:root {
  --bg: #f5f7fb;
  --card: #fff;
  --text: #0f172a;
  --muted: #64748b;
  --border: #e2e8f0;
  --primary: #2563eb;
  --primary-2: #1d4ed8;
  --success: #16a34a;
  --danger: #dc2626;
  --warning: #f59e0b;
  --sidebar: #0b1220;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(15,23,42,.06), 0 4px 12px rgba(15,23,42,.04);
}
[hidden] { display: none !important; }
body.dark {
  --bg: #0b1220; --card: #131c2e; --text: #e2e8f0; --muted: #94a3b8;
  --border: #1e293b;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: 'Inter', system-ui, sans-serif; background: var(--bg); color: var(--text); font-size: 14px; transition: .15s; }
a { cursor: pointer; }

/* Loader */
.loader { position: fixed; inset: 0; background: rgba(15,23,42,.35); display: none; z-index: 9999; align-items: center; justify-content: center; }
.loader.active { display: flex; }
.spinner { width: 36px; height: 36px; border: 3px solid rgba(255,255,255,.4); border-top-color: #fff; border-radius: 50%; animation: spin .8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* Login */
.login { height: 100vh; display: flex; align-items: center; justify-content: center; background: linear-gradient(135deg, #0b1220, #1e3a8a); }
.login form { background: var(--card); padding: 40px 32px; border-radius: var(--radius); box-shadow: 0 20px 60px rgba(0,0,0,.3); width: 340px; text-align: center; }
.login h1 { color: var(--primary); margin-bottom: 24px; }
.login input { width: 100%; padding: 12px; margin: 6px 0; border: 1px solid var(--border); border-radius: 8px; background: var(--bg); color: var(--text); font-size: 14px; }
.login .btn-primary { width: 100%; padding: 12px; margin-top: 10px; background: var(--primary); color: #fff; border: none; border-radius: 8px; font-weight: 600; cursor: pointer; }
.error { color: var(--danger); font-size: 13px; margin-top: 8px; }

/* App shell */
.app { display: flex; height: 100vh; }
.sidebar { width: 220px; background: var(--sidebar); color: #cbd5e1; display: flex; flex-direction: column; }
.brand { padding: 20px; color: #fff; font-weight: 700; font-size: 18px; letter-spacing: 1px; border-bottom: 1px solid rgba(255,255,255,.08); }
.brand span { color: var(--primary); }
#nav { flex: 1; padding: 12px 0; overflow-y: auto; }
#nav a { display: flex; align-items: center; gap: 10px; padding: 10px 20px; font-size: 13.5px; color: #cbd5e1; border-left: 3px solid transparent; }
#nav a:hover { background: rgba(255,255,255,.05); color: #fff; }
#nav a.active { background: rgba(37,99,235,.15); border-left-color: var(--primary); color: #fff; }
#nav a span { font-size: 15px; width: 20px; }
.user { padding: 14px 20px; border-top: 1px solid rgba(255,255,255,.08); font-size: 12px; display: flex; flex-direction: column; gap: 8px; }
.user #me { color: #fff; font-weight: 600; }
.user button { padding: 6px 10px; background: rgba(255,255,255,.08); color: #cbd5e1; border: none; border-radius: 6px; cursor: pointer; font-size: 12px; }

/* View */
.view { flex: 1; overflow-y: auto; padding: 24px; }
.view h2 { font-size: 22px; margin-bottom: 20px; font-weight: 700; }

/* Cards */
.card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); margin-bottom: 20px; }
.card h3 { font-size: 15px; margin-bottom: 14px; font-weight: 600; }

/* KPI grid */
.kpis { display: grid; grid-template-columns: repeat(auto-fit,minmax(200px,1fr)); gap: 16px; margin-bottom: 24px; }
.kpi { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px; box-shadow: var(--shadow); }
.kpi .label { font-size: 11.5px; color: var(--muted); text-transform: uppercase; letter-spacing: .05em; font-weight: 600; }
.kpi .value { font-size: 24px; font-weight: 700; margin-top: 6px; }
.kpi .sub { font-size: 12px; color: var(--muted); margin-top: 4px; }
.kpi.alert { border-left: 4px solid var(--danger); }
.kpi.good { border-left: 4px solid var(--success); }

/* Grid */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.grid-3 { display: grid; grid-template-columns: repeat(3,1fr); gap: 20px; }
@media (max-width: 900px) { .grid-2,.grid-3 { grid-template-columns: 1fr; } .sidebar { width: 68px; } #nav a { padding: 12px; justify-content: center; } #nav a:not(.active) { color: transparent; font-size: 0; } #nav a span { font-size: 16px; } .brand, .user #me { display: none; } }

/* Table */
table { width: 100%; border-collapse: collapse; font-size: 13.5px; }
th { text-align: left; padding: 10px 12px; background: var(--bg); color: var(--muted); font-size: 11.5px; text-transform: uppercase; letter-spacing: .05em; font-weight: 600; border-bottom: 1px solid var(--border); }
td { padding: 11px 12px; border-bottom: 1px solid var(--border); }
tr:hover td { background: rgba(37,99,235,.03); }
tr:last-child td { border-bottom: none; }

/* Buttons */
button, .btn { font-family: inherit; font-size: 13px; padding: 8px 14px; border: 1px solid var(--border); background: var(--card); color: var(--text); border-radius: 8px; cursor: pointer; font-weight: 500; transition: .15s; }
button:hover { background: var(--bg); }
.btn-primary { background: var(--primary); color: #fff; border-color: var(--primary); }
.btn-primary:hover { background: var(--primary-2); }
.btn-danger { background: var(--danger); color: #fff; border-color: var(--danger); }
.btn-sm { padding: 4px 10px; font-size: 12px; }

/* Forms */
input, select, textarea { width: 100%; padding: 9px 12px; font-size: 13.5px; border: 1px solid var(--border); border-radius: 8px; background: var(--card); color: var(--text); margin: 4px 0 12px; font-family: inherit; }
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--primary); }
label { display: block; font-size: 11.5px; font-weight: 600; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; margin-top: 6px; }

/* Toolbar */
.toolbar { display: flex; gap: 10px; align-items: center; margin-bottom: 16px; flex-wrap: wrap; }
.toolbar h2 { flex: 1; margin: 0; }
.toolbar input { max-width: 280px; margin: 0; }

/* Pagination */
.pager { display: flex; justify-content: center; align-items: center; gap: 12px; margin-top: 16px; font-size: 12px; }
.pager button { font-size: 12px; }
.pager span { color: var(--muted); }

/* Modal */
.modal { position: fixed; inset: 0; background: rgba(15,23,42,.55); display: none; align-items: center; justify-content: center; z-index: 1000; padding: 20px; }
.modal.active { display: flex; }
.modal-body { background: var(--card); border-radius: var(--radius); padding: 24px; width: 100%; max-width: 640px; max-height: 90vh; overflow-y: auto; position: relative; box-shadow: 0 20px 60px rgba(0,0,0,.3); }
.modal-body h2 { margin-bottom: 16px; }
.close { position: absolute; top: 12px; right: 16px; font-size: 22px; cursor: pointer; color: var(--muted); }

/* Toast */
#toast { position: fixed; bottom: 24px; right: 24px; padding: 12px 20px; border-radius: 8px; color: #fff; font-size: 13px; display: none; z-index: 2000; box-shadow: 0 10px 30px rgba(0,0,0,.2); }

/* POS */
.pos { display: grid; grid-template-columns: 1fr 380px; gap: 20px; }
@media (max-width: 1000px) { .pos { grid-template-columns: 1fr; } }
.cart-item { display: flex; justify-content: space-between; align-items: center; padding: 6px 0; border-bottom: 1px solid var(--border); font-size: 13px; }
.imei-results { position: absolute; z-index: 100; background: var(--card); border: 1px solid var(--border); border-radius: 8px; width: 100%; box-shadow: var(--shadow); max-height: 220px; overflow-y: auto; }
.imei-results div { padding: 10px 14px; cursor: pointer; border-bottom: 1px solid var(--border); font-size: 13px; }
.imei-results div:hover { background: var(--primary); color: #fff; }
.pay-line { display: flex; gap: 8px; align-items: center; padding: 10px; border: 1px solid var(--border); border-radius: 8px; margin-bottom: 8px; }
.pay-line select { flex: 1; margin: 0; }
.pay-line input { width: 130px; margin: 0; }