:root{
  --navy-dark:#0b1a2b;
  --navy:#123a5c;
  --blue:#1f8fef;
  --blue-light:#5fc2ff;
  --orange:#ff8a00;
  --orange-light:#ffb347;
  --gold:#ffd166;
  --gray-bg:#f4f7fb;
  --card-bg:#ffffff;
  --text-dark:#132538;
  --text-muted:#6b7c93;
  --green:#1fa96b;
  --red:#e0483e;
  --amber:#f5a524;
  --radius:14px;
  --shadow:0 6px 20px rgba(11,26,43,0.08);
}

*{box-sizing:border-box;}
html,body{margin:0;padding:0;}
body{
  font-family:"Segoe UI",Roboto,Arial,sans-serif;
  background:var(--gray-bg);
  color:var(--text-dark);
  min-height:100vh;
}
a{color:var(--blue);text-decoration:none;}
a:hover{text-decoration:underline;}

.topbar{
  background:linear-gradient(120deg,var(--navy-dark) 0%,var(--navy) 55%,#0f2a45 100%);
  color:#fff;
  padding:10px 18px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  flex-wrap:wrap;
  gap:10px;
  box-shadow:var(--shadow);
  position:sticky;
  top:0;
  z-index:50;
}
.topbar .brand{
  display:flex;
  align-items:center;
  gap:10px;
  font-weight:700;
  font-size:1.05rem;
}
.topbar .brand img{height:38px;width:auto;display:block;}
.topbar nav{display:flex;gap:6px;flex-wrap:wrap;align-items:center;}
.topbar nav a, .topbar nav button{
  color:#eaf3ff;
  background:rgba(255,255,255,0.06);
  border:1px solid rgba(255,255,255,0.12);
  padding:8px 14px;
  border-radius:10px;
  font-size:0.9rem;
  cursor:pointer;
}
.topbar nav a:hover, .topbar nav button:hover{
  background:linear-gradient(90deg,var(--blue),var(--orange));
  text-decoration:none;
  border-color:transparent;
}
.lang-form{display:flex;gap:4px;}
.lang-form button{
  background:rgba(255,255,255,0.08);
  color:#fff;
  border:1px solid rgba(255,255,255,0.2);
  padding:6px 10px;
  border-radius:8px;
  font-size:0.8rem;
  cursor:pointer;
}
.lang-form button.active{
  background:linear-gradient(90deg,var(--blue),var(--orange));
  border-color:transparent;
  font-weight:700;
}

.container{max-width:1150px;margin:0 auto;padding:20px 16px 60px;}

.page-title{
  display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:10px;
  margin-bottom:18px;
}
.page-title h1{font-size:1.4rem;margin:0;color:var(--navy-dark);}
.page-title .sub{color:var(--text-muted);font-size:0.9rem;}

.btn{
  display:inline-flex;align-items:center;gap:6px;
  padding:10px 18px;border-radius:10px;border:none;
  font-size:0.92rem;font-weight:600;cursor:pointer;
  transition:transform .12s ease, box-shadow .12s ease;
}
.btn:hover{text-decoration:none;transform:translateY(-1px);}
.btn-primary{background:linear-gradient(90deg,var(--blue),var(--orange));color:#fff;box-shadow:0 6px 14px rgba(31,143,239,0.3);}
.btn-outline{background:#fff;color:var(--navy);border:1.5px solid var(--navy);}
.btn-success{background:var(--green);color:#fff;}
.btn-danger{background:var(--red);color:#fff;}
.btn-sm{padding:6px 12px;font-size:0.8rem;border-radius:8px;}
.btn-block{width:100%;justify-content:center;}

.card{
  background:var(--card-bg);
  border-radius:var(--radius);
  box-shadow:var(--shadow);
  padding:20px;
  margin-bottom:18px;
}

.stats-grid{
  display:grid;grid-template-columns:repeat(4,1fr);gap:14px;margin-bottom:20px;
}
.stat-card{
  background:var(--card-bg);border-radius:var(--radius);padding:16px 18px;box-shadow:var(--shadow);
  border-left:5px solid var(--blue);
}
.stat-card.orange{border-left-color:var(--orange);}
.stat-card.green{border-left-color:var(--green);}
.stat-card.red{border-left-color:var(--red);}
.stat-card .label{font-size:0.78rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.03em;}
.stat-card .value{font-size:1.35rem;font-weight:800;color:var(--navy-dark);margin-top:4px;}

.filters{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:16px;}
.filters input, .filters select{
  padding:9px 12px;border-radius:9px;border:1.5px solid #d8e2ee;font-size:0.9rem;background:#fff;
}

table.inv-table{width:100%;border-collapse:collapse;background:#fff;border-radius:var(--radius);overflow:hidden;}
table.inv-table thead th{
  background:var(--navy-dark);color:#fff;padding:12px 14px;text-align:left;font-size:0.82rem;text-transform:uppercase;letter-spacing:.03em;
}
table.inv-table tbody td{padding:12px 14px;border-bottom:1px solid #eef2f7;font-size:0.92rem;}
table.inv-table tbody tr:hover{background:#f7fafd;}
.table-scroll{overflow-x:auto;border-radius:var(--radius);box-shadow:var(--shadow);}

.badge{display:inline-block;padding:4px 12px;border-radius:999px;font-size:0.76rem;font-weight:700;letter-spacing:.02em;}
.badge-unpaid{background:#fdeceb;color:var(--red);}
.badge-paid{background:#e6f7ee;color:var(--green);}
.badge-partial{background:#fff4e0;color:var(--amber);}

.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px;}
.form-group{margin-bottom:12px;display:flex;flex-direction:column;gap:5px;}
.form-group label{font-size:0.85rem;font-weight:600;color:var(--navy);}
.form-control{
  padding:10px 12px;border-radius:9px;border:1.5px solid #d8e2ee;font-size:0.92rem;width:100%;background:#fff;
}
.form-control:focus{outline:none;border-color:var(--blue);box-shadow:0 0 0 3px rgba(31,143,239,0.15);}
.section-heading{
  font-size:0.95rem;font-weight:800;color:var(--navy-dark);
  text-transform:uppercase;letter-spacing:.03em;
  margin:6px 0 12px;padding-bottom:8px;border-bottom:2px solid var(--blue-light);
  display:flex;align-items:center;gap:8px;
}
.section-heading.orange{border-bottom-color:var(--orange-light);}

.two-col{display:grid;grid-template-columns:1fr 1fr;gap:18px;}

.items-table{width:100%;border-collapse:collapse;margin-bottom:10px;}
.items-table th{background:#eef4fb;padding:8px 10px;font-size:0.78rem;text-transform:uppercase;color:var(--navy);text-align:left;}
.items-table td{padding:6px;}
.items-table input{width:100%;}
.items-table .del-col{width:40px;text-align:center;}

.messages{list-style:none;padding:0;margin:0 0 14px;}
.messages li{padding:10px 14px;border-radius:9px;margin-bottom:8px;font-size:0.9rem;}
.messages .success{background:#e6f7ee;color:var(--green);}
.messages .error{background:#fdeceb;color:var(--red);}

/* Invoice detail / printable */
.invoice-sheet{
  background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);
  padding:30px;
}
.invoice-header{
  display:flex;justify-content:space-between;align-items:flex-start;flex-wrap:wrap;gap:16px;
  padding-bottom:18px;border-bottom:3px solid;
  border-image:linear-gradient(90deg,var(--blue),var(--orange)) 1;
  margin-bottom:20px;
}
.invoice-header .brand-block{display:flex;gap:12px;align-items:center;}
.invoice-header .brand-block img{height:60px;width:auto;}
.invoice-header .brand-block .cname{font-size:1.25rem;font-weight:800;color:var(--navy-dark);}
.invoice-header .brand-block .cmeta{font-size:0.82rem;color:var(--text-muted);line-height:1.5;}
.invoice-header .inv-meta{text-align:right;}
.invoice-header .inv-meta .inv-title{
  font-size:1.6rem;font-weight:900;
  background:linear-gradient(90deg,var(--blue),var(--orange));
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.invoice-header .inv-meta .inv-number{font-weight:700;color:var(--navy-dark);}
.invoice-header .inv-meta .inv-dates{font-size:0.85rem;color:var(--text-muted);margin-top:4px;}

.bill-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin-bottom:22px;}
.bill-box{background:#f7fafd;border-radius:10px;padding:14px 16px;border-left:4px solid var(--blue);}
.bill-box.to{border-left-color:var(--orange);}
.bill-box h4{margin:0 0 8px;font-size:0.78rem;text-transform:uppercase;letter-spacing:.04em;color:var(--text-muted);}
.bill-box .name{font-weight:700;font-size:1.02rem;color:var(--navy-dark);margin-bottom:2px;}
.bill-box .line{font-size:0.86rem;color:var(--text-dark);}

.status-row{display:flex;justify-content:space-between;align-items:center;margin-bottom:18px;flex-wrap:wrap;gap:10px;}

table.line-items{width:100%;border-collapse:collapse;margin-bottom:20px;}
table.line-items thead th{background:var(--navy-dark);color:#fff;padding:10px 12px;font-size:0.8rem;text-transform:uppercase;}
table.line-items tbody td{padding:10px 12px;border-bottom:1px solid #eef2f7;font-size:0.92rem;}
table.line-items tfoot td{padding:10px 12px;font-weight:700;}
.text-right{text-align:right;}

.totals-box{margin-left:auto;width:100%;max-width:320px;}
.totals-box .row{display:flex;justify-content:space-between;padding:6px 0;font-size:0.92rem;}
.totals-box .row.grand{font-size:1.15rem;font-weight:800;border-top:2px solid var(--navy-dark);padding-top:10px;color:var(--navy-dark);}
.totals-box .row.paid{color:var(--green);}
.totals-box .row.balance{color:var(--red);font-weight:700;}

.payment-info{background:#fff8ec;border-left:4px solid var(--gold);border-radius:10px;padding:14px 16px;margin-top:10px;}
.payment-info h4{margin:0 0 8px;font-size:0.85rem;color:var(--navy-dark);text-transform:uppercase;letter-spacing:.03em;}
.payment-info .method{margin-bottom:10px;font-size:0.88rem;}
.payment-info .method b{color:var(--navy);}

.action-bar{display:flex;gap:10px;flex-wrap:wrap;margin-top:20px;}

.login-wrap{
  min-height:100vh;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,var(--navy-dark),var(--navy) 60%, #0f2a45);
  padding:20px;
}
.login-card{background:#fff;border-radius:var(--radius);box-shadow:0 20px 50px rgba(0,0,0,0.35);padding:32px;width:100%;max-width:380px;text-align:center;}
.login-card img{height:70px;margin-bottom:12px;}

.empty-state{text-align:center;padding:40px 20px;color:var(--text-muted);}

@media (max-width:900px){
  .stats-grid{grid-template-columns:repeat(2,1fr);}
  .form-grid{grid-template-columns:1fr;}
  .two-col{grid-template-columns:1fr;}
  .bill-grid{grid-template-columns:1fr;}
}
@media (max-width:600px){
  .stats-grid{grid-template-columns:1fr 1fr;}
  .topbar{padding:10px;}
  .topbar .brand span{display:none;}
  .invoice-sheet{padding:16px;}
  .invoice-header{flex-direction:column;}
  .invoice-header .inv-meta{text-align:left;}
  .container{padding:14px 10px 50px;}
  .page-title{flex-direction:column;align-items:flex-start;}
}

@media print{
  .topbar, .action-bar, .filters, .no-print{display:none !important;}
  body{background:#fff;}
  .container{padding:0;max-width:100%;}
  .invoice-sheet{box-shadow:none;padding:0;}
}