This happen because the CSS is loaded over HTTPS protocol and you accessing the website with HTTP protocol,
You can fix this with forcing user to use HTTPS, on .htaccess write:
RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
1
solved Problems with CSS search results on web sites [closed]