Josie Natori found a challenge in resort season. “For clothes that look and feel just right for this long-selling season — from October to May — fabrics are so important. You can’t go from the richness of fall into limp clothes,” said the designer, who favored double-faced cotton, bonded jerseys and Neoprene to give body to her looks. She showed suits and sporty separates — “toppers,” which Natori insisted “are a must for the season,” with lean, slightly cropped pants and sleeveless sheaths, and hip-length jackets with short, flippy skirts. All were in black and white, sometimes mixed but often monotone with an occasional pop of chartreuse. Natori more than met that resort-season challenge with a chic, refined collection.