Add ARIA attributes and focus management to cookie banner

Improve accessibility across the cookie banner components: add
aria-modal/aria-labelledby/aria-describedby on dialog cards, aria-label
on icon-only buttons and category toggles, aria-expanded on cookie
detail disclosure, aria-hidden on decorative SVGs, and auto-focus into
dialogs when they become visible.

Signed-off-by: Émile Ré <emile@getprobo.com>

packages/cookie-banner/src/components/banner.ts

@@ -27,6 +27,9 @@ export class ProboBanner extends ProboElement {
   private onStateChange = (e: Event): void => {
     const { state } = (e as CustomEvent).detail;
     this.hidden = state !== "banner";
+    if (state === "banner") {
+      this.focusFirst();
+    }
   };
 
   connectedCallback(): void {

packages/cookie-banner/src/components/base.ts

@@ -20,7 +20,16 @@ export interface ConsentDraft {
   [category: string]: boolean;
 }
 
+const FOCUSABLE = 'a[href],button:not([disabled]),input:not([disabled]),select:not([disabled]),textarea:not([disabled]),[tabindex]:not([tabindex="-1"])';
+
 export class ProboElement extends HTMLElement {
+  protected focusFirst(): void {
+    requestAnimationFrame(() => {
+      const el = this.querySelector<HTMLElement>(FOCUSABLE);
+      el?.focus();
+    });
+  }
+
   protected findAncestor<T extends HTMLElement>(tagName: string): T | null {
     let el: HTMLElement | null = this.parentElement;
     while (el) {

packages/cookie-banner/src/components/category-toggle.ts

@@ -49,6 +49,7 @@ export class ProboCategoryToggle extends ProboElement {
     if (!this.category || !this.root) return;
 
     const name = this.category.categoryName;
+    this.checkbox.setAttribute("aria-label", name);
     const isRequired = this.category.kind === "NECESSARY";
 
     if (isRequired) {

packages/cookie-banner/src/components/preference-panel.ts

@@ -28,6 +28,7 @@ export class ProboPreferencePanel extends ProboElement {
     this.hidden = state !== "panel";
     if (state === "panel") {
       (this.root as ProboCookieBannerRoot).resetDraft();
+      this.focusFirst();
     }
   };
 

packages/cookie-banner/src/components/settings-button.ts

@@ -67,8 +67,8 @@ export class ProboSettingsButton extends HTMLElement {
         .icon { display: flex; flex-shrink: 0; }
         ::slotted(*) { display: contents; }
       </style>
-      <button part="button">
-        <span class="icon" part="icon">${COOKIE_ICON}</span>
+      <button part="button" aria-label="Cookie settings">
+        <span class="icon" part="icon" aria-hidden="true">${COOKIE_ICON}</span>
         <slot></slot>
       </button>
     `;

packages/cookie-banner/src/themed-banner/themed-banner.ts

@@ -17,8 +17,8 @@ import type { ProboCookieBannerRoot } from "../components/cookie-banner-root";
 import type { BannerConfig } from "../client";
 import { THEMED_STYLES } from "./styles";
 
-const CLOSE_ICON = `<svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><line x1="18" y1="6" x2="6" y2="18"/><line x1="6" y1="6" x2="18" y2="18"/></svg>`;
-const CHEVRON_DOWN = `<svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="6 9 12 15 18 9"/></svg>`;
+const CLOSE_ICON = `<svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><line x1="18" y1="6" x2="6" y2="18"/><line x1="6" y1="6" x2="18" y2="18"/></svg>`;
+const CHEVRON_DOWN = `<svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><polyline points="6 9 12 15 18 9"/></svg>`;
 
 export class ProboThemedBanner extends HTMLElement {
   private shadow: ShadowRoot;
@@ -52,9 +52,9 @@ export class ProboThemedBanner extends HTMLElement {
       <probo-cookie-banner-root banner-id="${this.esc(bannerId)}" base-url="${this.esc(baseUrl)}"${reopenAttr}>
         <probo-banner>
           <div class="floating" data-position="${this.esc(position)}">
-            <div class="card" role="dialog" aria-label="Cookie consent">
-              <p class="title">Cookie Preferences</p>
-              <p class="description" data-description>
+            <div class="card" role="dialog" aria-modal="true" aria-labelledby="probo-banner-title" aria-describedby="probo-banner-desc">
+              <p class="title" id="probo-banner-title">Cookie Preferences</p>
+              <p class="description" id="probo-banner-desc" data-description>
                 We use cookies to improve your experience and analyze site traffic.
               </p>
               <div class="buttons">
@@ -68,16 +68,16 @@ export class ProboThemedBanner extends HTMLElement {
 
         <probo-preference-panel>
           <div class="floating" data-position="${this.esc(position)}">
-            <div class="card" role="dialog" aria-label="Cookie preferences">
+            <div class="card" role="dialog" aria-modal="true" aria-labelledby="probo-panel-title">
               <div class="panel-header">
-                <p class="title" style="margin:0">Preferences</p>
+                <p class="title" id="probo-panel-title" style="margin:0">Preferences</p>
                 <button class="panel-close" data-action="back" aria-label="Close">
                   ${CLOSE_ICON}
                 </button>
               </div>
               <probo-category-list>
                 <template>
-                  <button class="cookie-toggle" data-action="toggle-cookies">
+                  <button class="cookie-toggle" data-action="toggle-cookies" aria-expanded="false" aria-label="Show cookie details">
                     ${CHEVRON_DOWN}
                   </button>
                   <div class="category-header">
@@ -141,6 +141,8 @@ export class ProboThemedBanner extends HTMLElement {
         cookieList.setAttribute("hidden", "");
         btn.classList.remove("open");
       }
+      btn.setAttribute("aria-expanded", String(open));
+      btn.setAttribute("aria-label", open ? "Hide cookie details" : "Show cookie details");
     });
   }
 
@@ -150,7 +152,7 @@ export class ProboThemedBanner extends HTMLElement {
 
     let html = "We use cookies to improve your experience and analyze site traffic.";
     if (config.privacy_policy_url) {
-      html += ` <a href="${this.esc(config.privacy_policy_url)}" target="_blank" rel="noopener">Privacy Policy</a>`;
+      html += ` <a href="${this.esc(config.privacy_policy_url)}" target="_blank" rel="noopener noreferrer">Privacy Policy</a>`;
     }
     el.innerHTML = html;
   }