Tengo un error con "Comparator cannot be resolved or is not a field"

package br.com.alura;

import java.util.ArrayList;

import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.stream.Collectors;

public class Clase5 {

    public static void main(String[] args) {

        ArrayList<Curso> cursos = new ArrayList<>();

        cursos.add(new Curso ("PHP", 20));
        cursos.add(new Curso ("Ruby", 50));
        cursos.add(new Curso ("JavaScript", 10));
        cursos.add(new Curso ("Java", 30));

        System.out.println(cursos);

        //cursos.sort(Comparator.comparing(Curso::getNombre));
        Collections.sort(cursos.Comparator.comparing(Curso::getNombre));

        System.out.println(cursos);
    }
}