原创网页元素截图练习 / Original page-element capture exercise
200x100 CSS tile. Device1=200x100,device2=400x200,css2=200x100 PNG.
固定页面与800x600视口，比较输出比例，不代表每种系统截图程序。
Same original page and800x600viewport; capture settings differ. No universal screenshot-app or physical-device claim.
