Can anyone tell me why before not working on styled components?

Question

I'm try to use before on style components on React but it's not working. Without before background image shown but after adding this before background image not showing;

import styled from  'styled-components'
export const Container=styled.div `
&:before {
content:'';
top:0px;
left:0px;
right:0px;
position:absolute;
background-image:url(${({bg})=>bg});
background-size:cover;
}
`;

Answer 1

try::before with double ":" Also give some height/width