John, in his Gospel, loves the motifs of light and dark. Nicodemus came to Jesus at night. When Judas slipped out of the last supper to betray Jesus, it was night.
John's account of the empty tomb records Mary Magdalene going to the tomb "while it was still dark".
This worries a few people, but it need not.
The worry is that Mark records 3 women going to the tomb "just after sunrise". He seems to want to highlight the fact that it was day time, so they could see where they were going and what they were witnessing. … Read more about Come and have breakfast