clientId) or for all clients (by setting the clientId to ALL). If you specify ALL, the default configuration is used for every client that has no previously set UI customization. If you specify UI customization settings for a particular client, it will no longer return to the ALL configuration.curl --location --request POST '/' \
--header 'X-Amz-Target;' \
--header 'Content-Type: application/json' \
--data-raw '{
"UserPoolId": "string",
"ClientId": "string",
"CSS": "string",
"ImageFile": "string"
}'{
"UICustomization": {
"UserPoolId": "string",
"ClientId": "string",
"ImageUrl": "string",
"CSS": "string",
"CSSVersion": "string",
"LastModifiedDate": "string",
"CreationDate": "string"
}
}