/* ==========================================
DESIGN TOKENS — Hitech-inspired Navy/White
========================================== */
:root {
    --bg-app: #eef1f6;
    --bg-card: #ffffff;
    --bg-input: #ffffff;
    --bg-hover: #f4f7fb;
    --bg-active: #e8edf5;
    --text-primary: #1a2332;
    --text-secondary: #5a6a7e;
    --text-tertiary: #9aaab8;
    --border-color: #dce3ed;
    --border-focus: #1b4fb8;
    --navy-dark: #112d60;
    --navy-mid: #1b4fb8;
    --navy-light: #2563eb;
    --navy-muted: #3b7dd8;
    --accent: #1b4fb8;
    --accent-hover: #163fa0;
    --accent-light: #dbeafe;
    --accent-subtle: #eff5ff;
    --danger: #dc2626;
    --danger-hover: #b91c1c;
    --success: #16a34a;
    --warning: #d97706;
    --shadow-xs: 0 1px 2px rgba(17,45,96,0.05);
    --shadow-sm: 0 2px 6px rgba(17,45,96,0.07);
    --shadow-md: 0 6px 18px rgba(17,45,96,0.10);
    --shadow-lg: 0 12px 32px rgba(17,45,96,0.13);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --safe-bottom: env(safe-area-inset-bottom, 0px);
    --safe-top: env(safe-area-inset-top, 0px);
}

/* ==========================================
RESET & BASE
========================================== */
* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body {
    margin: 0; padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Inter", Helvetica, Arial, sans-serif;
    background: var(--bg-app);
    color: var(--text-primary);
    font-size: 15px; line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden; min-height: 100vh;
}
button { font-family: inherit; cursor: pointer; border: none; background: none; padding: 0; color: inherit; }
input, textarea { font-family: inherit; font-size: 15px; color: var(--text-primary); }

/* ==========================================
HEADER — Navy bar with white navigation (MOBILE)
========================================== */
.app-header {
    background: var(--navy-dark);
    padding: calc(var(--safe-top) + 10px) 16px 10px;
    border-bottom: none;
    position: sticky; top: 0; z-index: 100;
    box-shadow: 0 2px 12px rgba(17,45,96,0.22);
}
.header-inner { display: flex; align-items: center; gap: 16px; max-width: 960px; margin: 0 auto; }
.app-brand { display: none; color: #ffffff; font-size: 16px; font-weight: 700; letter-spacing: -0.3px; white-space: nowrap; flex-shrink: 0; }
.app-brand span { color: #60a5fa; }

/* ==========================================
SEGMENTED NAVIGATION (MOBILE)
========================================== */
.segmented-nav {
    display: flex; background: rgba(255,255,255,0.10); border-radius: 8px; padding: 3px; gap: 2px;
    max-width: 400px; margin: 0 auto; flex: 1;
}
.segment-btn {
    flex: 1; display: flex; align-items: center; justify-content: center; gap: 6px;
    padding: 8px 12px; border-radius: 6px; font-size: 13px; font-weight: 500;
    color: rgba(255,255,255,0.65); background: transparent; border: none; cursor: pointer;
    transition: all 0.14s ease; user-select: none; -webkit-tap-highlight-color: transparent;
}
.segment-btn svg { flex-shrink: 0; }
.segment-btn span { white-space: nowrap; }
.segment-btn.active { background: #ffffff; color: var(--navy-dark); font-weight: 600; box-shadow: 0 2px 6px rgba(0,0,0,0.15); }
.segment-btn:not(.active):hover { background: rgba(255,255,255,0.15); color: rgba(255,255,255,0.90); }
.segment-btn:active { transform: scale(0.96); opacity: 0.88; }

/* ==========================================
LAYOUT
========================================== */
.app-main { padding: 20px 16px; padding-bottom: 108px; max-width: 960px; margin: 0 auto; }
.page { display: none; animation: fadeIn 0.18s ease; }
.page.active { display: block; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(5px); } to { opacity: 1; transform: translateY(0); } }

/* ==========================================
CARDS
========================================== */
.card { background: var(--bg-card); border-radius: var(--radius-md); padding: 18px; margin-bottom: 14px; box-shadow: var(--shadow-sm); border: 1px solid var(--border-color); }
.card-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 14px; padding-bottom: 12px; border-bottom: 1px solid var(--border-color); }
.card-title { margin: 0; font-size: 14px; font-weight: 600; color: var(--navy-dark); text-transform: uppercase; letter-spacing: 0.5px; }

/* ==========================================
INVOICE HEADER CARD
========================================== */
.invoice-header.card { background: var(--navy-dark); border: none; border-radius: var(--radius-md); padding: 16px 20px; display: flex; justify-content: space-between; align-items: center; box-shadow: var(--shadow-md); position: relative; overflow: hidden; }
.invoice-header.card::before { content: ''; position: absolute; right: -20px; top: -20px; width: 100px; height: 100px; border-radius: 50%; background: rgba(255,255,255,0.05); }
.invoice-header.card::after { content: ''; position: absolute; right: 40px; top: 10px; width: 60px; height: 60px; border-radius: 50%; background: rgba(255,255,255,0.04); }
.invoice-label { font-size: 12px; font-weight: 600; letter-spacing: 1px; text-transform: uppercase; color: rgba(255,255,255,0.55); }
.invoice-number { font-size: 18px; font-weight: 700; font-variant-numeric: tabular-nums; color: #ffffff; letter-spacing: 0.5px; }
.item-count { font-size: 12px; color: var(--text-secondary); font-variant-numeric: tabular-nums; font-weight: 500; }

/* ==========================================
FORMS & INPUTS
========================================== */
.form-group { margin-bottom: 14px; }
.form-group:last-child { margin-bottom: 0; }
label { display: block; font-size: 12px; font-weight: 600; color: var(--text-secondary); margin-bottom: 6px; letter-spacing: 0.3px; text-transform: uppercase; }
.input { width: 100%; padding: 10px 12px; background: var(--bg-input); border: 1px solid var(--border-color); border-radius: var(--radius-sm); outline: none; transition: border-color 0.18s, box-shadow 0.18s; color: var(--text-primary); font-size: 14px; }
.input:focus { border-color: var(--border-focus); box-shadow: 0 0 0 3px rgba(27, 79, 184, 0.10); }
.input::placeholder { color: var(--text-tertiary); }
textarea.input { resize: vertical; min-height: 60px; }

/* ==========================================
BUTTONS
========================================== */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 6px; padding: 10px 18px; border-radius: var(--radius-sm); font-size: 13px; font-weight: 600; transition: all 0.14s ease; user-select: none; letter-spacing: 0.2px; }
.btn:active { transform: scale(0.97); opacity: 0.88; }
.btn-primary { background: var(--navy-dark); color: #ffffff; box-shadow: 0 2px 6px rgba(17,45,96,0.25); }
.btn-primary:hover { background: var(--navy-mid); }
.btn-outline { background: var(--bg-card); color: var(--navy-mid); border: 1.5px solid var(--navy-mid); }
.btn-outline:hover { background: var(--accent-subtle); }
.btn-secondary { background: var(--accent-subtle); color: var(--navy-mid); border: 1.5px dashed var(--navy-muted); font-weight: 500; }
.btn-secondary:hover { background: var(--accent-light); }
.btn-danger { background: var(--danger); color: #ffffff; box-shadow: 0 2px 6px rgba(220,38,38,0.20); }
.btn-danger:hover { background: var(--danger-hover); }
.btn-block { width: 100%; margin-top: 12px; }
.btn-icon { width: 34px; height: 34px; display: flex; align-items: center; justify-content: center; border-radius: var(--radius-sm); color: var(--text-secondary); transition: all 0.12s ease; border: 1px solid transparent; }
.btn-icon:hover { background: var(--bg-hover); border-color: var(--border-color); color: var(--navy-mid); }
.btn-icon:active { background: var(--bg-active); transform: scale(0.92); }
.btn-edit-product { color: var(--navy-mid); }
.btn-delete-product { color: var(--danger); }

/* ==========================================
ITEMS & TOTALS
========================================== */
.item-row { display: grid; grid-template-columns: 1fr 60px 82px 34px; gap: 8px; align-items: center; padding: 10px 0; border-bottom: 1px solid var(--border-color); }
.item-row:last-child { border-bottom: none; }
.item-row .input { padding: 8px 10px; font-size: 13.5px; }
.item-total { font-size: 13px; font-weight: 600; text-align: right; font-variant-numeric: tabular-nums; color: var(--navy-mid); padding-bottom: 6px; }
.totals-card { background: var(--navy-dark); border: none; box-shadow: var(--shadow-md); border-radius: var(--radius-md); }
.total-row { display: flex; justify-content: space-between; padding: 6px 0; font-size: 13.5px; color: rgba(255,255,255,0.60); font-variant-numeric: tabular-nums; }
.total-row.grand-total { font-size: 18px; font-weight: 700; color: #ffffff; border-top: 1px solid rgba(255,255,255,0.15); margin-top: 8px; padding-top: 12px; }

/* ==========================================
SEARCH
========================================== */
.search-container { position: relative; margin-bottom: 12px; }
.search-icon { position: absolute; left: 12px; top: 50%; transform: translateY(-50%); color: var(--text-tertiary); pointer-events: none; }
.search-input { padding-left: 38px; padding-right: 38px; background: var(--bg-card); border-color: var(--border-color); }
.clear-search-btn { position: absolute; right: 8px; top: 50%; transform: translateY(-50%); width: 26px; height: 26px; border-radius: 50%; background: var(--bg-active); display: flex; align-items: center; justify-content: center; color: var(--text-secondary); transition: background 0.12s; }
.clear-search-btn:hover { background: var(--border-color); }
.search-meta { font-size: 12px; color: var(--text-secondary); margin-bottom: 12px; padding: 0 2px; font-variant-numeric: tabular-nums; font-weight: 500; text-transform: uppercase; letter-spacing: 0.3px; }

/* ==========================================
SAVED BILL RECORDS
========================================== */
.record-row { background: var(--bg-card); border-radius: var(--radius-md); padding: 14px 16px; margin-bottom: 8px; display: flex; justify-content: space-between; align-items: center; box-shadow: var(--shadow-xs); border: 1px solid var(--border-color); transition: box-shadow 0.14s ease, border-color 0.14s ease; cursor: pointer; }
.record-row:hover { box-shadow: var(--shadow-sm); border-color: var(--navy-muted); }
.record-row:active { transform: scale(0.99); background: var(--bg-hover); }
.record-main { flex: 1; min-width: 0; }
.record-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 4px; }
.record-inv { font-weight: 700; font-size: 13.5px; font-variant-numeric: tabular-nums; color: var(--navy-mid); background: var(--accent-subtle); padding: 2px 8px; border-radius: 4px; letter-spacing: 0.3px; }
.record-date { font-size: 12px; color: var(--text-tertiary); font-variant-numeric: tabular-nums; }
.record-customer { font-size: 14px; font-weight: 500; margin-bottom: 2px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; color: var(--text-primary); }
.record-items-preview { font-size: 12px; color: var(--text-secondary); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.record-total { font-weight: 700; font-size: 15px; font-variant-numeric: tabular-nums; color: var(--navy-dark); margin-left: 14px; white-space: nowrap; }

/* ==========================================
PRODUCTS LIST
========================================== */
.product-row { background: var(--bg-card); border-radius: var(--radius-md); padding: 14px 16px; margin-bottom: 8px; display: flex; justify-content: space-between; align-items: center; box-shadow: var(--shadow-xs); border: 1px solid var(--border-color); transition: box-shadow 0.14s ease; }
.product-row:hover { box-shadow: var(--shadow-sm); border-color: var(--border-color); }
.product-info { flex: 1; min-width: 0; }
.product-name { font-weight: 600; font-size: 14.5px; margin-bottom: 3px; color: var(--text-primary); }
.product-meta { font-size: 12.5px; color: var(--text-secondary); font-variant-numeric: tabular-nums; }
.product-meta .product-code { display: inline-block; background: var(--accent-subtle); color: var(--navy-mid); padding: 1px 6px; border-radius: 3px; font-size: 11.5px; font-weight: 600; letter-spacing: 0.4px; margin-right: 6px; }
.product-actions { display: flex; gap: 4px; }
.empty-state { text-align: center; padding: 48px 20px; color: var(--text-tertiary); font-size: 14px; }
.empty-state::before { content: ''; display: block; width: 40px; height: 40px; margin: 0 auto 12px; border-radius: 50%; background: var(--bg-active); }

/* ==========================================
ACTION BAR (MOBILE)
========================================== */
.action-bar { position: fixed; bottom: 0; left: 0; right: 0; background: var(--navy-dark); border-top: none; padding: 10px 16px calc(10px + var(--safe-bottom)); display: flex; gap: 8px; z-index: 100; box-shadow: 0 -4px 16px rgba(17,45,96,0.18); }
.action-bar .btn { flex: 1; padding: 11px 0; font-size: 13px; }
.action-bar .btn-primary { flex: 1.6; background: #ffffff; color: var(--navy-dark); box-shadow: none; }
.action-bar .btn-primary:hover { background: #f0f6ff; }
.action-bar .btn-outline { border-color: rgba(255,255,255,0.25); color: rgba(255,255,255,0.85); background: rgba(255,255,255,0.08); }
.action-bar .btn-outline:hover { background: rgba(255,255,255,0.14); border-color: rgba(255,255,255,0.40); }

/* ==========================================
AUTOCOMPLETE
========================================== */
.autocomplete-dropdown { position: absolute; background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius-md); box-shadow: var(--shadow-lg); z-index: 1000; max-height: 240px; overflow-y: auto; overscroll-behavior: contain; }
.ac-item { padding: 10px 14px; cursor: pointer; border-bottom: 1px solid var(--border-color); transition: background 0.1s; }
.ac-item:last-child { border-bottom: none; }
.ac-item:hover, .ac-item.active { background: var(--accent-subtle); }
.ac-name { font-size: 13.5px; font-weight: 600; color: var(--text-primary); }
.ac-meta { font-size: 12px; color: var(--text-secondary); font-variant-numeric: tabular-nums; margin-top: 1px; }

/* ==========================================
MODALS
========================================== */
.modal-overlay { position: fixed; inset: 0; background: rgba(17,45,96,0.30); backdrop-filter: blur(4px); -webkit-backdrop-filter: blur(4px); display: flex; align-items: flex-end; justify-content: center; z-index: 2000; animation: fadeIn 0.18s ease; }
.modal { background: var(--bg-card); width: 100%; max-width: 520px; max-height: 90vh; border-radius: var(--radius-lg) var(--radius-lg) 0 0; display: flex; flex-direction: column; animation: slideUp 0.24s cubic-bezier(0.16, 1, 0.3, 1); overflow: hidden; box-shadow: var(--shadow-lg); }
@keyframes slideUp { from { transform: translateY(100%); } to { transform: translateY(0); } }
.modal-header { display: flex; justify-content: space-between; align-items: center; padding: 16px 18px; border-bottom: 1px solid var(--border-color); background: var(--navy-dark); }
.modal-header h2 { margin: 0; font-size: 15px; font-weight: 700; color: #ffffff; letter-spacing: 0.2px; }
.btn-close-modal { width: 28px; height: 28px; border-radius: 50%; background: rgba(255,255,255,0.12); font-size: 18px; line-height: 1; display: flex; align-items: center; justify-content: center; color: rgba(255,255,255,0.80); transition: background 0.12s; }
.btn-close-modal:hover { background: rgba(255,255,255,0.22); }
.modal-body { padding: 18px; overflow-y: auto; flex: 1; }
.modal-footer { padding: 12px 18px calc(12px + var(--safe-bottom)); border-top: 1px solid var(--border-color); display: flex; gap: 8px; flex-wrap: wrap; background: var(--bg-hover); }
.modal-footer .btn { flex: 1; }

/* ==========================================
ITEMS TABLE (in modal view)
========================================== */
.items-table { width: 100%; border-collapse: collapse; margin: 14px 0; font-size: 13.5px; }
.items-table th, .items-table td { padding: 9px 6px; text-align: left; border-bottom: 1px solid var(--border-color); }
.items-table th { font-weight: 600; color: var(--text-secondary); font-size: 11px; text-transform: uppercase; letter-spacing: 0.5px; background: var(--bg-hover); }
.items-table tr:last-child td { border-bottom: none; }
.items-table .num { text-align: right; font-variant-numeric: tabular-nums; }
.items-table .text-right { text-align: right; }
.items-table tfoot td { font-weight: 700; color: var(--navy-dark); background: var(--accent-subtle); }
.record-details { margin-bottom: 14px; font-size: 13.5px; line-height: 1.6; padding: 12px; background: var(--bg-hover); border-radius: var(--radius-sm); border: 1px solid var(--border-color); }
.record-details .text-secondary { color: var(--text-secondary); font-size: 12px; }
.record-notes { margin-top: 12px; padding: 12px; background: var(--bg-hover); border-radius: var(--radius-sm); font-size: 13px; color: var(--text-secondary); border: 1px solid var(--border-color); }

/* ==========================================
TOASTS
========================================== */
.toast-container { position: fixed; top: calc(var(--safe-top) + 68px); left: 50%; transform: translateX(-50%); z-index: 3000; display: flex; flex-direction: column; gap: 8px; pointer-events: none; width: 90%; max-width: 340px; }
.toast { background: var(--navy-dark); color: #fff; padding: 11px 16px; border-radius: var(--radius-sm); font-size: 13.5px; font-weight: 500; text-align: center; box-shadow: var(--shadow-md); animation: toastIn 0.28s cubic-bezier(0.16, 1, 0.3, 1); pointer-events: auto; }
.toast.success { background: var(--success); }
.toast.error { background: var(--danger); }
@keyframes toastIn { from { opacity: 0; transform: translateY(-16px); } to { opacity: 1; transform: translateY(0); } }

/* ==========================================
UTILITY
========================================== */
.hidden { display: none !important; }

/* ==========================================
DESKTOP COMPONENTS (Base/Hidden on Mobile)
========================================== */
.desktop-sidebar, .desktop-header, .desktop-dashboard { display: none; }
.kpi-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; margin-bottom: 20px; }
.kpi-card { background: var(--bg-card); border-radius: var(--radius-md); padding: 16px; border: 1px solid var(--border-color); box-shadow: var(--shadow-xs); display: flex; align-items: center; gap: 12px; }
.kpi-icon { width: 40px; height: 40px; border-radius: 8px; background: var(--accent-subtle); color: var(--navy-mid); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.kpi-content { flex: 1; min-width: 0; }
.kpi-label { font-size: 11px; font-weight: 600; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 4px; }
.kpi-value { font-size: 20px; font-weight: 700; color: var(--navy-dark); font-variant-numeric: tabular-nums; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.analytics-grid { display: grid; grid-template-columns: 1fr; gap: 16px; margin-bottom: 20px; }
.chart-card { background: var(--bg-card); border-radius: var(--radius-md); padding: 16px; border: 1px solid var(--border-color); box-shadow: var(--shadow-xs); }
.chart-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.chart-header h3 { margin: 0; font-size: 14px; font-weight: 600; color: var(--navy-dark); }
.chart-container { position: relative; height: 250px; width: 100%; }
.range-selector { display: flex; gap: 4px; background: var(--bg-hover); padding: 2px; border-radius: 6px; }
.range-selector button { padding: 4px 8px; font-size: 11px; font-weight: 600; border: none; background: transparent; color: var(--text-secondary); border-radius: 4px; cursor: pointer; }
.range-selector button.active { background: var(--bg-card); color: var(--navy-mid); box-shadow: var(--shadow-xs); }

/* Desktop Recent Bills Table */
.desktop-table-container { background: var(--bg-card); border-radius: var(--radius-md); border: 1px solid var(--border-color); box-shadow: var(--shadow-xs); overflow: hidden; }
.desktop-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.desktop-table th { background: var(--bg-hover); padding: 10px 14px; text-align: left; font-weight: 600; color: var(--text-secondary); font-size: 11px; text-transform: uppercase; letter-spacing: 0.5px; border-bottom: 1px solid var(--border-color); }
.desktop-table td { padding: 12px 14px; border-bottom: 1px solid var(--border-color); color: var(--text-primary); }
.desktop-table tr:last-child td { border-bottom: none; }
.desktop-table tr:hover td { background: var(--bg-hover); }
.table-actions { display: flex; gap: 4px; }
.table-actions .btn-icon { width: 28px; height: 28px; }

/* Print Styles */
@media print {
    body * { visibility: hidden; }
    #thermal-print-area, #thermal-print-area * { visibility: visible; }
    #thermal-print-area { position: absolute; left: 0; top: 0; width: 100%; }
    .app-header, .segmented-nav, .action-bar, .modal-overlay, .toast-container, .autocomplete-dropdown, .desktop-sidebar, .desktop-header { display: none !important; }
}