Cascading Style Sheets
Cascading Style Sheets (CSS) is a style sheet language used for describing the presentation of a document written in a markup language such as HTML. CSS is a cornerstone technology of the World Wide Web, alongside HTML and JavaScript.
A small delay CSS
When loading the page, it may take some time before all the CSS is loaded. There is a high chance that your web visitors will see the non-styled page for a second. Hide your elements, and show after it is fully ready. Use .preload classes with none display style, link-preload will do the rest.
<!DOCTYPE html>
<html>
<head>
...
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/link-preload@latest/link-preload.js"></script>
...
</head>
<body class="preload" style="display: none;">
...
</body>
</html>