:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #6b7280;
  --border: #e5e7eb;
  --new: #1d4ed8;
  --influential: #d97706;
  --linked: #059669;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.5;
}

header {
  text-align: center;
  padding: 2.5rem 1rem 1rem;
}

header h1 {
  margin: 0;
  font-size: 2rem;
  letter-spacing: -0.02em;
}

.subtitle {
  color: var(--muted);
  margin: 0.25rem 0 0;
}

.cards {
  display: flex;
  gap: 1.25rem;
  max-width: 1100px;
  margin: 2rem auto;
  padding: 0 1rem;
  flex-wrap: wrap;
}

.card {
  flex: 1 1 30%;
  min-width: 280px;
  border: 1px solid var(--border);
  border-top: 4px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem;
  background: #fff;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
  display: flex;
  flex-direction: column;
}

.card-new { border-top-color: var(--new); }
.card-influential { border-top-color: var(--influential); }
.card-linked { border-top-color: var(--linked); }

.badge {
  align-self: flex-start;
  color: #fff;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
}

.card-title {
  font-size: 1.15rem;
  margin: 0.75rem 0 0.25rem;
  line-height: 1.3;
}

.meta {
  color: var(--muted);
  font-size: 0.85rem;
  margin: 0 0 0.75rem;
}

.abstract {
  font-size: 0.92rem;
  color: #374151;
  flex: 1;
}

.read-link {
  margin-top: 1rem;
  color: var(--new);
  font-weight: 600;
  text-decoration: none;
  font-size: 0.9rem;
}

.read-link:hover {
  text-decoration: underline;
}

footer {
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
  padding: 2rem 1rem 3rem;
}

@media (max-width: 800px) {
  .cards {
    flex-direction: column;
  }
  .card {
    flex: 1 1 auto;
  }
}