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

body {
  font-family: "Poppins", sans-serif;
  background: linear-gradient(135deg, #dcf7fb 0%, #e8f7e9 100%);
  min-height: 100vh;
}

main {
  max-width: 1400px;
  margin: 2rem auto;
  padding: 0 2rem;
}

.bagian-pembuka {
  text-align: center;
  padding: 3rem 2rem;
  background: white;
  border-radius: 10px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
  margin-bottom: 2rem;
}

.bagian-pembuka h2 {
  font-size: 2.5rem;
  color: #333;
  margin-bottom: 1rem;
  background: linear-gradient(135deg, #ff5722, #ff9800);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.bagian-pembuka p {
  font-size: 1.1rem;
  color: #666;
  max-width: 600px;
  margin: 0 auto;
}

.wadah-konten {
  display: none;
}

.wadah-konten.aktif {
  display: block;
}

.wadah-catatan {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.pesan-kosong {
  grid-column: 1 / -1;
  text-align: center;
  padding: 3rem;
  background: white;
  border-radius: 10px;
  color: #666;
  font-size: 1.1rem;
}

@media (max-width: 768px) {
  .bagian-pembuka {
    padding: 2rem 1rem;
  }

  .bagian-pembuka h2 {
    font-size: 1.8rem;
  }

  .bagian-pembuka p {
    font-size: 1rem;
  }

  .wadah-catatan {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .wadah-catatan {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  }
}