A white hanzi character in a black background box is 「仄 (zè)」。 A black character in white is 「平 (píng)」。 A gray background indicates the character can have multiple accents 「平」 or 「仄」 (The accent depends on the usage of the character)。 Rhyme characters are simultaneously highlighted in yellow when hovered. Green highlights are 「通韻」, that is, they have similar rhymes。 Red hanzi characters are currently not recognized by this software. You may try other variant characters.
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