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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

<h1>Componentes encapsulados (shadow root)</h1>

<p>Este es el popup info: <popup-info img="https://s3-us-west-2.amazonaws.com/s.cdpn.io/222579/cat.svg#redcat" text="De la gata i el belitre jo us diré lo que ha passat: s'ha perdut alguna cosa, no sé qui l'haurà trobat." ></popup-info> que acabamos de crear</p>
              popup-info{display: inline; position:relative; top:.2rem;}
              class PopUpInfo extends HTMLElement {
  constructor() {
    // cuando se trata de una clase que extiende otra clase tenemos que utilizar la palabra clave super para invocar la clase padre

    // creando shadow root
    var shadow = this.attachShadow({ mode: "open" });
    // si mode es "open" quiere decir que que es posible acceder y  manipular el shadow DOM con JavaScript

    // Creando la estructura del shadow DOM
    var wrapper = document.createElement("span");
    wrapper.setAttribute("class", "wrapper");

    var icon = document.createElement("span");
    icon.setAttribute("class", "icon");
    icon.setAttribute("tabindex", 0);

    var info = document.createElement("span");
    info.setAttribute("class", "info");

    // Toma el valor del atributo text del popup-info y lo utiliza como text-content de info
    var text = this.getAttribute("text");
    info.textContent = text;

    // Añade la imágen para el ícono
    var imgUrl;
    if (this.hasAttribute("img")) {
      imgUrl = this.getAttribute("img");
    } else {
      imgUrl =
    var img = document.createElement("img");
    img.src = imgUrl;

    //Los estilos para el shadow DOM
    var style = document.createElement("style");

    style.textContent = `
.wrapper {
  position: relative;

.info {
  font-size: 0.8rem;
  width: 200px;
  display: inline-block;
  border: 1px solid black;
  padding: 10px;
  background: white;
  border-radius: 10px;
  opacity: 0;
  transition: 0.6s all;
  position: absolute;
  bottom: 20px;
  left: 10px;
  z-index: 3;

img {
  width: 1.2rem;

.icon:hover + .info, .icon:focus + .info {
  opacity: 1;


// Definir el nuevo elemento
customElements.define("popup-info", PopUpInfo);

// // Una vez definida la nueva clase de elementos, podemos utilizar el nuevo tipo de elementos en el HTML

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