---
type: resource-type
title: UserPoolUICustomizationAttachment
description: aws resource type AWS::Cognito::UserPoolUICustomizationAttachment
name: UserPoolUICustomizationAttachment
lexicon: aws
resource_type: AWS::Cognito::UserPoolUICustomizationAttachment
---
`AWS::Cognito::UserPoolUICustomizationAttachment`, a resource type of the aws lexicon.

## Properties

- `ClientId` (`string`, required)
- `UserPoolId` (`string`, required)
- `CSS` (`string`, optional)