一杯咖啡，只有热气在动

Create a 6-frame looping animation sprite sheet, 3 columns by 2 rows of equal 512x512 cells on a flat warm terracotta background. Subject: a simple white ceramic cup of black coffee on a matching saucer, flat gouache illustration with soft grain. The cup never moves or changes between cells. Only two thin ribbons of pale steam rise and curl, drifting upward a little more in each cell so that frame 6 flows back into frame 1. Keep the cup centered at the same coordinates in every cell. No grid lines, no numbers, no text, no watermark.

生成 6 帧循环动画精灵图，3 列 2 行，每格 512x512，纯赤陶色背景。主体是放在同款碟子上的白瓷杯，杯中是黑咖啡，平面水粉插画带细颗粒。杯子在每格位置完全不变，只有两缕细白蒸汽升起并卷曲，每格再往上飘一点，第 6 帧接回第 1 帧。不要格线、数字、文字和水印。