NUXT does not optimize static site - vue.js

Question

I have a project in NUXT js and I want to generate a static website.
It does work, but does not optimize it: does not extract the css in a single file with build.extractCSS for example.
Is it something related to the static mode?
I also try some other optimization but they don't seems to work either.
Here my config:
export default {
// Global page headers: https://go.nuxtjs.dev/config-head
target: process.env.NODE_TARGET === 'static' ? 'static' : 'server',
router: {
base: '/myRoute/',
routeNameSplitter: '/'
},
server: {
host: "localhost" // default: localhost
},
head: {
titleTemplate: 'myProject',
title: 'myProject',
meta: [
{ charset: 'utf-8' },
{ name: 'viewport', content: 'width=device-width, initial-scale=1' },
{ hid: 'description', name: 'description', content: '' },
{ name: 'format-detection', content: 'telephone=no' }
],
link: [
{
hid: 'icon',
rel: 'icon',
type: 'image/png',
href: '/favicon.png'
}
]
},
// Global CSS: https://go.nuxtjs.dev/config-css
css: [
'~/assets/css/custom.css'
],
// Plugins to run before rendering page: https://go.nuxtjs.dev/config-plugins
plugins: [
],
// Auto import components: https://go.nuxtjs.dev/config-components
components: true,
// Modules for dev and build (recommended): https://go.nuxtjs.dev/config-modules
buildModules: [
// https://go.nuxtjs.dev/typescript
'#nuxt/typescript-build',
// https://go.nuxtjs.dev/vuetify
['#nuxtjs/vuetify', { treeShake: true }],
"#nuxtjs/svg",
'vue-social-sharing/nuxt'
],
// Modules: https://go.nuxtjs.dev/config-modules
modules: [
// https://go.nuxtjs.dev/axios
'#nuxtjs/axios',
// https://go.nuxtjs.dev/pwa
'#nuxtjs/pwa',
],
pageTransition: {
name: 'slide-fade',
mode: 'out-in'
},
// Axios module configuration: https://go.nuxtjs.dev/config-axios
axios: {},
env: {
NUXT_ENV_API_HOST: process.env.NUXT_ENV_API_HOST,
},
// PWA module configuration: https://go.nuxtjs.dev/pwa
pwa: {
meta: {
/* meta options */
theme_color: "#27363B"
},
manifest: {
lang: 'en'
}
},
// Vuetify module configuration: https://go.nuxtjs.dev/config-vuetify
vuetify: {
optionsPath: './vuetify.options.js',
customVariables: ['~/assets/variables.scss'],
treeShake: true,
// defaultAssets: false,
},
// Build Configuration: https://go.nuxtjs.dev/config-build
// optimizeCSS: true,
// extractCSS: true,
build: {
analyze: {
analyzerMode: 'static'
},
html: {
minify: {
collapseBooleanAttributes: true,
decodeEntities: true,
minifyCSS: true,
minifyJS: true,
processConditionalComments: true,
removeEmptyAttributes: true,
removeRedundantAttributes: true,
trimCustomFragments: true,
useShortDoctype: true,
minifyURLs: true,
removeComments: true,
removeEmptyElements: true
}
},
optimizeCSS: true,
extractCSS: true,
terser: {
parallel: true,
cache: false,
sourceMap: false,
extractComments: {
filename: 'LICENSES'
},
terserOptions: {
mangle: true,
output: {
comments: /^\**!|#preserve|#license|#cc_on/
}
}
},
babel: {
plugins: [
["#babel/plugin-proposal-private-property-in-object", { "loose": true }]
]
},
extend(config, { isDev, isClient }) {
config.module.rules.push({
test: /\.(obj|mtl|fbx|gltf|glb|hdr|bin)$/,
loader: 'file-loader'
})
},
transpile: [
"three"
]
},
}