body {
  font-family: Arial, sans-serif;
  background-color: #f8f8f8;
  margin: 0;
  padding: 0;
  text-align: center;
}
.container {
  margin-top: 50px;
}
.btn {
  display: inline-block;
  padding: 10px 20px;
  background-color: #4caf50;
  color: white;
  text-decoration: none;
  border-radius: 5px;
}
.info, .rewards {
  margin-top: 20px;
}
ul {
  list-style-type: none;
  padding: 0;
}
li {
  padding: 5px 0;
}

table.leaderboard {
  width: 90%;
  margin: 20px auto;
  border-collapse: collapse;
}
table.leaderboard th, table.leaderboard td {
  border: 1px solid #ddd;
  padding: 8px;
}
table.leaderboard th {
  background-color: #4caf50;
  color: white;
}