Highlight Link

<a class="kodza-highlight" href="#">Copy-paste and chill</a>

<a class="kodza-highlight kodza-highlight--invert" href="#">Skip the setup</a>

/* Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license */
/* Kodza — Highlight Link
   A highlighter stroke sweeps in behind the text from the left and leaves through the
   right. Drawn as a background, it follows the text across several lines.
   The --invert variant passes a solid block instead: the text turns white exactly under
   its edge (single line, made for light or dark monochrome backgrounds).
   Everything is tuned with the --kz-highlight-* variables. */
.kodza-highlight {
  --kz-highlight-text: currentColor;
  --kz-highlight-mark: rgba(10, 10, 10, 0.12);
  --kz-highlight-height: 100%;
  --kz-highlight-duration: 0.55s;
  --kz-highlight-ease: cubic-bezier(0.76, 0, 0.24, 1);

  color: var(--kz-highlight-text);
  text-decoration: none;
  background-image: linear-gradient(var(--kz-highlight-mark), var(--kz-highlight-mark));
  background-repeat: no-repeat;
  background-position: 100% 100%;
  background-size: 0% var(--kz-highlight-height);
  padding: 0.02em 0.14em;
  margin: 0 -0.14em;
  border-radius: 0.12em;
  /* Only the width moves: the anchor flips instantly, while it changes nothing on screen */
  transition: background-size var(--kz-highlight-duration) var(--kz-highlight-ease);
}

.kodza-highlight:hover,
.kodza-highlight:focus-visible {
  background-position: 0 100%;
  background-size: 100% var(--kz-highlight-height);
}

/* Invert: a white block in "difference" mode shows as ink over a light page,
   and flips the text it covers to white, pixel by pixel */
.kodza-highlight--invert {
  position: relative;
  display: inline-block;
  background-image: none;
  margin: 0;
}

.kodza-highlight--invert::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: #ffffff;
  mix-blend-mode: difference;
  transform: scaleX(0);
  transform-origin: 100% 50%;
  transition: transform var(--kz-highlight-duration) var(--kz-highlight-ease);
  pointer-events: none;
}

.kodza-highlight--invert:hover::after,
.kodza-highlight--invert:focus-visible::after {
  transform: scaleX(1);
  transform-origin: 0 50%;
}

.kodza-highlight:focus-visible {
  outline: 2px solid currentColor;
  outline-offset: 4px;
}

@media (prefers-reduced-motion: reduce) {
  .kodza-highlight,
  .kodza-highlight--invert::after {
    transition-duration: 0.01ms;
  }
}

/* Theming example — a warmer marker:
.kodza-highlight {
  --kz-highlight-mark: #f3e3a3;
  --kz-highlight-height: 45%;
}
*/

/* kodza-guard a42e4f4deea1 — 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-highlight):not(#_) {
  outline: revert;
  position: revert;
  outline-offset: revert;
}

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

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

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

.kodza-highlight:not(#_) {
  border: revert;
  list-style: revert;
  box-sizing: revert;
  background-color: revert;
  box-shadow: revert;
  appearance: 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;
}

/* 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-highlight:not(#_) {
  color: var(--kz-highlight-text);
  text-decoration: none;
  background-image: linear-gradient(var(--kz-highlight-mark), var(--kz-highlight-mark));
  padding: 0.02em 0.14em;
  border-radius: 0.12em;
  transition: background-size var(--kz-highlight-duration) var(--kz-highlight-ease);
}

.kodza-highlight--invert:not(#_) {
  position: relative;
  display: inline-block;
  background-image: none;
}

.kodza-highlight:focus-visible:not(#_) {
  outline: 2px solid currentColor;
  outline-offset: 4px;
}

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

'use client';
// Kodza — Highlight Link, for React. From https://kodza.dev/components/hover-link-text-background-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: hover-link-text-background-reveal.css, the component's CSS from Kodza, as they are.
// Yours to edit: the markup is plain JSX below.
import { useRef, type ComponentPropsWithoutRef, type ComponentRef, type CSSProperties } from 'react';
import './hover-link-text-background-reveal.css';

type Variant = "invert";

export type HighlightLinkProps = Omit<ComponentPropsWithoutRef<'a'>, "children" | "variant" | "vars"> & {
  /** Modifier class(es): .kodza-highlight--invert */
  variant?: Variant | Variant[];
  /** Settings, as CSS variables on the root */
  vars?: {
    /** default: currentColor */
    "--kz-highlight-text"?: string | number;
    /** default: rgba(10, 10, 10, 0.12) */
    "--kz-highlight-mark"?: string | number;
    /** default: 100% */
    "--kz-highlight-height"?: string | number;
    /** default: 0.55s */
    "--kz-highlight-duration"?: string | number;
    /** default: cubic-bezier(0.76, 0, 0.24, 1) */
    "--kz-highlight-ease"?: string | number;
  };
  /** The text */
  children?: string;
  className?: string;
};

export function HighlightLink({ variant, vars, children = "Copy-paste and chill", className, style, ...rest }: HighlightLinkProps) {
  const ref = useRef<ComponentRef<'a'>>(null);
  const classes = ["kodza-highlight", ...([] as string[]).concat(variant ?? []).map((v) => `kodza-highlight--${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, children, style, rest]);

  return (
    <a href="#" key={key} {...rest} className={classes} style={{ ...vars, ...style } as CSSProperties} ref={ref}>{children}</a>
  );
}