diff --git a/scripts/dev/stub-idp.js b/scripts/dev/stub-idp.js
index b701a3d..0046272 100644
--- a/scripts/dev/stub-idp.js
+++ b/scripts/dev/stub-idp.js
@@ -56,7 +56,7 @@ function pickerPage(query) {
     q.set('login_as', p.sub)
     return `<li><a href="/authorize?${q.toString()}">${p.name} &lt;${p.email}&gt; <code>${p.sub}</code></a></li>`
   }).join('\n')
-  return `<!doctype html><meta charset="utf-8"><title>Stub IdP</title>
+  return `<!doctype html><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1"><title>Stub IdP</title>
 <style>body{font:16px system-ui;margin:3rem auto;max-width:34rem}a{display:block;padding:.6rem;border:1px solid #ccc;border-radius:8px;margin:.4rem 0;text-decoration:none;color:#123}code{color:#888}</style>
 <h1>Stub IdP — choose a test account</h1>
 <p>DEV ONLY. Signs you in as the selected pre-linked identity.</p>
