:root {
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --success: #10b981;
    --success-hover: #059669;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --warning: #f59e0b;
    --secondary: #64748b;
    --secondary-hover: #475569;
    
    --sidebar-bg: #0b1628;
    --sidebar-hover: rgba(255,255,255,0.06);
    --sidebar-text: #94a3b8;
    --sidebar-active: #ffffff;
    --sidebar-accent: #3b82f6;
    --sidebar-width: 240px;
    
    --header-bg: #ffffff;
    --header-border: #e2e8f0;
    
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border: #e2e8f0;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    min-height: 100vh;
}

/* Layout */
.app-container { display: flex; height: 100vh; overflow: hidden; }

/* ═══════════════════════════════════════════════════════════
   SIDEBAR — Professional Grouped Navigation
═══════════════════════════════════════════════════════════ */
.sidebar {
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    color: var(--sidebar-text);
    display: flex;
    flex-direction: column;
    z-index: 20;
    border-right: 1px solid rgba(255,255,255,0.06);
    flex-shrink: 0;
}

/* Logo */
.logo-container {
    padding: 22px 20px 20px;
    display: flex;
    align-items: center;
    gap: 12px;
    border-bottom: 1px solid rgba(255,255,255,0.07);
    background: rgba(0,0,0,0.2);
}

.logo-icon-wrap {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, #3b82f6, #1d4ed8);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    flex-shrink: 0;
    box-shadow: 0 4px 12px rgba(59,130,246,0.35);
}

.logo-container h1 { font-size: 20px; font-weight: 700; color: #ffffff; line-height: 1.1; }
.logo-container h1 span { display: block; font-size: 11px; font-weight: 500; color: var(--sidebar-text); margin-top: 4px; text-transform: uppercase; }

/* Nav Menu Container */
.nav-menu {
    padding: 14px 10px 14px;
    display: flex;
    flex-direction: column;
    gap: 2px;
    overflow-y: auto;
    flex: 1;
    scrollbar-width: thin;
    scrollbar-color: rgba(255,255,255,0.1) transparent;
}
.nav-menu::-webkit-scrollbar { width: 4px; }
.nav-menu::-webkit-scrollbar-track { background: transparent; }
.nav-menu::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 4px; }

/* Section Labels */
.nav-section-label {
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.2px;
    color: #475569;
    padding: 6px 12px 4px;
    margin-top: 4px;
    pointer-events: none;
    user-select: none;
}

/* Section Divider */
.nav-divider {
    height: 1px;
    background: rgba(255,255,255,0.06);
    margin: 8px 12px;
}

/* Nav Button */
.nav-btn {
    position: relative;
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 9px 12px 9px 14px;
    border: none;
    background: transparent;
    color: var(--sidebar-text);
    font-size: 13.5px;
    font-weight: 500;
    text-align: left;
    border-radius: 8px;
    cursor: pointer;
    width: 100%;
    transition: background 0.18s ease, color 0.18s ease, padding-left 0.18s ease;
    overflow: hidden;
}

/* Active indicator bar */
.nav-btn::before {
    content: '';
    position: absolute;
    left: 0;
    top: 20%;
    height: 60%;
    width: 3px;
    background: var(--sidebar-accent);
    border-radius: 0 3px 3px 0;
    opacity: 0;
    transition: opacity 0.18s ease;
}

.nav-btn:hover {
    background: var(--sidebar-hover);
    color: #e2e8f0;
}

.nav-btn.active {
    background: rgba(59,130,246,0.15);
    color: var(--sidebar-active);
    font-weight: 600;
}

.nav-btn.active::before {
    opacity: 1;
}

.nav-btn .icon {
    font-style: normal;
    font-size: 16px;
    color: inherit;
    flex-shrink: 0;
    opacity: 0.85;
    transition: opacity 0.18s ease;
}

.nav-btn.active .icon,
.nav-btn:hover .icon {
    opacity: 1;
}


/* Main Content */
.main-content { flex: 1; display: flex; flex-direction: column; overflow-y: auto; }

.top-header { 
    display: flex; justify-content: space-between; align-items: center; 
    padding: 15px 30px; 
    background: var(--header-bg); 
    border-bottom: 1px solid var(--header-border); 
    position: sticky; top: 0; z-index: 10;
}
.top-header h2 { font-size: 20px; font-weight: 600; color: var(--text-main); }

.user-profile {
    display: flex; align-items: center; gap: 10px; background: #ffffff;
    padding: 4px 12px 4px 4px; border-radius: 20px; border: 1px solid var(--border); 
}
.user-profile:hover { border-color: #cbd5e1; background: #f8fafc; }
.user-profile img { width: 32px; height: 32px; border-radius: 50%; border: 1px solid #e2e8f0; }
.user-profile span { font-weight: 600; font-size: 14px; color: var(--text-main); }

/* Tab Content */
.tab-content { padding: 25px 30px 40px; }
.tab-pane { display: none; }
.tab-pane.active { display: block; }

/* Flat Solid Cards */
.card {
    background: var(--card-bg);
    border-radius: 8px; border: 1px solid var(--border);
    margin-bottom: 25px; overflow: hidden;
}

.card-header { padding: 20px 25px; border-bottom: 1px solid var(--border); background: #f8fafc; }
.card-header h3 { font-size: 16px; color: var(--text-main); font-weight: 600; margin-bottom: 4px; }
.card-header p { color: var(--text-muted); font-size: 13px; line-height: 1.4; }

.flex-between { display: flex; justify-content: space-between; align-items: center; }
.card-body { padding: 25px; }

/* Upload Area */
.upload-area {
    border: 2px dashed #cbd5e1; border-radius: 6px; padding: 15px; text-align: center;
    background: #f8fafc; cursor: pointer;
}
.upload-area:hover, .upload-area.dragover { background: #eff6ff; border-color: var(--primary); }
.upload-icon { font-size: 24px; margin-bottom: 4px; display: inline-block; color: var(--primary); }
.upload-area h4 { font-size: 14px; font-weight: 600; margin-bottom: 0; color: var(--text-main); }
.upload-area p { display: none; }

/* Buttons */
.btn {
    padding: 8px 16px; border-radius: 6px; font-weight: 500; font-size: 13px; 
    cursor: pointer; border: none; display: inline-flex; align-items: center; justify-content: center; gap: 6px;
    color: white; outline: none; text-decoration: none;
}
.btn-primary { background: var(--primary); }
.btn-primary:hover { background: var(--primary-hover); }

.btn-secondary { background: var(--secondary); }
.btn-secondary:hover { background: var(--secondary-hover); }

.btn-success { background: var(--success); }
.btn-success:hover { background: var(--success-hover); }

.btn-danger { background: var(--danger); }
.btn-danger:hover { background: var(--danger-hover); }

.btn-sm { padding: 5px 10px; font-size: 12px; border-radius: 4px; }

/* Table Minimalist */
.table-responsive { overflow-x: auto; border: 1px solid var(--border); border-radius: 6px; background: white; margin-top: 10px; }
.data-table { width: 100%; border-collapse: collapse; min-width: 800px; }
.data-table th, .data-table td { padding: 12px 15px; text-align: left; border-bottom: 1px solid var(--border); }
.data-table th { 
    background: #f1f5f9; font-weight: 600; color: #334155; font-size: 13px; 
    position: sticky; top: 0; z-index: 5;
}
.data-table td { font-size: 13px; color: #334155; }
.data-table tbody tr:hover { background: #f8fafc; }
.data-table tbody tr:last-child td { border-bottom: none; }

.badge { 
    background: var(--success); color: white; padding: 4px 10px; border-radius: 12px; font-size: 11px; font-weight: 500; 
}

.placeholder-content { text-align: center; padding: 60px 20px; color: var(--text-muted); font-size: 14px; }

/* Form Controls */
.form-control {
    padding: 8px 12px; border: 1px solid #cbd5e1; border-radius: 6px; font-size: 13px;
    background: #ffffff; color: var(--text-main); outline: none; min-width: 150px;
}
.form-control:focus { border-color: var(--primary); }

/* Modals */
.modal-content {
    background: white; padding: 25px !important; border-radius: 8px !important; 
    border: 1px solid var(--border); box-shadow: 0 4px 20px rgba(0,0,0,0.1) !important;
}

/* Utility */
.print-only { display: none; }
.print-only-inline { display: none; }

/* Print Styles */
@media print {
    body { background: white; margin: 0; padding: 0; }
    
    * { box-shadow: none !important; text-shadow: none !important; transition: none !important; }
    
    .sidebar, .top-header, .no-print, .modal { display: none !important; }
    .card-header .actions, .card-header h3, .card-header p, #totalRows, .upload-area, .btn { display: none !important; }
    
    .app-container, .main-content, .tab-content { display: block !important; padding: 0 !important; margin: 0 !important; height: auto !important; overflow: visible !important; }
    .tab-pane { display: none !important; }
    .tab-pane.active { display: block !important; }
    
    .print-only { display: block !important; }
    .print-only-inline { display: inline !important; }
    th.print-only-cell, td.print-only-cell { display: table-cell !important; }
    
    .card { box-shadow: none !important; border: none !important; background: transparent !important; padding: 0 !important; margin: 0 !important; }
    .card-body { padding: 0 !important; margin: 0 !important; }
    
    .data-table { width: 100% !important; border-collapse: collapse !important; table-layout: auto !important; }
    .data-table th, .data-table td { border: 1px solid #333 !important; padding: 6px !important; font-size: 11px !important; color: #000 !important; background: transparent !important; }
    .data-table th { background: #f5f5f5 !important; -webkit-print-color-adjust: exact; color: #000 !important; font-weight: bold !important; }
    
    .category-block { page-break-inside: avoid; margin-bottom: 25px !important; }
}