Flags switching position before the page fully loads

Hello, and thank you for the great plugin.

One question: My flags seem to be changing position before the page fully loads. (It is visible only in internet explorer, safari, firefox, not chrome). I have created a custom widget area in my theme in order for them to appear in the header and I edited the style via css:

.lang-item {
display: inline;
float:left;
width:40px;
margin: 0px;
padding: 0px;
position: relative;
top: 16px; left: 223px;
z-index: 10;

My website in opensolution.gr

Could you suggest any solutions?

https://www.ads-software.com/extend/plugins/polylang/