docs: fix storybook style (#126)

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@coderabbitai summary

Author: MGREMY

apps/storybook/styles.css

@@ -1,6 +1,8 @@
-@custom-variant dark (&:where([data-mode='dark'] &, .dark &));
+@import 'tailwindcss';
+
+@source "../../../../libs/flowbite-angular";
 
-@import '../../libs/flowbite-angular/styles/flowbite-angular.css';
+@custom-variant dark (&:where([data-mode='dark'] &, .dark &));
 
 @font-face {
   font-family: roboto;