Is there a way to change the color of the login page button?

Hi!

I am playing around Mobile Freedom in 8.3.2 and tried adding a crt.RunBusinessProcessRequest for a button but did not work. Is there no way of doing that?

I found this in the article > 2nd paragraph > last sentence and base my test on it: Both main Creatio app and Creatio Mobile have the same request handlers.

Here's my sample code:
**Mobile run on Online Mode.

		{
			"operation": "insert",
			"name": "Button_5yi1e6m",
			"values": {
				"type": "crt.Button",
				"caption": "#ResourceString(Button_5yi1e6m_caption)#",
				"color": "warn",
				"disabled": false,
				"size": "large",
				"iconPosition": "only-text",
				"visible": true,
				"clicked": {
					"request": "crt.RunBusinessProcessRequest",
					"params": {
						"processName": "UsrProcessName",
						"processRunType": "ForTheSelectedPage",
						"saveAtProcessStart": true,
						"showNotification": true,
						"recordIdProcessParameterName": "ppRecordId"
					}
				},
				"clickMode": "default"
			},
			"parentName": "FlexContainer_mx2730x",
			"propertyName": "items",
			"index": 1
		},	

I need to create a multi value field based on lookup.

The only solution I found is https://customerfx.com/tool/multi-select-text-field/. 
But it seems to work only with classic UI.

Is there a solution with Freedom UI ?