SELECT CASE WHEN PERSO_DAT > add_months(sysdate, 3) then
'<div style="background-color:green;"> '|| PERSO_DAT ||' </div>'
WHEN PERSO_DAT BETWEEN ADD_MONTHS(SYSDATE,+3) and ADD_MONTHS(SYSDATE,+1)then '<div style="background-color:blue;"> '|| PERSO_DAT ||' </div>'
WHEN PERSO_DAT < add_months(sysdate, 1) then
'<div style="background-color:red;"> '|| PERSO_DAT ||' </div>'
ELSE
to_char(PERSO_DAT)
END PERSO_DAT
FROM MA