Do your best / good luck / hang in there.
Said to anyone facing something difficult. 頑張ります is "I'll do my best," the standard thing to say when given a task. 頑張れ is the shouted, cheering version. It is about effort rather than luck, which is a real window into the culture.
To someone already exhausted it can land as pressure — "try harder." Japanese speakers switch to 無理しないで (don't overdo it) in that case.
Reading a definition isn't the same as saying it to someone. Lingo Kaiava is a voice tutor set to Japanese — it uses 頑張って the way locals do, corrects you in the moment, and never "fixes" the way real people actually talk into textbook Japanese.
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