Four Stat Cards in Two Rows

This component uses Tailwind's grid system to create a responsive layout with four stat cards in two rows. The outer div sets a dark gray background color. The inner div centers the content and sets the max width. The grid div creates two rows using `grid-cols-2` on small screens and four columns using `grid-cols-4` on large screens. Each stat card div is styled with padding, background color, text, and flex layout. This creates a flexible, responsive stats display.