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+<!DOCTYPE html>
+<html lang="nb" data-theme="dark">
+<head>
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1">
+  <title>ms-ai-architect — Playground v3</title>
+
+  <!-- Vendored design-system. Kilden er shared/playground-design-system/ — synces via
+       scripts/sync-design-system.mjs ved marketplace-rot. Aldri rediger filer under
+       playground/vendor/ direkte; endringer går i shared/ + re-sync. -->
+  <link rel="stylesheet" href="vendor/playground-design-system/fonts.css">
+  <link rel="stylesheet" href="vendor/playground-design-system/tokens.css">
+  <link rel="stylesheet" href="vendor/playground-design-system/base.css">
+  <link rel="stylesheet" href="vendor/playground-design-system/components.css">
+  <link rel="stylesheet" href="vendor/playground-design-system/components-tier2.css">
+  <link rel="stylesheet" href="vendor/playground-design-system/components-tier3.css">
+  <link rel="stylesheet" href="vendor/playground-design-system/components-tier3-supplement.css">
+</head>
+<body>
+  <!-- Walking-skeleton: 4 placeholder-overflater. Step 5-7 fyller dem ut.
+       Bare én av disse er aktiv om gangen via state.activeSurface. -->
+  <main id="app">
+    <section id="surface-onboarding" data-surface="onboarding" hidden></section>
+    <section id="surface-home" data-surface="home" hidden></section>
+    <section id="surface-catalog" data-surface="catalog" hidden></section>
+    <section id="surface-project" data-surface="project" hidden></section>
+  </main>
+
+  <!--
+    Klassisk script (ikke type="module") av to grunner:
+      1. External <script type="module" src="..."> feiler på file:// i Chrome+Firefox
+         (ref WHATWG html#8121, Chromium 41378227).
+      2. Single-file deployment per brief Constraints — ingen build-step.
+    Kommende steps utvider IIFE-en under: Step 2 (state-modul), Step 3 (eksport/import),
+    Step 4 (CATALOG), osv.
+  -->
+  <script>
+  (function () {
+    'use strict';
+
+    // localStorage-nøkkel og schema-versjon. Endring av STATE_KEY krever migrasjons-steg
+    // (se Step 3 — MIGRATIONS-pipeline). SCHEMA_VERSION bumpes ved breaking endringer
+    // i state-form og driver eager migrations ved import.
+    const STATE_KEY = 'ms-ai-architect-state-v1';
+    const SCHEMA_VERSION = 1;
+
+    // Eksponer som globals for Verify-asserts og DevTools-debugging. Senere steps
+    // utvider window.__-namespace med __store, __CATALOG, __PARSERS, __RENDERERS,
+    // __buildCommand, __buildEnvelope, __handlePasteImport.
+    window.__STATE_KEY = STATE_KEY;
+    window.__SCHEMA_VERSION = SCHEMA_VERSION;
+  })();
+  </script>
+</body>
+</html>
