body {
  font-family: Arial, sans-serif;
  margin: 0;
  background: #f4f4f4;
}

header {
  background-color: #111;
  color: white;
  padding: 1em;
  text-align: center;
}

nav ul {
  list-style: none;
  padding: 0;
  display: flex;
  justify-content: center;
  background-color: #222;
  margin: 0;
}

nav ul li {
  margin: 0 15px;
}

nav ul li a {
  color: white;
  text-decoration: none;
  font-weight: bold;
}

main {
  padding: 2em;
  max-width: 900px;
  margin: auto;
  background: white;
}

footer {
  text-align: center;
  padding: 1em;
  background: #111;
  color: white;
}

.card {
  border: 1px solid #ccc;
  border-radius: 8px;
  padding: 1em;
  margin: 1em 0;
  background: #fafafa;
}

img.profile {
  width: 100px;
  border-radius: 50%;
  display: block;
  margin-bottom: 0.5em;
}