:root{
  --accent:#0b6ef6;
  --muted:#6b7280;
  --bg:#f5f7fb;
  --card:#ffffff;
  --max-w:1100px;
}

*{box-sizing:border-box}
body{
  margin:0;
  font-family:Inter,ui-sans-serif,system-ui,Arial,Helvetica,sans-serif;
  background:var(--bg);
  color:#111827;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}

.container{max-width:var(--max-w);margin:0 auto;padding:18px;}

.site-header{background:linear-gradient(90deg,var(--accent),#1572ff);color:white;position:sticky;top:0;z-index:40;}
.header-inner{display:flex;align-items:center;justify-content:space-between;padding:14px 18px;}
.brand{margin:0;font-size:20px}
.main-nav{display:flex;gap:8px}
.nav-btn{background:transparent;border:1px solid rgba(255,255,255,0.2);color:white;padding:8px 10px;border-radius:8px;cursor:pointer}
.nav-btn:hover{background:rgba(255,255,255,0.06)}

main.container{margin-top:20px;}
.page{background:var(--card);padding:20px;border-radius:10px;box-shadow:0 6px 20px rgba(2,6,23,0.06);margin-bottom:18px}

.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;margin-top:12px}
.card{padding:14px;border-radius:8px;background:linear-gradient(180deg,#fff,#fbfdff);border:1px solid #eef3ff}

.form-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:12px;margin-top:12px}
label{display:flex;flex-direction:column;font-weight:600;font-size:14px}
input[type="number"], input[type="text"], textarea{padding:10px;border-radius:8px;border:1px solid #e5e7eb;margin-top:6px}
input[type="checkbox"]{margin-right:8px}

.actions{margin-top:14px;display:flex;gap:10px;align-items:center}
button{background:var(--accent);color:white;border:none;padding:10px 14px;border-radius:8px;cursor:pointer}
button.secondary{background:#fff;border:1px solid var(--accent);color:var(--accent)}
button.link{background:transparent;color:var(--accent);border:0;padding:8px;font-size:14px}
button:disabled{opacity:0.6;cursor:not-allowed}

.result{margin-top:12px;padding:12px;border-radius:8px;background:#eef9ff;border:1px solid #dff1ff}
.hidden{display:none}
.muted{color:var(--muted);margin-bottom:6px;font-size:14px}
.note{margin-top:12px;color:var(--muted);font-size:13px}
.small{font-size:13px}
.site-footer{padding:12px 0;background:transparent;color:var(--muted)}
.site-footer .container{display:flex;justify-content:space-between;align-items:center}

@media (max-width:600px){
  .header-inner{flex-direction:column;gap:10px}
  .main-nav{flex-wrap:wrap;justify-content:center}
}