:root{
  --bg:#0f172a; --card:#111827; --text:#e5e7eb; --muted:#94a3b8; --accent:#22c55e;
}
*{box-sizing:border-box}
body{margin:0; font:16px/1.6 system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif; background:var(--bg); color:var(--text)}
.header{padding:22px; background:#0b1324; border-bottom:1px solid #1f2433}
.wrap{max-width:900px; margin:0 auto; padding:22px}
nav a{color:var(--muted); text-decoration:none; margin-right:14px; padding:8px 10px; border-radius:10px}
nav a:hover{background:#0b1220; color:#cbd5e1}
nav a.active{background:#0b1b34; color:var(--accent); border:1px solid #1f2f44}
h1,h2,h3{margin:0 0 12px}
.card{background:linear-gradient(180deg,#0b1020,var(--card)); border:1px solid #1f2937; border-radius:16px; padding:18px; box-shadow:0 8px 24px rgba(0,0,0,.25); margin:18px 0}
.btn{display:inline-block; padding:10px 14px; border:1px solid #1f2f44; border-radius:12px; color:#e5e7eb; text-decoration:none}
.btn:hover{background:#0b1220}
footer{color:var(--muted); padding:30px 22px; text-align:center; border-top:1px solid #1f2433}
ul{padding-left:20px}
code{background:#0b1220; padding:.15em .35em; border-radius:6px; border:1px solid #223043}
img {
  max-width: 100%;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.25);
}