diff --git a/apps/reader/src/NativeSignIn.tsx b/apps/reader/src/NativeSignIn.tsx
index 47a5441..67404d4 100644
--- a/apps/reader/src/NativeSignIn.tsx
+++ b/apps/reader/src/NativeSignIn.tsx
@@ -116,7 +116,7 @@ function NativeSignInView({ binding, onSignedOut }: NativeSignInProps): JSX.Elem
         <div className="connection-actions">
           {view.waiting ? (
             <button
-              className="text-action"
+              className="mdbase-button"
               type="button"
               disabled={working}
               onClick={() => void act(authorize)}
@@ -125,7 +125,7 @@ function NativeSignInView({ binding, onSignedOut }: NativeSignInProps): JSX.Elem
             </button>
           ) : !view.paired || view.error ? (
             <button
-              className="connection-connect"
+              className="mdbase-connect-action"
               type="button"
               disabled={working || view.disabled}
               onClick={() => void act(authorize)}
@@ -135,7 +135,7 @@ function NativeSignInView({ binding, onSignedOut }: NativeSignInProps): JSX.Elem
           ) : null}
           {view.paired ? (
             <button
-              className="text-action"
+              className="mdbase-button"
               type="button"
               disabled={working}
               onClick={() => void act(signOut)}
@@ -145,7 +145,7 @@ function NativeSignInView({ binding, onSignedOut }: NativeSignInProps): JSX.Elem
           ) : null}
           {snapshot.selectedCollectionId ? (
             <button
-              className="text-action"
+              className="mdbase-button"
               type="button"
               disabled={working}
               onClick={() => {
diff --git a/docs/new-sdk.md b/docs/new-sdk.md
index fa88daa..c9279f6 100644
--- a/docs/new-sdk.md
+++ b/docs/new-sdk.md
@@ -84,7 +84,9 @@ it does not guess them or replace the default Connect/extension runtimes.
 
 Sign in reserves the tab in the user gesture before asynchronous SDK start or
 expiry renewal. The SDK owns approval detection and protected state. The UI uses
-canonical status/email, reopen-tab, popup-blocked and interrupted wording. It
+canonical status/email, reopen-tab, popup-blocked and interrupted wording. Sign-in
+and secondary actions reuse Reader's existing shared control styles, including
+usable touch targets at 390px. It
 shows only states the SDK can distinguish, not a fabricated decline or setup
 result. Sign out waits for SDK close; it is local shutdown, not membership
 revocation or protected-store deletion. Forget uses the actual selected SDK ID.