It is accidental about why the LOGO was changed to Roman numerals in the second season, because some TV dramas like to use Roman numerals, while others like to have Arabic numerals. But at that time, the official found that the Roman numeral 3 was too big, which would affect the overall beauty, and it was possible to shoot love 4567 in the future. It will be a long time until 8 o'clock, and not everyone knows Roman numerals, which will cause inconvenience, so the official decided to change it to Arabic numerals.
And now most TV series with sequels are rectifying into Arabic numerals.
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