Do the envelope and the pen have a different colors?
No, both the envelope and the pen are white.
    src        edge_attr  dst
0     0               on   11
1     0  to the right of    9
2     0             near   10
3     0   to the left of    3
4     1  to the right of    8
5     1   to the left of   14
6     1   to the left of    3
7     2               on   11
8     3               on   11
9     3  to the right of    0
10    3  to the right of    6
11    3  to the right of    1
12    4   to the left of   14
13    4   to the left of   10
14    4               on   11
15    4  to the right of    8
16    4   to the left of    7
17    4   to the left of    6
18    5               on   11
19    5  to the right of   15
20    6               on    7
21    6               on   11
22    6  to the right of   16
23    6   to the left of   10
24    6   to the left of    3
25    6  to the right of    4
26    7  to the right of    4
27    7   to the left of   14
28    8   to the left of    1
29    8   to the left of    4
30    9   to the left of    0
31   10          next to    0
32   10               on   11
33   10  to the right of    6
34   10  to the right of    4
35   14  to the right of    7
36   14  to the right of    4
37   14  to the right of    1
38   15   to the left of    5
39   15               on   11
40   16   to the left of    6
41   16               on   11