:root{
  --header-bg:#0b1220;
  --footer-bg:#0f172a;
  --card-bg:#111827;
  --panel-bg:#0b1220;
  --accent:#38bdf8;
  --muted:#9ca3af;
  --success:#34d399;
  --danger:#f87171;
  --gold:#fbbf24;
}

/* Basic layout */
*{box-sizing:border-box}
html,body{height:100%; margin:0}
body{
  font-family: "Segoe UI", Tahoma, sans-serif;
  display:flex; flex-direction:column;
  background:linear-gradient(135deg,#07101a,#0d1622);
  color:#e6edf3;
  min-height:100vh;
}

/* Header */
header{
  padding:18px 20px;
  text-align:center;
  background:var(--header-bg);
  border-bottom:1px solid rgba(255,255,255,0.04);
}
header h1{margin:0; color:var(--accent); font-size:26px}
.subtitle{margin:6px 0 0; font-size:14px; color:#cdd6e0}

/* Play area */
.play-area{display:flex; justify-content:center; margin:18px 0}
.play-btn{
  padding:12px 22px; border-radius:12px; border:none;
  background:#22c55e; color:#fff; font-weight:700; cursor:pointer;
  transition: transform .08s, box-shadow .12s;
}
.play-btn:hover{transform:translateY(-3px); box-shadow:0 10px 30px rgba(34,197,94,0.12)}

/* Main layout */
main{flex:1; display:flex; gap:20px; padding:18px; align-items:flex-start}
.sidebar{width:220px}
.center{flex:1; max-width:780px}

/* Cards */
.card{background:var(--card-bg); border-radius:12px; padding:14px; box-shadow:0 8px 24px rgba(0,0,0,0.45); margin-bottom:16px}
.card-content.center{display:flex; flex-direction:column;align-items:center; gap:10px}

/* How-to: title centered, content left-aligned */
#how-title { text-align:center; margin:0 0 8px; }
#howto { font-size:14px; color:#e2e8f0; text-align:left; line-height:1.45; background:var(--panel-bg); padding:10px; border-radius:8px; }

/* Game card */
.info-card{display:flex; justify-content:space-between; font-weight:700; margin-bottom:10px}
#timer{color:var(--danger)} #elapsed-used{color:#60a5fa} #score{color:var(--success)}

.code-area{background:var(--panel-bg); padding:14px; border-radius:10px; min-height:120px; font-family: "Courier New", monospace; font-size:14px; color:#e6edf3; overflow-x:auto}
.code-area span{display:block; padding:6px 10px; border-radius:8px; transition: background .12s}
.code-area span:hover{background:rgba(255,255,255,0.03)}
.correct{background:rgba(52,211,153,0.18); animation: glow .6s ease}
.wrong{background:rgba(248,113,113,0.18); animation: shake .45s ease}

.result-text{min-height:28px; text-align:center; margin-top:10px}

/* Controls */
.controls{display:flex; justify-content:center; gap:10px; margin-top:12px}
button{padding:8px 14px; border-radius:8px; border:none; cursor:pointer; font-weight:700}
#next-btn{background:#06b6d4;color:#fff}
#retry-btn{background:#f59e0b;color:#fff}

/* Leaderboard */
.leaderboard{text-align:center; color:var(--gold)}
.leaderboard strong{color:#fff}

/* Footer - single elegant bar, made-with above socials */
footer{
  background:var(--footer-bg); color:var(--muted); padding:14px 18px;
  border-top:1px solid rgba(255,255,255,0.04);
}
.footer-inner{display:flex; flex-direction:column; align-items:center; gap:8px}
.footer-text{margin:0; color:#d1d5db}
.socials a{color:var(--muted); margin:0 8px; font-size:18px; transition:color .12s}
.socials a:hover{color:var(--accent)}

/* Animations */
@keyframes shake{
  0%{transform:translateX(0)}
  25%{transform:translateX(-6px)}
  50%{transform:translateX(6px)}
  75%{transform:translateX(-6px)}
  100%{transform:translateX(0)}
}
@keyframes glow{
  0%{box-shadow:0 0 0 rgba(52,211,153,0)}
  50%{box-shadow:0 0 18px rgba(52,211,153,0.45)}
  100%{box-shadow:0 0 0 rgba(52,211,153,0)}
}

/* Responsive */
@media (max-width:980px){
  main{flex-direction:column; padding:12px}
  .sidebar{width:100%}
  .center{max-width:100%}
}