Here is a nifty script that makes your like look more colorful. Chameleon Site changes the color of your site with every key hit or mouse movement. It uses 3 variables to change the color of your buttons, headers, and links. As you can see in the below code, this snippet is designed to take into account mouse movements and key presses but you can add other event listeners too.
Once you add this code to your functions.php, you will have to modify your CSS file to take into account these variables. You can do so with something like this:
h2{color:var(--c1);}
a:hover{color:var(--c2);}
button{background:var(--c3);}
This script doesn’t use any external calls and won’t slow down your website. Probably a nice option for holidays or special occasions.