Add support for shadow-3xl

app/soapbox/components/ui/banner/banner.tsx

@@ -14,7 +14,7 @@ const Banner: React.FC<IBanner> = ({ theme, children, className }) => {
       data-testid='banner'
       className={classNames('fixed bottom-0 left-0 right-0 py-8 z-50', {
         'backdrop-blur bg-primary-900/80': theme === 'frosted',
-        'bg-white dark:bg-slate-800 text-black dark:text-white shadow-2xl dark:shadow-inset': theme === 'opaque',
+        'bg-white dark:bg-slate-800 text-black dark:text-white shadow-3xl dark:shadow-inset': theme === 'opaque',
       }, className)}
     >
       <div className='max-w-4xl mx-auto px-4'>

tailwind.config.js

@@ -11,6 +11,9 @@ module.exports = {
       xl: '1280px',
     },
     extend: {
+      boxShadow: {
+        '3xl': '0 25px 75px -15px rgba(0, 0, 0, 0.25)',
+      },
       fontSize: {
         base: '0.9375rem',
       },