> ## Documentation Index > Fetch the complete documentation index at: https://constanza101-borrissol-28.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Google Analytics 4 with Consent Mode v2 in Borrissol > How Borrissol implements GA4 with Consent Mode v2 Advanced: cookieless default, cookie banner, localStorage persistence, and denied-state modeling. Google Analytics 4 loads on every visit to borrissol.com via `gtag.js`, but it operates in a cookieless mode by default. Cookies are only set after the visitor explicitly clicks **Accept** on the cookie banner. This is achieved through Google Consent Mode v2 Advanced — the most privacy-preserving GA4 integration pattern available, and the one required for full GDPR compliance in EU markets like Spain and France. ## How Consent Mode v2 works in this project Consent Mode v2 separates the GA4 **loading** decision (always load) from the **cookie** decision (only set after consent). The flow on every page visit is: Before the GA4 snippet loads, `Layout.astro` initializes Consent Mode with all storage types set to `denied`. This is the "Advanced" pattern: the script loads, but Google is explicitly told it may not write cookies or read device storage. ```js theme={null} window.dataLayer = window.dataLayer || []; function gtag() { dataLayer.push(arguments); } // Must run BEFORE the GA4 snippet gtag('consent', 'default', { analytics_storage: 'denied', ad_storage: 'denied', ad_user_data: 'denied', ad_personalization: 'denied', wait_for_update: 500, }); ``` The GA4 measurement script loads in the `` of every page via `Layout.astro`. In denied state it fires a cookieless ping — Google uses this to model anonymous, aggregate traffic data without storing any PII. `CookieBanner.astro` checks `localStorage` for a previously saved consent decision. If no value is found, the banner is displayed with two actions: **Accept** and **Decline**. When the visitor clicks **Accept**, the banner calls `gtag('consent', 'update', { analytics_storage: 'granted' })` and saves `'accepted'` to `localStorage`. GA4 then sets its measurement cookies and begins full tracking for that session and all future sessions. When the visitor clicks **Decline**, `'rejected'` is saved to `localStorage`. The banner is dismissed and GA4 continues in cookieless mode for all future visits. On every page load, `Layout.astro` reads `localStorage` inside the same inline script that sets the consent default. If the saved value is `'accepted'`, it calls `gtag('consent', 'update', { analytics_storage: 'granted' })` immediately — before the GA4 snippet fires — so returning visitors never see the banner again and GA4 operates in full mode from the first pageview. `CookieBanner.astro` also reads `localStorage` independently to decide whether to show the banner at all. ## The cookie banner (`CookieBanner.astro`) The banner is a minimal two-button component rendered server-side by Astro and activated client-side: * **Accept** — updates consent to `granted`, saves `'accepted'` to `localStorage`, hides the banner * **Decline** — saves `'rejected'` to `localStorage`, keeps GA4 in cookieless mode, hides the banner No cookies are read or written before the user makes a choice. The banner's state is persisted entirely in `localStorage`, not in a cookie itself — keeping the pre-consent state clean. The privacy policy text visible in `PrivacySection.astro` is translated for all four languages via `ui.ts`. The keys `cookie.accept`, `cookie.decline`, `cookie.text`, and `privacy.*` cover all banner and policy copy. ## Layout.astro integration `Layout.astro` is responsible for the correct script ordering in ``: 1. Consent Mode default initialization (inline `