NEW YORK — Long known for its collections of wearable and stylish basics, Banana Republic put on its first runway show on Thursday night. The spring styles were a departure from those of the brand’s origins — a catalogue of khaki-laden travel gear. The firm, of course, had expanded beyond those years ago. This season, there were feminine looks with a hint of the Fifties, but with a modern spin. Here, for example, is Banana Republic’s houndstooth cotton coat worn over a silk chiffon top, silk charmeuse camisole and cotton denim cargo pants. For more on the presentation, see story Fashion Republic.