body {
    font-family: Tahoma, sans-serif;
    text-align: center;
    background-size: 100%;
  background-color: #ff00ff;
}

header { background:#222; color:#fff; padding:10px; text-align:center; }
.container { display:flex; min-height:100vh; }
nav { width:220px; background:#333; color:#fff; padding-top:20px; }
nav a { display:block; padding:12px 20px; color:#fff; text-decoration:none; margin-bottom:5px; }
nav a:hover { background:#ff1138; }
main { flex:1; padding:20px; }
.card { background:#fff; padding:15px; margin-bottom:20px; border-radius:6px; box-shadow:0 2px 5px rgba(0,0,0,0.1); }
button { padding:10px 15px; margin-top:5px; border:none; border-radius:5px; background:#3811ff; color:#fff; cursor:pointer; }
button:hover { background:#ff1138; }