg);
}

.kodza-breadcrumbs__link:focus-visible,
.kodza-breadcrumbs__more button:focus-visible {
  outline: 2px solid var(--kz-crumbs-fg);
  outline-offset: 3px;
}

.kodza-breadcrumbs__current {
  overflow: hidden;
  font-weight: 500;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* The fold: only shown while the middle is folded */
.kodza-breadcrumbs__more {
  display: none;
}

.kodza-breadcrumbs__more button {
  display: grid;
  place-items: center;
  width: 32px;
  height: 24px;
  padding: 0 0 4px;
  border: 0;
  border-radius: 999px;
  background: var(--kz-crumbs-soft);
  color: var(--kz-crumbs-muted);
  font: inherit;
  line-height: 1;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: background-color 0.25s ease, color 0.25s ease;
}

.kodza-breadcrumbs__more button:hover {
  background: var(--kz-crumbs-fg);
  color: var(--kz-crumbs-soft-fg);
}

.kodza-breadcrumbs.is-collapsed .kodza-breadcrumbs__more {
  display: inline-flex;
}

.kodza-breadcrumbs.is-collapsed .kodza-breadcrumbs__folded {
  display: none;
}

/* Unfolding: the hidden crumbs slide in one after the other */
.kodza-breadcrumbs.is-unfolding .kodza-breadcrumbs__folded {
  animation: kodza-crumbs-in 0.6s var(--kz-crumbs-ease) both;
  animation-delay: calc(80ms + var(--i, 0) * 70ms);
}

@keyframes kodza-crumbs-in {
  from {
    opacity: 0;
    transform: translateX(-12px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .kodza-breadcrumbs.is-unfolding .kodza-breadcrumbs__folded {
    animation: none;
  }

  .kodza-breadcrumbs__link,
  .kodza-breadcrumbs__more button {
    transition-duration: 0.01ms !important;
  }
}

/* Theming example — on a dark background:
.dark-section .kodza-breadcrumbs {
  --kz-crumbs-fg: #f2f2f0;
  --kz-crumbs-muted: rgba(242, 242, 240, 0.6);
  --kz-crumbs-separator: rgba(242, 242, 240, 0.3);
  --kz-crumbs-soft: rgba(255, 255, 255, 0.1);
  --kz-crumbs-soft-fg: #0a0a0a;
}
*/

/* kodza-guard 70c65248e6f4 — 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, where the component sets it only in some states: at the lowest weight, so its own rules below put it back */

:where(.kodza-breadcrumbs__link):not(#_),
:where(.kodza-breadcrumbs__item button:where(:not([class*="kodza-"]))):not(#_) {
  outline: revert;
  outline-offset: revert;
}

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

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

.kodza-breadcrumbs__list:not(#_) {
  border: revert;
  border-radius: revert;
  outline: revert;
  text-decoration: revert;
  transition: 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;
  color: revert;
  font-family: revert;
  font-size: 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-breadcrumbs__item:not(#_) {
  border: revert;
  margin: 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;
  color: revert;
  font-family: revert;
  font-size: 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-breadcrumbs__link:not(#_) {
  border: revert;
  margin: revert;
  padding: revert;
  list-style: revert;
  box-sizing: revert;
  float: revert;
  position: revert;
  box-shadow: revert;
  appearance: revert;
  max-width: revert;
  max-height: revert;
  font-family: revert;
  font-size: 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-breadcrumbs__current:not(#_) {
  box-sizing: revert;
}

.kodza-breadcrumbs__item button:where(:not([class*="kodza-"])):not(#_) {
  margin: revert;
  text-decoration: revert;
  list-style: revert;
  box-sizing: revert;
  float: revert;
  position: revert;
  box-shadow: revert;
  appearance: revert;
  max-width: revert;
  max-height: revert;
  text-transform: revert;
  text-underline-offset: revert;
  text-align: revert;
  text-indent: revert;
  text-shadow: revert;
  vertical-align: revert;
  white-space: revert;
  min-height: revert;
}

.kodza-breadcrumbs:not(#_):where(:not([hidden])),
.kodza-breadcrumbs__link:not(#_):where(:not([hidden])) {
  display: revert;
}

.kodza-breadcrumbs:not(#_):where([hidden]),
.kodza-breadcrumbs__link:not(#_):where([hidden]) {
  display: none;
}

.kodza-breadcrumbs__item:not(#_)::before {
  box-sizing: revert;
}

/* 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-breadcrumbs:not(#_) {
  font-size: var(--kz-crumbs-size);
  line-height: 1.4;
  color: var(--kz-crumbs-fg);
}

.kodza-breadcrumbs__list:not(#_) {
  display: flex;
  margin: 0;
  padding: 0;
  list-style: none;
}

.kodza-breadcrumbs__item:not(#_) {
  display: inline-flex;
}

.kodza-breadcrumbs__link:not(#_) {
  border-radius: 4px;
  background: linear-gradient(currentColor, currentColor) 0 100% / 0 1px no-repeat;
  color: var(--kz-crumbs-muted);
  text-decoration: none;
  transition: color 0.25s ease, background-size 0.4s var(--kz-crumbs-ease);
}

.kodza-breadcrumbs__link:hover:not(#_) {
  background-size: 100% 1px;
  color: var(--kz-crumbs-fg);
}

.kodza-breadcrumbs__link:focus-visible:not(#_) {
  outline: 2px solid var(--kz-crumbs-fg);
  outline-offset: 3px;
}

.kodza-breadcrumbs__more button:focus-visible:not(#_) {
  outline: 2px solid var(--kz-crumbs-fg);
  outline-offset: 3px;
}

.kodza-breadcrumbs__more:not(#_) {
  display: none;
}

.kodza-breadcrumbs__more button:not(#_) {
  display: grid;
  place-items: center;
  width: 32px;
  height: 24px;
  padding: 0 0 4px;
  border: 0;
  border-radius: 999px;
  background: var(--kz-crumbs-soft);
  color: var(--kz-crumbs-muted);
  font: inherit;
  line-height: 1;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: background-color 0.25s ease, color 0.25s ease;
}

.kodza-breadcrumbs__more button:hover:not(#_) {
  background: var(--kz-crumbs-fg);
  color: var(--kz-crumbs-soft-fg);
}

.kodza-breadcrumbs.is-collapsed .kodza-breadcrumbs__more:not(#_) {
  display: inline-flex;
}

.kodza-breadcrumbs.is-collapsed .kodza-breadcrumbs__folded:not(#_) {
  display: none;
}

@media (prefers-reduced-motion: reduce) {
  .kodza-breadcrumbs__link:not(#_) {
    transition-duration: 0.01ms !important;
  }
}

@media (prefers-reduced-motion: reduce) {
  .kodza-breadcrumbs__more button:not(#_) {
    transition-duration: 0.01ms !important;
  }
}

// Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license
// Kodza — Breadcrumbs
// Folds the middle of the trail behind a "…" button when it would wrap onto a second line
// (or always, with --collapse), and unfolds it on click: the hidden crumbs slide in while the
// others glide to their new place. The first crumb and the last two stay. root.kodzaFold()
// folds it back (after a client-side navigation, or to replay): the crumbs leave in reverse
// order, then the trail closes up around the "…".
(() => {
  const SELECTOR = '.kodza-breadcrumbs';
  const reduceMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;

  // One instance. Everything it starts is tied to `signal`, so kodza:destroy stops it all
  function mount(root, signal) {
    const list = root.querySelector('.kodza-breadcrumbs__list');
    const items = list ? [...list.children] : [];
    root.classList.add('is-ready');
    if (items.length < 4) return;

    const folded = items.slice(1, -2);
    folded.forEach((item, i) => {
      item.classList.add('kodza-breadcrumbs__folded');
      item.style.setProperty('--i', i);
    });

    const more = document.createElement('li');
    const button = document.createElement('button');
    more.className = 'kodza-breadcrumbs__item kodza-breadcrumbs__more';
    button.type = 'button';
    button.textContent = '…';
    button.setAttribute('aria-label', `Show ${folded.length} hidden levels`);
    more.append(button);
    items[0].after(more);

    let unfolded = false;
    const fold = (on) => root.classList.toggle('is-collapsed', on);
    // One line high, or wrapping?
    const fits = () => {
      fold(false);
      return list.offsetHeight <= items[0].offsetHeight * 1.5;
    };
    const update = () => {
      if (!unfolded) fold(root.classList.contains('kodza-breadcrumbs--collapse') || !fits());
    };

    // The crumbs that stay on screen glide to their new place (measured before and after)
    const stay = items.filter((item) => !folded.includes(item));
    const measure = () => new Map(stay.map((item) => [item, item.getBoundingClientRect()]));
    const glide = (before) => {
      if (reduceMotion) return;
      // Screen pixels back to the trail's own (a parent may be scaled with a transform)
      const k = root.getBoundingClientRect().width / root.offsetWidth || 1;
      stay.forEach((item) => {
        const from = before.get(item);
        const to = item.getBoundingClientRect();
        const dx = (from.left - to.left) / k;
        const dy = (from.top - to.top) / k;
        if (dx || dy) item.animate([{ transform: `translate(${dx}px, ${dy}px)` }, { transform: 'none' }], { duration: 550, easing: 'cubic-bezier(0.22, 1, 0.36, 1)' });
      });
    };

    button.addEventListener('click', () => {
      // From the keyboard, the focus moves on to the first unfolded crumb
      const fromKeyboard = button.matches(':focus-visible');
      const before = measure();
      unfolded = true;
      root.classList.add('is-unfolding');
      fold(false);
      glide(before);
      if (fromKeyboard) folded[0].querySelector('a, [aria-current]')?.focus({ preventScroll: true });
    }, { signal });

    // Folding back: the hidden crumbs leave in reverse order, then the trail closes up and the
    // "…" comes back where they were
    let leaving = [];
    root.kodzaFold = () => {
      if (!unfolded || leaving.length) return;
      if (!root.classList.contains('kodza-breadcrumbs--collapse') && fits()) return; // it fits now: nothing to fold
      const close = () => {
        leaving.forEach((animation) => animation.cancel());
        leaving = [];
        if (signal.aborted) return;
        if (folded.some((item) => item.contains(document.activeElement))) button.focus({ preventScroll: true });
        const before = measure();
        unfolded = false;
        root.classList.remove('is-unfolding');
        update();
        glide(before);
        if (!reduceMotion) more.animate([{ opacity: 0, transform: 'translateX(-8px)' }, { opacity: 1, transform: 'none' }], { duration: 420, easing: 'cubic-bezier(0.22, 1, 0.36, 1)' });
      };
      if (reduceMotion) return close();
      leaving = folded.map((item, i) => item.animate(
        [{ opacity: 1, transform: 'none' }, { opacity: 0, transform: 'translateX(-12px)' }],
        { duration: 320, delay: (folded.length - 1 - i) * 60, easing: 'cubic-bezier(0.65, 0, 0.35, 1)', fill: 'forwards' }
      ));
      Promise.all(leaving.map((animation) => animation.finished)).then(close, () => {});
    };
    signal.addEventListener('abort', () => {
      leaving.forEach((animation) => animation.cancel());
      delete root.kodzaFold;
    });

    const observer = new ResizeObserver(update);
    observer.observe(root);
    signal.addEventListener('abort', () => observer.disconnect());
    document.fonts?.ready.then(() => !signal.aborted && update());
    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 — Breadcrumbs, for React. From https://kodza.dev/components/breadcrumbs/
// 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: breadcrumbs.css and breadcrumbs.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 './breadcrumbs.css';

type Variant = "collapse";

export type BreadcrumbsProps = Omit<ComponentPropsWithoutRef<'nav'>, "children" | "variant" | "vars"> & {
  /** Modifier class(es): .kodza-breadcrumbs--collapse */
  variant?: Variant | Variant[];
  /** Settings, as CSS variables on the root */
  vars?: {
    /** default: #0a0a0a */
    "--kz-crumbs-fg"?: string | number;
    /** default: rgba(10, 10, 10, 0.58) */
    "--kz-crumbs-muted"?: string | number;
    /** default: rgba(10, 10, 10, 0.28) */
    "--kz-crumbs-separator"?: string | number;
    /** default: rgba(10, 10, 10, 0.06) */
    "--kz-crumbs-soft"?: string | number;
    /** default: #ffffff */
    "--kz-crumbs-soft-fg"?: string | number;
    /** default: 15px */
    "--kz-crumbs-size"?: string | number;
    /** default: 10px */
    "--kz-crumbs-gap"?: string | number;
    /** default: cubic-bezier(0.22, 1, 0.36, 1) */
    "--kz-crumbs-ease"?: string | number;
  };
  className?: string;
};

export function Breadcrumbs({ variant, vars, className, style, ...rest }: BreadcrumbsProps) {
  const ref = useRef<ComponentRef<'nav'>>(null);
  const classes = ["kodza-breadcrumbs", ...([] as string[]).concat(variant ?? []).map((v) => `kodza-breadcrumbs--${v}`), 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('./breadcrumbs.js').then(() => {
      if (live) document.dispatchEvent(new CustomEvent('kodza:init', { detail: { root } }));
    });
    return () => {
      live = false;
      document.dispatchEvent(new CustomEvent('kodza:destroy', { detail: { root } }));
    };
  }, [key]);

  return (
    <nav aria-label="Breadcrumb" key={key} {...rest} className={classes} style={{ ...vars, ...style } as CSSProperties} ref={ref}>
      <ol className="kodza-breadcrumbs__list">
        <li className="kodza-breadcrumbs__item">
          <a className="kodza-breadcrumbs__link" href="#">Home</a>
        </li>
        <li className="kodza-breadcrumbs__item">
          <a className="kodza-breadcrumbs__link" href="#">Docs</a>
        </li>
        <li className="kodza-breadcrumbs__item">
          <a className="kodza-breadcrumbs__link" href="#">Components</a>
        </li>
        <li className="kodza-breadcrumbs__item">
          <span className="kodza-breadcrumbs__current" aria-current="page">Breadcrumbs</span>
        </li>
      </ol>
    </nav>
  );
}