爐火純青 [炉－纯－]

Jyutping lou4 fo2 seon4 cing1
Pinyin lú huǒ chún qīng

Definitions (CC-CEDICT)
  1. lit. the stove fire has turned bright green (allusion to Daoist alchemy) (idiom)
  2. fig. (of an art, a technique etc) brought to the point of perfection
Definitions (粵典–words.hk)
  1. x
Definitions (Wiktionary)
  1. phrase, idiomatic
    to have reached high perfection or complete mastery
Examples (Wiktionary)
  1. Mandarin
    2021年1月，英国广播公司（BBC）拍摄的纪录片《重返湖北》中，中国网友见识到了英媒的“滤镜”用得有多炉火纯青。片中的武汉一副灰暗，不少中国网友吐槽BBC使用了“阴间滤镜”。
    2021年1月，英國廣播公司（BBC）拍攝的紀錄片《重返湖北》中，中國網友見識到了英媒的“濾鏡”用得有多爐火純青。片中的武漢一副灰暗，不少中國網友吐槽BBC使用了“陰間濾鏡”。
    ２０２１ nián １ yuè ， yīng guó guǎng bō gōng sī （ ＢＢＣ ） pāi shè de jì lù piàn “ chóng fǎn hú běi ” zhōng ， zhōng guó wǎng yǒu jiàn shí dào le yīng méi de “ lǜ jìng ” yòng de yǒu duō lú huǒ chún qīng ． piàn zhōng de wǔ hàn yī fù huī àn ， bù shǎo zhōng guó wǎng yǒu tù cáo ＢＢＣ shǐ yòng le “ yīn jiān lǜ jìng ” ．
    • In January 2021, Chinese netizens became aware of how skilled British mass media were at their utilising "filters" from Returning to Hubei, a documentary by British Broadcasting Company (BBC). In the documentary, Wuhan was dark as midnight, leading many Chinese netizens criticising that BBC used "a filter from the hell".