ReactiveSearch components accept a prop innerProps which can be utilized for passing props to internal components as specified in the Props section of each component.
Usage
You can pass an object via the innerprops prop to pass additonal props like:
innerProps={{
    icon: {
        ...
    },
    button: {
        ...
    }
}}Examples
This example uses the innerProps prop to pass some additional props to the internal Icon component of TextField.
<TextField
    ...
    innerprops={{        icon: {            color: 'tomato',            fontSize: 13        }    }}/>