/* GLOBAL FONT */
body {
  font-family: 'Inter', sans-serif;
  color: #374151; /* gray-700 */
  background-color: #F3F4F6; /* gray-100 */
  margin: 0;
  padding: 0;
}

/* HEADINGS */
h1, h2, h3, h4 {
  color: #111827; /* gray-900 */
  font-weight: 700;
}

/* LINKS */
a {
  transition: color 0.2s ease, background-color 0.2s ease;
}

/* BRAND COLORS */
:root {
  --primary: #2563EB; /* blue-600 */
  --primary-light: #3B82F6; /* blue-500 */
  --gray-900: #111827;
  --gray-700: #374151;
  --gray-600: #4B5563;
  --gray-100: #F3F4F6;
  --white: #FFFFFF;

  /* Optional topic accents */
  --algebra: #F59E0B;
  --geometry: #10B981;
  --number: #F43F5E;
  --functions: #6366F1;
}