* { box-sizing: border-box; }
body { font-family: Arial, sans-serif; margin: 0; background: #f4f6f8; color: #222; }
.nav { display: flex; gap: 16px; align-items: center; background: #1f2937; color: #fff; padding: 12px 20px; }
.nav a { color: #cbd5e1; text-decoration: none; }
.nav a:hover { color: #fff; }
.spacer { flex: 1; }
.muted { color: #94a3b8; font-size: 14px; }
.container { max-width: 960px; margin: 24px auto; padding: 0 16px; }
.card { background: #fff; border-radius: 8px; padding: 20px; box-shadow: 0 1px 3px rgba(0,0,0,.1); margin-bottom: 16px; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; }
.stat { font-size: 32px; font-weight: bold; }
table { width: 100%; border-collapse: collapse; background: #fff; }
th, td { text-align: left; padding: 10px; border-bottom: 1px solid #e5e7eb; }
th { background: #f9fafb; }
label { display: block; margin: 12px 0 4px; font-weight: bold; }
input[type=text], input[type=email], input[type=password], input[type=number], textarea {
  width: 100%; padding: 10px; border: 1px solid #cbd5e1; border-radius: 6px; font-size: 15px;
}
textarea { min-height: 100px; }
.btn { display: inline-block; padding: 9px 16px; background: #2563eb; color: #fff; border: 0; border-radius: 6px; cursor: pointer; text-decoration: none; font-size: 14px; }
.btn:hover { background: #1d4ed8; }
.btn-danger { background: #dc2626; }
.btn-danger:hover { background: #b91c1c; }
.btn-gray { background: #6b7280; }
.error { background: #fee2e2; color: #991b1b; padding: 10px; border-radius: 6px; margin-bottom: 12px; }
.success { background: #dcfce7; color: #166534; padding: 10px; border-radius: 6px; margin-bottom: 12px; }
.login-box { max-width: 380px; margin: 80px auto; }
.inline { display: inline; }