:root {
    --primary: #1b6e3c;
    --primary-dark: #124f2a;
    --accent: #e8a33d;
    --danger: #c0392b;
    --bg: #f4f6f5;
    --card: #ffffff;
    --border: #dfe4e1;
    --text: #22302a;
    --text-muted: #6b7a72;
    --radius: 10px;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: 'Segoe UI', Roboto, Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
}

/* ---------- Top bar ---------- */
.topbar {
    background: var(--primary);
    color: #fff;
    padding: 10px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.topbar h1 { font-size: 18px; margin: 0; }
.topbar nav a {
    color: #fff;
    text-decoration: none;
    margin-left: 18px;
    font-size: 14px;
    opacity: 0.9;
}
.topbar nav a:hover { opacity: 1; text-decoration: underline; }
.topbar .user-badge { font-size: 13px; opacity: 0.85; }

/* ---------- Login ---------- */
.login-body {
    display: flex; align-items: center; justify-content: center;
    height: 100vh; background: linear-gradient(135deg, var(--primary), var(--primary-dark));
}
.login-box {
    background: #fff; padding: 36px 32px; border-radius: var(--radius);
    width: 320px; box-shadow: 0 10px 30px rgba(0,0,0,0.25);
}
.login-box h1 { text-align: center; font-size: 20px; margin-bottom: 20px; color: var(--primary-dark); }
.login-box label { display: block; font-size: 13px; margin: 10px 0 4px; color: var(--text-muted); }
.login-box input {
    width: 100%; padding: 10px; border: 1px solid var(--border); border-radius: 6px; font-size: 14px;
}
.login-box button {
    width: 100%; margin-top: 18px; padding: 11px; background: var(--primary); color: #fff;
    border: none; border-radius: 6px; font-size: 15px; cursor: pointer;
}
.login-box button:hover { background: var(--primary-dark); }
.login-box .hint { font-size: 12px; color: var(--text-muted); text-align: center; margin-top: 14px; }
.alert-error {
    background: #fdecea; color: var(--danger); padding: 8px 10px; border-radius: 6px; font-size: 13px; margin-bottom: 8px;
}

/* ---------- Layout ---------- */
.container { padding: 16px 20px; max-width: 1400px; margin: 0 auto; }
.card {
    background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
    padding: 16px; margin-bottom: 16px;
}

/* ---------- POS screen ---------- */
.pos-grid {
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: 16px;
    align-items: start;
}
.scan-row { display: flex; gap: 10px; margin-bottom: 12px; }
.scan-row input {
    flex: 1; padding: 14px; font-size: 18px; border: 2px solid var(--primary); border-radius: 8px;
}
.scan-row button {
    padding: 0 18px; background: var(--primary); color: #fff; border: none; border-radius: 8px; cursor: pointer; font-size: 14px;
}
#scale-status { font-size: 12px; margin-top: 4px; color: var(--text-muted); }
#scale-status.connected { color: var(--primary); font-weight: 600; }

table.cart-table { width: 100%; border-collapse: collapse; font-size: 14px; }
table.cart-table th, table.cart-table td {
    padding: 8px 6px; border-bottom: 1px solid var(--border); text-align: left;
}
table.cart-table th { color: var(--text-muted); font-weight: 600; font-size: 12px; text-transform: uppercase; }
table.cart-table td.num { text-align: right; }
.remove-btn { background: none; border: none; color: var(--danger); cursor: pointer; font-size: 16px; }

.totals-box { font-size: 14px; }
.totals-box .row { display: flex; justify-content: space-between; padding: 6px 0; }
.totals-box .row.grand { font-size: 22px; font-weight: 700; border-top: 2px solid var(--border); margin-top: 8px; padding-top: 10px; color: var(--primary-dark); }

.payment-tabs { display: flex; gap: 8px; margin: 12px 0; }
.payment-tabs button {
    flex: 1; padding: 10px; border: 1px solid var(--border); background: #fff; border-radius: 8px; cursor: pointer; font-size: 14px;
}
.payment-tabs button.active { background: var(--primary); color: #fff; border-color: var(--primary); }

.field { margin-bottom: 10px; }
.field label { display: block; font-size: 12px; color: var(--text-muted); margin-bottom: 4px; }
.field input, .field select {
    width: 100%; padding: 9px; border: 1px solid var(--border); border-radius: 6px; font-size: 14px;
}

.btn-checkout {
    width: 100%; padding: 14px; background: var(--accent); color: #fff; border: none;
    border-radius: 8px; font-size: 17px; font-weight: 700; cursor: pointer; margin-top: 10px;
}
.btn-checkout:hover { filter: brightness(0.95); }
.btn-checkout:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-secondary {
    padding: 9px 14px; background: #eef1ef; border: 1px solid var(--border); border-radius: 6px; cursor: pointer; font-size: 13px;
}

/* ---------- Admin tables ---------- */
table.admin-table { width: 100%; border-collapse: collapse; font-size: 14px; background: #fff; }
table.admin-table th, table.admin-table td { padding: 10px 8px; border-bottom: 1px solid var(--border); text-align: left; }
table.admin-table th { background: #f0f3f1; font-size: 12px; text-transform: uppercase; color: var(--text-muted); }
.low-stock { color: var(--danger); font-weight: 700; }
.badge { padding: 2px 8px; border-radius: 20px; font-size: 11px; background: #e8f3ec; color: var(--primary-dark); }

.toolbar { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; gap: 10px; }
.toolbar input[type=text] { padding: 9px; border: 1px solid var(--border); border-radius: 6px; width: 260px; }
.btn-primary { background: var(--primary); color: #fff; border: none; padding: 9px 16px; border-radius: 6px; cursor: pointer; }

/* Modal */
.modal-overlay {
    position: fixed; inset: 0; background: rgba(0,0,0,0.4); display: none;
    align-items: center; justify-content: center; z-index: 100;
}
.modal-overlay.open { display: flex; }
.modal-box { background: #fff; border-radius: var(--radius); padding: 20px; width: 420px; max-height: 90vh; overflow-y: auto; }
.modal-box h2 { margin-top: 0; font-size: 18px; }
.modal-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 16px; }

/* ---------- Print receipt ---------- */
#receipt { display: none; }
@media print {
    body * { visibility: hidden; }
    #receipt, #receipt * { visibility: visible; }
    #receipt { display: block; position: absolute; top: 0; left: 0; width: 280px; font-family: monospace; font-size: 12px; }
    #receipt .center { text-align: center; }
    #receipt table { width: 100%; border-collapse: collapse; }
    #receipt hr { border: none; border-top: 1px dashed #000; }
}