body{background:#0e0e0e;color:white;font-family:Arial;padding:20px;}
.box{border:1px solid #333;padding:15px;margin-bottom:20px;border-radius:8px;}
button{margin:5px;padding:8px;background:#222;color:white;border:1px solid #555;cursor:pointer;}
button.active{background:#00bcd4;color:black;}