:root{
  --bg:#f4f6f8;
  --card:#ffffff;
  --text:#101418;
  --muted:#647286;
  --line:#d9e0e7;
  --brand:#111214;
  --brand-soft:#1d2025;
  --accent:#00b3ff;
  --success:#18b678;
  --danger:#e15252;
  --warning:#f0aa2f;
}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--text);font-family:Arial,sans-serif}
a{text-decoration:none;color:inherit}
.layout{display:grid;grid-template-columns:250px 1fr;min-height:100vh}
.sidebar{background:linear-gradient(180deg,var(--brand),var(--brand-soft));color:#fff;padding:22px 16px}
.brand{font-size:20px;font-weight:800;margin-bottom:20px}
.logo{max-width:140px;height:auto;display:block;margin-bottom:10px}
.nav{display:flex;flex-direction:column;gap:6px}
.nav a{padding:10px 12px;border-radius:10px;color:#cbd2dc;font-size:14px}
.nav a.active,.nav a:hover{background:#0c0f13;color:#fff}
.content{padding:20px}
.topbar{display:flex;align-items:center;justify-content:space-between;margin-bottom:16px}
.title{font-size:24px;font-weight:800}
.muted{color:var(--muted)}
.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px;margin-bottom:14px}
.grid-4{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}
.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}
.kpi .label{font-size:13px;color:var(--muted)}
.kpi .value{font-size:24px;font-weight:800;margin-top:6px}
.table-wrap{overflow:auto}
table{width:100%;border-collapse:collapse}
th,td{padding:10px;border-bottom:1px solid var(--line);font-size:14px;text-align:left}
th{color:var(--muted);font-weight:600}
.badge{padding:4px 8px;border-radius:999px;font-size:12px;font-weight:700}
.badge.pending{background:#fff5df;color:#9a6500}
.badge.paid{background:#e8faf2;color:#0c7f52}
.badge.sent{background:#ecf6ff;color:#0068a8}
.badge.error{background:#ffe9e9;color:#9f2424}
form .row{margin-bottom:10px}
label{font-size:13px;color:var(--muted);display:block}
input,select,textarea{width:100%;margin-top:6px;padding:9px 11px;border:1px solid var(--line);border-radius:10px;background:#fff;color:var(--text)}
textarea{min-height:130px;resize:vertical}
button,.btn{background:var(--accent);color:#032130;border:0;padding:10px 14px;border-radius:10px;font-weight:700;cursor:pointer}
.btn-dark{background:var(--brand);color:#fff}
.btn-danger{background:var(--danger);color:#fff}
.btn-sm{padding:6px 9px;font-size:12px;border-radius:8px}
.actions{display:flex;gap:6px;align-items:center}
.actions form{margin:0}
.chips{display:flex;gap:6px;flex-wrap:wrap}
.chip{padding:3px 8px;border-radius:999px;background:#eef3f8;color:#40556d;font-size:12px}
.flash{padding:10px 12px;border-radius:10px;margin-bottom:10px;font-size:14px}
.flash.success{background:#e9fff4;color:#0f8f5f;border:1px solid #bdebd8}
.flash.error{background:#fff0f0;color:#a23c3c;border:1px solid #f0c4c4}
.login-wrap{min-height:100vh;display:flex;align-items:center;justify-content:center;background:linear-gradient(130deg,#111214,#20242c)}
.login-card{width:100%;max-width:430px;background:#fff;border-radius:16px;padding:26px}
.login-card h1{margin-top:0}
.preview{border:1px solid var(--line);border-radius:10px;padding:8px;background:#fff;min-height:200px}
@media (max-width: 980px){
  .layout{grid-template-columns:1fr}
  .sidebar{padding:14px}
  .nav{flex-direction:row;overflow:auto}
  .grid-4{grid-template-columns:repeat(2,1fr)}
  .grid-2{grid-template-columns:1fr}
}