vercel.json

{
  "routes": [
    { "handle": "filesystem" },
    { "src": "/shimmer/(.*)", "status": 404, "dest": "/shimmer/404.html" },
    { "src": "/next/(.*)", "status": 404, "dest": "/next/404.html" },
    { "src": "/(.*)", "status": 404, "dest": "/404.html" }
  ],
  "outputDirectory": "build",
  "installCommand": "",
  "buildCommand": ""
}