[styled-components]theme

App.tsx

import { useEffect } from 'react'
import styled from 'styled-components'
import { useTheme } from './util/Theme'

const Text = styled.div`
  color: ${p => p.theme.color};
`
const App = () => {
  const { setColor } = useTheme()

  // APIなどからスタイルを取得した後にsetColorに値を渡す
  useEffect(() => setColor('red'), [setColor])

  return (
    <Text>Theme sample</Text>
  )
}

export default App