Resize Corner Handle

Resize corner handle, one slim smooth rounded stroke 0.004 m thick framing a lower-right window corner, about 0.05 m each way (rotated by the buyer for other corners); profile is arc or L. Accent glows along it. Hover lengthens it slightly and glows.

风格：low-poly, flat-shaded vertex colors, no textures, 2 materials: the shared opaque one plus a distinct surface (glass, water or chrome), which stays its own mesh through mergeAssets rather than merging into the rest; shares palette and scale with its kit