JS + CSS fade effect

blacklight.html

<style>
    body {
        opacity:0; /* invisible at first */
        transition:opacity 1s; /* transition opacity for 1 second */
    }
</style>

<script>
    document.addEventListener("DOMContentLoaded",function(){ // equivalent to jQuery ready()
        document.body.style.opacity = "1"; // set body's opacity to 1
    })
    /* this method is much better than using jQuery since you don't have to load a huge library
     * to do a simple effect like a fade
     * pls use it */
</script>