/* === Reset & Base === */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #dbeafe;
    --accent: #059669;
    --accent-light: #d1fae5;
    --danger: #dc2626;
    --danger-light: #fee2e2;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-500: #6b7280;
    --gray-700: #374151;
    --gray-900: #111827;
    --sidebar-width: 250px;
    --topbar-height: 56px;
    --radius: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-lg: 0 4px 6px rgba(0,0,0,0.1), 0 2px 4px rgba(0,0,0,0.06);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 14px;
    line-height: 1.5;
    color: var(--gray-900);
    background: var(--gray-100);
}

a {
    color: var(--primary);
    text-decoration: none;
}

/* === Login Page === */
.login-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(135deg, rgba(15, 15, 20, 0.85) 0%, rgba(30, 25, 10, 0.80) 100%),
                url('https://images.unsplash.com/photo-1610375461246-83df859d849d?auto=format&fit=crop&w=1920&q=80') center/cover no-repeat fixed;
    background-color: #0f0f14;
}

.login-container {
    width: 100%;
    max-width: 420px;
    padding: 20px;
}

.login-card {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 12px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(255, 215, 0, 0.1);
    padding: 44px 36px;
    backdrop-filter: blur(10px);
}

.login-header {
    text-align: center;
    margin-bottom: 32px;
}

.login-header h1 {
    font-size: 24px;
    color: var(--gray-900);
    margin-bottom: 6px;
    letter-spacing: -0.3px;
}

.login-header p {
    color: var(--gray-500);
    font-size: 13px;
}

.login-form .form-group {
    margin-bottom: 20px;
}

.login-form label {
    display: block;
    margin-bottom: 6px;
    font-weight: 500;
    font-size: 13px;
    color: var(--gray-700);
}

.login-form input {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    transition: border-color 0.15s;
}

.login-form input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.login-footer {
    text-align: center;
    margin-top: 24px;
    color: var(--gray-500);
}

/* === Alerts === */
.alert {
    padding: 12px 16px;
    border-radius: 6px;
    margin-bottom: 20px;
    font-size: 13px;
}

.alert-error {
    background: var(--danger-light);
    color: var(--danger);
    border: 1px solid #fca5a5;
}

/* === Buttons === */
.btn {
    display: inline-block;
    padding: 10px 20px;
    border: none;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.15s;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

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

.btn-block {
    width: 100%;
}

.btn-logout {
    background: var(--danger);
    color: #fff;
    padding: 6px 16px;
    border-radius: 6px;
    font-size: 13px;
    transition: background 0.15s;
}

.btn-logout:hover {
    background: #b91c1c;
    color: #fff;
}

/* === Layout === */
.layout {
    display: flex;
    min-height: 100vh;
}

/* === Sidebar === */
.sidebar {
    width: var(--sidebar-width);
    background: var(--gray-900);
    color: #fff;
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    overflow-y: auto;
    z-index: 100;
    transition: transform 0.3s;
}

.sidebar-header {
    padding: 20px 16px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.sidebar-header h2 {
    font-size: 16px;
    font-weight: 600;
}

.sidebar-subtitle {
    font-size: 11px;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.sidebar-nav {
    padding: 12px 0;
}

.nav-section {
    padding: 16px 16px 4px;
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--gray-500);
    font-weight: 600;
}

.nav-item {
    display: flex;
    align-items: center;
    padding: 10px 16px;
    color: var(--gray-300);
    font-size: 13px;
    transition: background 0.15s, color 0.15s;
    gap: 10px;
}

.nav-item:hover {
    background: rgba(255,255,255,0.08);
    color: #fff;
}

.nav-item.active {
    background: var(--primary);
    color: #fff;
    font-weight: 500;
}

.nav-item.disabled {
    opacity: 0.4;
    cursor: not-allowed;
    pointer-events: none;
}

.nav-icon {
    font-size: 8px;
    width: 16px;
    text-align: center;
}

/* === Main Content === */
.main-content {
    margin-left: var(--sidebar-width);
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* === Topbar === */
.topbar {
    height: var(--topbar-height);
    background: #fff;
    border-bottom: 1px solid var(--gray-200);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    position: sticky;
    top: 0;
    z-index: 50;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    color: var(--gray-700);
}

.topbar-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.user-info {
    font-size: 13px;
    color: var(--gray-700);
}

/* === Content Area === */
.content {
    padding: 24px;
    flex: 1;
}

.content h1 {
    font-size: 24px;
    margin-bottom: 4px;
}

.subtitle {
    color: var(--gray-500);
    margin-bottom: 24px;
}

/* === Stats Grid === */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 24px;
}

.stat-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 20px;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--primary);
}

.stat-card.accent {
    border-left-color: var(--accent);
}

.stat-value {
    font-size: 28px;
    font-weight: 700;
    color: var(--gray-900);
    line-height: 1.2;
}

.stat-label {
    font-size: 12px;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-top: 4px;
}

/* === Panels === */
.panel {
    background: #fff;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 24px;
    overflow: hidden;
}

.panel h2 {
    font-size: 16px;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
}

/* === Tables === */
.table-responsive {
    overflow-x: auto;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
}

.data-table th {
    background: var(--gray-50);
    padding: 10px 16px;
    text-align: left;
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--gray-500);
    font-weight: 600;
    border-bottom: 1px solid var(--gray-200);
    white-space: nowrap;
}

.data-table td {
    padding: 10px 16px;
    border-bottom: 1px solid var(--gray-100);
    font-size: 13px;
}

.data-table tbody tr:hover {
    background: var(--gray-50);
}

.text-right {
    text-align: right;
}

.empty-row {
    text-align: center;
    color: var(--gray-500);
    padding: 32px 16px !important;
}

/* === Badge === */
.badge {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 600;
    background: var(--gray-100);
    color: var(--gray-700);
}

/* === Footer === */
.main-footer {
    padding: 16px 24px;
    text-align: center;
    font-size: 12px;
    color: var(--gray-500);
    border-top: 1px solid var(--gray-200);
}

/* === Page Header === */
.page-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 24px;
    flex-wrap: wrap;
}

.page-header h1 {
    margin: 0;
}

.btn-back {
    background: var(--gray-100);
    color: var(--gray-700);
    padding: 6px 14px;
    border-radius: 6px;
    font-size: 13px;
    transition: background 0.15s;
}

.btn-back:hover {
    background: var(--gray-200);
    color: var(--gray-900);
}

/* === Filtros === */
.filtros {
    background: #fff;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 16px 20px;
    margin-bottom: 20px;
}

.filtros-form {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    align-items: center;
}

.filtro-grupo {
    flex: 1;
    min-width: 160px;
}

.input-buscar,
.input-select,
.input-date {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 13px;
}

.input-buscar:focus,
.input-select:focus,
.input-date:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.btn-secondary {
    background: var(--gray-100);
    color: var(--gray-700);
    padding: 8px 16px;
    border-radius: 6px;
    font-size: 13px;
    border: 1px solid var(--gray-300);
}

.btn-secondary:hover {
    background: var(--gray-200);
}

/* === Detail Grid === */
.detail-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(380px, 1fr));
    gap: 20px;
    margin-bottom: 24px;
}

.detail-body {
    padding: 16px 20px;
}

.detail-row {
    display: flex;
    padding: 6px 0;
    border-bottom: 1px solid var(--gray-100);
    font-size: 13px;
}

.detail-row:last-child {
    border-bottom: none;
}

.detail-row .label {
    flex: 0 0 140px;
    color: var(--gray-500);
    font-weight: 500;
}

.detail-row.full {
    flex-direction: column;
    gap: 4px;
}

/* === Badges variants === */
.badge-success {
    background: var(--accent-light);
    color: #065f46;
}

.badge-danger {
    background: var(--danger-light);
    color: var(--danger);
}

.badge-neutral {
    background: var(--gray-200);
    color: var(--gray-700);
}

.badge-info {
    background: var(--primary-light);
    color: var(--primary);
}

.badge-warning {
    background: #fef3c7;
    color: #92400e;
}

/* === Small button === */
.btn-sm {
    display: inline-block;
    padding: 4px 10px;
    background: var(--primary-light);
    color: var(--primary);
    border-radius: 4px;
    font-size: 12px;
    font-weight: 500;
    transition: background 0.15s;
}

.btn-sm:hover {
    background: var(--primary);
    color: #fff;
}

/* === Paginacion === */
.paginacion {
    display: flex;
    justify-content: center;
    gap: 4px;
    margin: 20px 0;
    flex-wrap: wrap;
}

.pag-link {
    display: inline-block;
    padding: 6px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 4px;
    font-size: 13px;
    color: var(--gray-700);
    background: #fff;
    transition: all 0.15s;
}

.pag-link:hover {
    background: var(--gray-100);
    color: var(--gray-900);
}

.pag-link.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

/* === Table row variants === */
.row-paid {
    background: #f0fdf4;
}

.row-overdue {
    background: #fef2f2;
}

.row-total {
    background: var(--gray-50);
    border-top: 2px solid var(--gray-300);
}

/* === Mono text === */
.mono {
    font-family: 'SF Mono', Menlo, monospace;
    font-size: 12px;
}

.text-center {
    text-align: center;
}

.text-money {
    color: var(--accent);
    font-weight: 600;
}

.text-bold {
    font-weight: 600;
}

.truncate {
    max-width: 200px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* === Responsive === */
@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
    }

    .sidebar.open {
        transform: translateX(0);
    }

    .main-content {
        margin-left: 0;
    }

    .menu-toggle {
        display: block;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .content {
        padding: 16px;
    }
}

@media (max-width: 480px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }

    .user-info {
        display: none;
    }
}

/* === Forms === */
.form-body {
    padding: 16px 20px;
}

.form-group {
    margin-bottom: 16px;
    flex: 1;
}

.form-group label {
    display: block;
    margin-bottom: 4px;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.form-group input[readonly] {
    background: var(--gray-100);
    color: var(--gray-500);
}

.form-row {
    display: flex;
    gap: 16px;
}

.form-actions {
    display: flex;
    gap: 12px;
    margin: 24px 0;
}

/* === Dynamic articles list === */
.articulo-row {
    display: flex;
    gap: 12px;
    align-items: end;
    padding: 8px 0;
    border-bottom: 1px solid var(--gray-100);
}

.articulo-row .form-group {
    margin-bottom: 0;
}

.btn-remove {
    background: var(--danger-light);
    color: var(--danger);
    border: none;
    border-radius: 4px;
    padding: 8px 12px;
    cursor: pointer;
    font-size: 14px;
    min-width: 36px;
}

.btn-remove:hover {
    background: var(--danger);
    color: #fff;
}

.btn-add {
    background: var(--accent-light);
    color: #065f46;
    border: none;
    border-radius: 6px;
    padding: 8px 16px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 500;
    margin-top: 8px;
}

.btn-add:hover {
    background: var(--accent);
    color: #fff;
}

.btn-success {
    background: var(--accent);
    color: #fff;
    padding: 10px 20px;
    border-radius: 6px;
    border: none;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
}

.btn-success:hover {
    background: #047857;
}

.resumen-calculo {
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 16px 20px;
    margin-top: 16px;
}

.resumen-calculo .detail-row {
    font-size: 14px;
}

.resumen-calculo .total {
    font-size: 18px;
    font-weight: 700;
    color: var(--primary);
    border-top: 2px solid var(--gray-300);
    padding-top: 8px;
    margin-top: 4px;
}

@media (max-width: 768px) {
    .form-row {
        flex-direction: column;
        gap: 0;
    }
    .articulo-row {
        flex-wrap: wrap;
    }
}