body {
  margin:0;
  font-family: system-ui;
  background: url("https://asv-wds.clubdesk.com/clubdesk/fileservlet?type=image&id=1000067&s=djEtz2TZF5qwzhkUOwQ0qr6HwH_egpp7x7C4wMDUwZ6ytK0=&imageFormat=_2048x2048") no-repeat center fixed;
  background-size: 60%;
  background-color:#eef3ee;
}
header {
  background:#0b3d0b;
  color:white;
  padding:12px;
  text-align:center;
}
nav {
  display:flex;
  justify-content:space-around;
  background:#cfe5cf;
  padding:10px;
}
nav a { text-decoration:none; font-weight:bold; color:#003300; }
.card {
  background:white;
  margin:10px;
  padding:15px;
  border-radius:8px;
}