<svg xmlns="http://www.w3.org/2000/svg">
    <filter id="filter">
        <feTurbulence type="fractalNoise" baseFrequency=".1 .01"/>
        <feColorMatrix values="0 0 0 .11 .69
                               0 0 0 .09 .38
                               0 0 0 .08 .14
                               0 0 0 0 1"/>
    </filter>
    <rect width="100%" height="100%" filter="url(#filter)"/>
</svg>

/* Add the seed attribute and set it to a random integer in <feTurbulence> to create your own variant! */
/* Minified (256 bytes):
<svg xmlns="http://www.w3.org/2000/svg"><filter id="a"><feTurbulence type="fractalNoise" baseFrequency=".1 .01"/><feColorMatrix values="0 0 0 .11 .69 0 0 0 .09 .38 0 0 0 .08 .14 0 0 0 0 1"/></filter><rect width="100%" height="100%" filter="url(#a)"/></svg>
*/

External CSS

  1. https://codepen.io/finnhvman/pen/ExgLjmg.css

External JavaScript

  1. https://codepen.io/finnhvman/pen/ExgLjmg.js