Search condition Case Statement

SET SERVEROUTPUT ON SIZE 1000000;
DECLARE
n_salary EMPLOYEES.SALARY%TYPE;
n_emp_id EMPLOYEES.EMPLOYEE_ID%TYPE := 200;
v_msg VARCHAR(20);
BEGIN
SELECT salary INTO n_salary FROM employees WHERE employee_id = n_emp_id; CASE
WHEN n_salary < 2000 THEN
v_msg := 'Low';
WHEN n_salary >= 2000 AND n_salary <=3000
THEN
v_msg := 'Fair';
WHEN n_salary >= 3000 THEN
v_msg := 'High';
END CASE;

DBMS_OUTPUT.PUT_LINE(v_msg);

END;
/