:root {
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-card: #161b22;
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --accent: #58a6ff;
  --accent-hover: #79c0ff;
  --border: #30363d;
  --border-hover: #484f58;
  --radius: 12px;
  --max-width: 900px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial,
    sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
}

/* Header */
header {
  padding: 64px 0 56px;
}

header h1 {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 6px;
}

header .tagline {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* Projects Grid */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 12px;
  padding-bottom: 64px;
}

/* Card */
a.card-link {
  display: block;
  text-decoration: none;
  color: inherit;
  border-radius: var(--radius);
}

a.card-link:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: border-color 0.15s ease, background 0.15s ease;
  height: 100%;
}

a.card-link:hover .card {
  border-color: var(--border-hover);
  background: #1c2128;
}

.card h2 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  flex-grow: 1;
  line-height: 1.55;
}

/* Footer */
footer {
  margin-top: auto;
  padding: 24px 0;
}

footer p {
  color: var(--text-secondary);
  font-size: 0.82rem;
}

/* Responsive */
@media (max-width: 600px) {
  header {
    padding: 48px 0 40px;
  }

  header h1 {
    font-size: 1.6rem;
  }

  .projects-grid {
    grid-template-columns: 1fr;
  }
}