Though the movie is set in 1959 the markings on the center line of the highway are yellow. Such lines were white until 1971 when the Manual of Uniform Traffic Control Devices mandated a switch to yellow.
Toward the end of the movie, when Vivian and her divorce lawyer are walking down the steps of the courthouse, you can see an older woman with a straw hat walk up the stairs by them. When Vivian & the lawyer reach the door to walk outside, you can see the same woman walking in.