YOU SAID:
her bright cerulean eyes sparkled in the natural light
INTO JAPANESE
彼女の明るいセルリアンの目は自然光の中で輝いていました
BACK INTO ENGLISH
Her bright Cerulean eyes were shining in natural light
INTO JAPANESE
彼女の明るいセルリアンの目は自然光で輝いていました
BACK INTO ENGLISH
Her bright Cerulean eyes were shining in natural light
That didn't even make that much sense in English.