Correct

炉火纯青

/ lúhuǒ chún qīng /
Strokes

Definition

lit. the stove fire has turned bright green (allusion to Daoist alchemy) (idiom)/fig. (of an art, a technique etc) brought to the point of perfection

Example

Definition

the stove fire (for making pills of immortality) begins to glow a pure blue―attain a high degree of perfection; reach the acme of perfection

1
de
shānshuǐhuà
山水画
技法
dào
达到
huǒchúnqīng
炉火纯青
de
jìngjiè
境界
  

His skill in landscape painting was honed to perfection. / He attained the acme of perfection in landscape painting.

2
dào
达到
huǒchúnqīng
炉火纯青
de
地步

reach high excellence