During the work on moving the page from PHP 5.3 to PHP 7.1 there was a problem with the appearance of the site. The page is moved from the top by 17-18 pixels. I can not find a reason. I want the page to look like before.
Please help.
On website there is a PHP 7.1 before was 5.6
screenshot how it was before (ok) and after (bad)
<body>
<div id="container">
<div id="header">
<a href="https://www.facebook.com/Gminny.Osrodek.Kultury.w.Babimoscie" title="" target="_blank">
<img src="https://i.stack.imgur.com/GEU4r.jpg" alt="Jesteśmy na Facebook" title="" />
</a>
</div>
<div id="mainnav">
<div class="nav-container-outer">
<ul id="nav-container" class="nav-container">
...
</ul>
</div>
</div>
</div>
</body>
How to Back to previous appearance