diff --git a/app/globals.css b/app/globals.css
index 06cbc06..95296a6 100644
--- a/app/globals.css
+++ b/app/globals.css
@@ -936,9 +936,15 @@ html[data-route-scope='drive'] body {
   }
 }
 
+.ultimail-login-connect-action {
+  display: flex;
+  width: 100%;
+  justify-content: center;
+}
+
 .ultimail-login .ultimail-login-connect-border {
   position: relative;
-  display: inline-flex;
+  display: flex;
   width: 100%;
   padding: 2px;
   border-radius: 9999px;
@@ -1163,6 +1169,11 @@ html[data-route-scope='drive'] body {
   .ultimail-login .ultimail-login-connect-border {
     width: auto;
   }
+
+  .ultimail-login-connect-action .ultimail-login-connect-border,
+  .ultimail-login-card-frame .ultimail-login-connect-border {
+    width: 100%;
+  }
 }
 
 @media (prefers-reduced-motion: reduce) {
diff --git a/components/auth/auth-connect-button.tsx b/components/auth/auth-connect-button.tsx
new file mode 100644
index 0000000..2370cc3
--- /dev/null
+++ b/components/auth/auth-connect-button.tsx
@@ -0,0 +1,66 @@
+"use client"
+
+import Link from "next/link"
+import { cn } from "@/lib/utils"
+
+type AuthConnectButtonCommon = {
+  children: React.ReactNode
+  className?: string
+}
+
+type AuthConnectButtonAsButton = AuthConnectButtonCommon &
+  React.ButtonHTMLAttributes<HTMLButtonElement> & {
+    href?: undefined
+  }
+
+type AuthConnectButtonAsAnchor = AuthConnectButtonCommon &
+  React.AnchorHTMLAttributes<HTMLAnchorElement> & {
+    href: string
+  }
+
+type AuthConnectButtonAsLink = AuthConnectButtonCommon &
+  Omit<React.ComponentProps<typeof Link>, "href"> & {
+    href: string
+    as: "link"
+  }
+
+export type AuthConnectButtonProps =
+  | AuthConnectButtonAsButton
+  | AuthConnectButtonAsAnchor
+  | AuthConnectButtonAsLink
+
+/** UltiSpace gradient CTA — full width, centered in auth flows. */
+export function AuthConnectButton(props: AuthConnectButtonProps) {
+  const { children, className } = props
+  const btnClass = cn("ultimail-login-connect-btn w-full", className)
+
+  let control: React.ReactNode
+  if ("as" in props && props.as === "link") {
+    const { as: _as, href, className: _c, children: _ch, ...linkProps } = props
+    control = (
+      <Link href={href} className={btnClass} {...linkProps}>
+        {children}
+      </Link>
+    )
+  } else if ("href" in props && props.href) {
+    const { href, className: _c, children: _ch, ...anchorProps } = props
+    control = (
+      <a href={href} className={btnClass} {...anchorProps}>
+        {children}
+      </a>
+    )
+  } else {
+    const { className: _c, children: _ch, ...buttonProps } = props
+    control = (
+      <button className={btnClass} {...buttonProps}>
+        {children}
+      </button>
+    )
+  }
+
+  return (
+    <div className="ultimail-login-connect-action">
+      <div className="ultimail-login-connect-border">{control}</div>
+    </div>
+  )
+}
diff --git a/components/auth/auth-flow-page.tsx b/components/auth/auth-flow-page.tsx
index 9f0b829..de337b7 100644
--- a/components/auth/auth-flow-page.tsx
+++ b/components/auth/auth-flow-page.tsx
@@ -1,9 +1,9 @@
 "use client"
 
 import { useCallback, useEffect, useMemo, useState } from "react"
-import Link from "next/link"
 import { Loader2 } from "lucide-react"
 import { AuthCard } from "@/components/auth/auth-card"
+import { AuthConnectButton } from "@/components/auth/auth-connect-button"
 import { FlowChallengeForm } from "@/components/auth/flow-challenge-form"
 import {
   AUTH_FLOW_SLUGS,
@@ -131,17 +131,15 @@ export function AuthFlowPage({
               Redirection en cours…
             </p>
           ) : null}
-          <div className="ultimail-login-connect-border w-full">
-            {successExternal ? (
-              <a href={successHref} className="ultimail-login-connect-btn">
-                {successActionLabel}
-              </a>
-            ) : (
-              <Link href={successHref} className="ultimail-login-connect-btn">
-                {successActionLabel}
-              </Link>
-            )}
-          </div>
+          {successExternal ? (
+            <AuthConnectButton href={successHref}>
+              {successActionLabel}
+            </AuthConnectButton>
+          ) : (
+            <AuthConnectButton as="link" href={successHref}>
+              {successActionLabel}
+            </AuthConnectButton>
+          )}
         </div>
       ) : (
         <FlowChallengeForm
diff --git a/components/auth/flow-challenge-form.tsx b/components/auth/flow-challenge-form.tsx
index 6f1b64f..1db4012 100644
--- a/components/auth/flow-challenge-form.tsx
+++ b/components/auth/flow-challenge-form.tsx
@@ -2,6 +2,7 @@
 
 import { useEffect, useMemo, useRef, useState } from "react"
 import { Loader2 } from "lucide-react"
+import { AuthConnectButton } from "@/components/auth/auth-connect-button"
 import { Input } from "@/components/ui/input"
 import { Label } from "@/components/ui/label"
 import type { FlowChallenge } from "@/lib/auth/flow-api"
@@ -151,22 +152,20 @@ export function FlowChallengeForm({
       ) : null}
 
       {isKnownComponent(component) ? (
-        <div className="ultimail-login-connect-border pt-1">
-          <button
-            type="submit"
-            disabled={submitting}
-            className="ultimail-login-connect-btn w-full disabled:opacity-60"
-          >
-            {submitting ? (
-              <>
-                <Loader2 className="size-4 animate-spin" aria-hidden />
-                <span>Patientez…</span>
-              </>
-            ) : (
-              primaryAction
-            )}
-          </button>
-        </div>
+        <AuthConnectButton
+          type="submit"
+          disabled={submitting}
+          className="disabled:opacity-60"
+        >
+          {submitting ? (
+            <>
+              <Loader2 className="size-4 animate-spin" aria-hidden />
+              <span>Patientez…</span>
+            </>
+          ) : (
+            primaryAction
+          )}
+        </AuthConnectButton>
       ) : null}
     </form>
   )
diff --git a/components/auth/login-form.tsx b/components/auth/login-form.tsx
index c5101c1..e3b48f5 100644
--- a/components/auth/login-form.tsx
+++ b/components/auth/login-form.tsx
@@ -1,8 +1,8 @@
 "use client"
 
-import Link from "next/link"
 import { Sparkles } from "lucide-react"
 import { AuthCard } from "@/components/auth/auth-card"
+import { AuthConnectButton } from "@/components/auth/auth-connect-button"
 
 type LoginFormProps = {
   loginHref: string
@@ -25,26 +25,22 @@ export function LoginForm({
         <div className="flex w-full flex-col gap-3 text-center text-sm text-muted-foreground">
           <p>
             Pas encore de compte ?{" "}
-            <Link className="font-medium text-primary underline" href={signupHref}>
+            <a className="font-medium text-primary underline" href={signupHref}>
               Créer un compte
-            </Link>
+            </a>
           </p>
           <p>
-            <Link className="font-medium text-primary underline" href={forgotPasswordHref}>
+            <a className="font-medium text-primary underline" href={forgotPasswordHref}>
               Mot de passe oublié ?
-            </Link>
+            </a>
           </p>
         </div>
       }
     >
-      <div className="flex justify-center">
-        <div className="ultimail-login-connect-border w-full">
-          <a href={loginHref} className="ultimail-login-connect-btn">
-            <Sparkles className="size-4 shrink-0" strokeWidth={2} aria-hidden />
-            Se connecter avec UltiSpace
-          </a>
-        </div>
-      </div>
+      <AuthConnectButton href={loginHref}>
+        <Sparkles className="size-4 shrink-0" strokeWidth={2} aria-hidden />
+        Se connecter avec UltiSpace
+      </AuthConnectButton>
     </AuthCard>
   )
 }