How to Defer Loading Large CSS Files for Optimized Website Performance?

Enhance CSS Delivery by Deferring Loading of Large CSS Files

Google's documentation for developers advises optimizing CSS delivery to improve website performance. One of the recommended strategies is inlining critical CSS in the head, while loading the original, larger CSS file after page onload.

Loading Large CSS Files After Page Onload

The provided example effectively handles the inlining of a small CSS file, but leaves questions about how to approach larger CSS files.

To defer loading of a large CSS file until after page onload, you can utilize code snippets like the following:

<code class="javascript">function loadStyleSheet(src) {
    if (document.createStyleSheet){
        document.createStyleSheet(src);
    }
    else {
        $("head").append($("<link rel='stylesheet' href='"+src+" />"));
    }
};</code>

Simply invoke this function within your $(document).ready() or window.onload function to achieve deferred loading for large CSS files.

Another alternative is to disable JavaScript in your browser and observe the resulting behavior. By doing so, you can verify that the CSS is loaded asynchronously, enhancing the overall website performance.

Remember, conducting a quick Google search can often provide valuable insights into programming challenges. For instance, the query "post load css" yields helpful results such as the one mentioned in the response.

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