Submenu and divider

Dear Support Team,

I have two questions for the https://emmerams-muehle.de/nachbarschaftsaktion/ website that I can’t get any further with:

1. see screenshot: https://emmerams-muehle.de/support/1.jpg
Why does the submenu protrude beyond the layout edge? And what can I do to make it appear left-aligned with the logo and other content?

2. see screenshot: https://emmerams-muehle.de/support/2.jpg
Further down the page (center) I have inserted a “dividing line across the entire width” between the articles: But this is displayed twice: Why? And what can I do so that it only appears once? Can I also set the color tone darker?

Best regards, Diana

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