Looks fine to me, but I never saw it before.
Most likely cause: accidentally hitting a Zoom button in your browser.
Your site width is being limited by this CSS:
body.custom-background div.site {
max-width: 1320px;
margin: 0 auto;
}
So what do I change it to?
My browser is not zoomed in at all. So is the CSS what needs to changed for the header to adjust to cover the screen?
And the background picture on the other pages are all full-size. It’s just the home page that is shrunk.
Since Tesseract is a commercial product you should post your question with the vendor’s support for help with customizations and issues:
https://themeforest.net/item/tesseract-multipurpose-wordpress-theme/13544524/support
These forums are for support of themes available in the wordpress.org repository and the volunteers on this forum don’t have access to commercial products. Contacting the vendor also allows the developers to be aware of potential issues with their products.
