完善 ip 提取功能，优化更新主题样式

src/app/(auth)/login/captcha.tsx

@@ -53,7 +53,7 @@ export default function Captcha(props: CaptchaProps) {
               onClick={refreshCaptcha}
             />
             <Button
-              variant="outline"
+              theme="outline"
               onClick={refreshCaptcha}
               className="text-sm"
             >
@@ -69,7 +69,7 @@ export default function Captcha(props: CaptchaProps) {
         </div>
         <DialogFooter>
           <Button
-            variant="outline"
+            theme="outline"
             onClick={() => setShowCaptcha(false)}
             className="mr-2"
           >

src/app/(auth)/login/page.tsx

@@ -229,7 +229,7 @@ export default function LoginPage(props: LoginPageProps) {
                   />
                   <Button
                     type="button"
-                    variant="outline"
+                    theme="outline"
                     className="whitespace-nowrap h-12"
                     onClick={checkUsername}
                     disabled={countdown > 0}
@@ -259,7 +259,7 @@ export default function LoginPage(props: LoginPageProps) {
               <Button
                 className="w-full h-12 text-lg"
                 type="submit"
-                variant="gradient"
+                theme="gradient"
                 disabled={submitting}
               >
                 {submitting ? '登录中...' : '注册 / 登录'}