body { background:#f4f7fb; color:#172033; font-family:Arial; margin:0; padding:0; }
header { background:#fff; border-bottom:1px solid #dce3ef; padding:25px; text-align:center; font-size:25px; font-weight:bold; color:#183b8f; }
.box { box-sizing:border-box; background:#fff; border:1px solid #dce3ef; padding:25px; margin:25px auto; border-radius:12px; width:80%; box-shadow:0 8px 24px rgba(37,55,90,.10); }
.btn { background:#3157c8; padding:12px 25px; color:white; text-decoration:none; border-radius:8px; display:inline-block; margin-top:10px; }
.btn:hover, button:hover { background:#2446aa; }
#game { background:#eef4ff; border:1px solid #cdd9ee; padding:20px; border-radius:15px; max-width:500px; margin:auto; text-align:center; }
input { padding:10px; border-radius:8px; border:1px solid #aebbd0; width:80%; margin-top:10px; }
button { padding:10px 20px; background:#3157c8; color:white; border:none; border-radius:8px; cursor:pointer; }
#msg { margin-top:15px; min-height:40px; font-weight:700; }
footer { text-align:center; padding:20px; color:#5f6b7a; margin-top:40px; }
@media(max-width:700px){.box{width:92%;padding:18px}header{font-size:20px}}