There was an almost-full light circle and a sliver of dark circle left over.

有一个几乎完整的光圈和剩下的一条黑色圆圈。

Just take the half of a dark circle and half of a light circle left over from the first quarter moon you made.

只取你制作的第一弦月留下的半个黑圈和半个亮圈。