static/css/_grain.svg

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<svg
   version="1.1"
   viewBox="0 0 256 256"
   width="256"
   height="256"
   opacity="1"
   id="svgrain"
   xmlns="http://www.w3.org/2000/svg"
   xmlns:svg="http://www.w3.org/2000/svg">
  <defs
     id="defs">
    <filter
       id="grain"
       x="0"
       y="0"
       width="1"
       height="1"
       filterUnits="objectBoundingBox"
       primitiveUnits="userSpaceOnUse"
       color-interpolation-filters="linearRGB">
      <feTurbulence
         type="turbulence"
         baseFrequency="0.7"
         numOctaves="7"
         seed="42"
         stitchTiles="stitch"
         x="-1%"
         y="-1%"
         width="102%"
         height="102%"
         result="turbulence"
         id="feTurbulence2" />
      <feSpecularLighting
         surfaceScale="7"
         specularConstant="3"
         specularExponent="10"
         lighting-color="#ffffff"
         x="-1%"
         y="-1%"
         width="102%"
         height="102%"
         in="turbulence"
         result="specularLighting"
         id="feSpecularLighting">
        <feDistantLight
           azimuth="3"
           elevation="163"
           id="feDistantLight" />
      </feSpecularLighting>
    </filter>
  </defs>
  <rect
     width="320"
     height="320"
     fill="#000000"
     id="blackbody"
     x="-32"
     y="-32"
     opacity="0.03" />
  <rect
     width="320"
     height="320"
     fill="#ffffff"
     filter="url(#grain)"
     id="noise"
     x="-32"
     y="-32"
     opacity="0.03" />
</svg>