Hey e.,
this is not an error, rather an intended behaviour – on masonry pages the content area with tiles is wider than the header since each tile has a margin all around it, yet the content area does not have a background color by design, so the header needs to be slightly thinner to remain in line with the edges of the first and last tiles in a row.
In your situation, since you’ve declared a background on the tile content area, you can expand the header width to fit the former, by editing one line in the theme’s “custom-styles.php” file (located in the main theme folder):
on line 102, replace the “$finalwidthheader” with “$finalwidthheadernp”, i.e. replace
#header-box { max-width: px !important; }
with:
#header-box { max-width: px !important; }
Please let me know if achieves the desired effect!
Sincerely,
Andrii / Satori Studio