body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  line-height: 1.6;
  background: #f9f9f9;
  color: #222;
}

header {
  background: #cc0000;
  color: #fff;
  padding: 20px;
  text-align: center;
}

main {
  padding: 20px;
}

ul {
  list-style: none;
  padding: 0;
}

li::before {
  content: "✔️ ";
}

footer {
  background: #333;
  color: #fff;
  padding: 10px;
  text-align: center;
}

/* Lepsze zachowanie obrazków na telefonach */
img {
  max-width: 100%;
  height: auto;
}

header img {
  height: 60px;
  width: auto;
}

@media (max-width: 600px) {
  header div {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  header img {
    margin-bottom: 10px;
  }
}