可换变量其实很少：
{
"topic": "library | garden | lab | recycle",
"main_text": "KEEP IT QUIET",
"tag": "library",
"hero_prop": "open book",
"characters": "two students",
"micro_signs": ["SHHH", "QUIET", "LIBRARY CARD"],
"accent_symbol": "lightning / sprout / recycle arrow",
"aspect_ratio": "16:9"
}
只换 topic / main_text / prop / 小告示。
不要换标题骨架、边框、角色比例和材料感。