react-katex don't work

[Rick]

code below:

import 'katex/dist/katex.min.css';
import { InlineMath, BlockMath } from 'react-katex';
render() {
return(<BlockMath>\int_0^\infty x^2 dx</BlockMath>)
}

output:

[Rick]

sorry! I don't add katex js resource