i need a bright strapless gradutation dress

Not sure if you would like a short or long one but there is some very cute bright strapless dresses out there for your graduation.  If you are a purple fan check out this wispy layers of tulle that screate the baby doll styling of this fabulous semi formal Prom party dress. Four layers of fabric give the skirt volume. Large sequin Pailettes sewn onto the bodice and the sprinkled onto the skirt front sparkle with glamour.
Purple strapless dress is designed to be slightly above the knee- 28 inches in length from under the arm to hemline.

Another great choice might be the dress by Shelli Segal which is a strapless long dress.  It has a gorgeous column of silk charmeuse is fashioned with a strapless sweetheart bust, beautifully ruched and set off with a fan-shaped ray of gathers that ease the fit through the bodice.

Hope you like some of the choices I have included and Congratulations on your graduation!