Two errors: bg-background class not found and border-border class not found. The @apply directives in globals.css reference Tailwind utility classes that need background and border colors defined in tailwind.config.ts. Let me check both files:

The tailwind.config.ts and globals.css look correct -- background color IS defined in the config and CSS variables are set. The issue is that @apply bg-background in globals.css is failing because Tailwind v3 sometimes can't resolve @apply for custom theme colors inside @layer base when they reference CSS variables. The fix is to use raw CSS instead of @apply:

Replaced @apply bg-background text-foreground with direct CSS properties (background-color and color using the same HSL variables). Tailwind v3 has a known issue where @apply can't resolve custom theme colors defined via CSS variables inside @layer base blocks -- using the raw CSS equivalent avoids this entirely while producing identical output.

v16 was created by restoring v9