:root{
  --bg:#ffffff; --fg:#0f1a14;
  --ring:#e2e8f0; --muted:#64748b; --brand:#0f8a5f;
  --card:#f6f8fb; --accent:#0f8a5f; --shadow:0 8px 24px rgba(0,0,0,.06);
}
:root[data-theme="dark"], [data-theme="dark"] {
  --bg:#0b0f14; --fg:#e6edf3; --ring:#1f2937; --muted:#9aa6b2; --brand:#34d399;
  --card:#0f1720; --accent:#22c55e; --shadow:0 8px 24px rgba(0,0,0,.3);
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]) {
    --bg:#0b0f14; --fg:#e6edf3; --ring:#1f2937; --muted:#9aa6b2; --brand:#34d399;
    --card:#0f1720; --accent:#22c55e; --shadow:0 8px 24px rgba(0,0,0,.3);
  }
}
*{box-sizing:border-box}
body{margin:0;font-family:ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto;background:var(--bg);color:var(--fg)}
a{text-decoration:none;color:inherit}
.container{max-width:1150px;margin:0 auto;padding:0 20px}
header{position:sticky;top:0;background:var(--bg);border-bottom:1px solid var(--ring);z-index:10}
.nav{display:flex;justify-content:space-between;align-items:center;height:64px}
.brand{font-weight:800;color:var(--brand)}
.menu a{margin-left:18px;color:var(--fg);opacity:.9}
.theme-toggle{border:1px solid var(--ring);background:var(--card);padding:6px 10px;border-radius:999px;cursor:pointer;box-shadow:var(--shadow);font-weight:600}
.btn{display:inline-block;background:var(--accent);color:#fff;padding:12px 16px;border-radius:999px;box-shadow:var(--shadow);font-weight:600}
.card{padding:16px;border:1px solid var(--ring);border-radius:14px;background:var(--card);box-shadow:var(--shadow)}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:16px}
footer{border-top:1px solid var(--ring);margin-top:28px}
footer .foot{display:flex;justify-content:center;gap:10px;align-items:center;height:70px;opacity:.9}
input, textarea{background:var(--bg);color:var(--fg);border:1px solid var(--ring)}