/* --- CSS Reset & Base Styles --- */
:root {
  --primary-color: #0056b3;
  --primary-hover: #004494;
  --text-main: #333333;
  --text-muted: #666666;
  --bg-color: #f0f2f5;
  --card-bg: #ffffff;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  /* System font stack for zero-latency loading and perfect legibility */
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial,
    sans-serif;
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.6;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  padding: 2rem 1rem;
  align-items: center;
}

/* --- Typography & Header --- */
.site-header {
  text-align: center;
  margin-bottom: 3rem;
  max-width: 800px;
}

.site-header h1 {
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  margin-bottom: 0.5rem;
  color: var(--text-main);
  letter-spacing: -0.5px;
}

.site-header p {
  font-size: 1.1rem;
  color: var(--text-muted);
}

/* --- Layout Grid --- */
.grid-container {
  display: grid;
  /* Automatically handles mobile vs desktop layout */
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  max-width: 1000px;
  width: 100%;
  list-style: none; /* Removes bullet points from ul */
}

/* --- Cards --- */
.card {
  background: var(--card-bg);
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
  border-top: 4px solid var(--primary-color);
  display: flex;
  flex-direction: column;
  transition:
    transform 0.2s ease,
    box-shadow 0.2s ease;
}

/* Hover effects for mouse users */
.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 15px rgba(0, 0, 0, 0.1);
}

.card h2 {
  font-size: 1.3rem;
  margin-bottom: 0.75rem;
}

.card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
  flex-grow: 1; /* Pushes the button to the bottom */
}

/* --- Buttons --- */
.card a {
  display: inline-block;
  background-color: var(--primary-color);
  color: #ffffff;
  text-decoration: none;
  padding: 0.75rem 1.25rem;
  border-radius: 4px;
  font-weight: 600;
  text-align: center;
  transition: background-color 0.2s ease;
}

.card a:hover {
  background-color: var(--primary-hover);
}

/* A11y: Keyboard Focus Outline */
.card a:focus-visible {
  outline: 3px solid #ffaa00;
  outline-offset: 2px;
}

/* --- Footer --- */
.site-footer {
  margin-top: auto; /* Pushes footer to the bottom of the screen */
  padding-top: 3rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
}