This is the 17412th most frequent Russian word.
теплого
"Теплого" means "warm" in English (genitive or accusative case of "тёплый").
In this sentence, 'теплого' is used in the genitive case to describe the tea, indicating that the tea is warm.
Я хочу чашку теплого чая.
I want a cup of warm tea.
Here, 'теплого' is used as a descriptive adjective in the genitive case to modify 'цвета,' denoting a warm tone.
В теплого цвета покрывале ей спалось спокойнее.
In the warm-colored blanket, she slept more calmly.
In this instance, 'теплого' modifies 'огня' in the genitive case to describe it as warm.