Remove dead website

Author: ai

src/nav/nav.pug

@@ -7,7 +7,7 @@ nav.nav
       a.nav_link( href="/docs/" )
         | Docs
     li.nav_item
-      a.nav_link( href="https://www.postcss.parts/" )
+      a.nav_link( href="/docs/postcss-plugins" )
         | Plugins
     li.nav_item
       a.nav_link( href="/api/" )

src/way/way.pug

@@ -10,7 +10,7 @@ nav.way
       a.way_link( href="https://github.com/postcss/postcss#articles" )
         | Learn
     li.way_item
-      a.way_link( href="https://www.postcss.parts/" )
+      a.way_link( href="h/docs/postcss-plugins" )
         | Plugins
     li.way_item
       a.way_link( href="https://opencollective.com/postcss/" )