/* ==================== CSS VARIABLES & RESET ==================== */
:root {
    --primary: #4F46E5;
    --primary-light: #818CF8;
    --primary-dark: #3730A3;
    --secondary: #F59E0B;
    --secondary-light: #FCD34D;
    --success: #10B981;
    --danger: #EF4444;
    --warning: #F59E0B;
    --info: #3B82F6;
    --dark: #1F2937;
    --gray-900: #111827;
    --gray-800: #1F2937;
    --gray-700: #374151;
    --gray-600: #4B5563;
    --gray-500: #6B7280;
    --gray-400: #9CA3AF;
    --gray-300: #D1D5DB;
    --gray-200: #E5E7EB;
    --gray-100: #F3F4F6;
    --gray-50: #F9FAFB;
    --white: #FFFFFF;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
    --shadow-xl: 0 20px 25px rgba(0,0,0,0.1), 0 10px 10px rgba(0,0,0,0.04);
    --radius-sm: 6px;
    --radius: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --transition: all 0.3s ease;
    --font: 'Segoe UI', system-ui, -apple-system, sans-serif;
}

/* Dark theme */
[data-theme="dark"] {
    --primary: #818CF8;
    --primary-light: #A5B4FC;
    --primary-dark: #6366F1;
    --dark: #F9FAFB;
    --gray-900: #F9FAFB;
    --gray-800: #F3F4F6;
    --gray-700: #E5E7EB;
    --gray-600: #D1D5DB;
    --gray-500: #9CA3AF;
    --gray-400: #6B7280;
    --gray-300: #4B5563;
    --gray-200: #374151;
    --gray-100: #1F2937;
    --gray-50: #111827;
    --white: #0F172A;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
    --shadow: 0 1px 3px rgba(0,0,0,0.4);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.3);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.3);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font);
    background: var(--gray-50);
    color: var(--gray-800);
    line-height: 1.6;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
}

img {
    max-width: 100%;
    display: block;
}

button {
    cursor: pointer;
    border: none;
    outline: none;
    font-family: inherit;
    font-size: inherit;
}

input, select, textarea {
    font-family: inherit;
    font-size: inherit;
    outline: none;
}

ul, ol {
    list-style: none;
}

/* ==================== UTILITY CLASSES ==================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.flex {
    display: flex;
}

.flex-center {
    display: flex;
    align-items: center;
    justify-content: center;
}

.flex-between {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.flex-col {
    display: flex;
    flex-direction: column;
}

.gap-1 { gap: 8px; }
.gap-2 { gap: 16px; }
.gap-3 { gap: 24px; }

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

.text-sm { font-size: 0.875rem; }
.text-xs { font-size: 0.75rem; }
.text-lg { font-size: 1.125rem; }
.text-xl { font-size: 1.25rem; }
.text-2xl { font-size: 1.5rem; }
.text-3xl { font-size: 1.875rem; }

.font-bold { font-weight: 700; }
.font-semibold { font-weight: 600; }
.font-medium { font-weight: 500; }

.text-primary { color: var(--primary); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-warning { color: var(--warning); }
.text-muted { color: var(--gray-500); }

.bg-primary { background: var(--primary); }
.bg-success { background: var(--success); }
.bg-danger { background: var(--danger); }
.bg-warning { background: var(--warning); }

.w-full { width: 100%; }
.h-full { height: 100%; }

.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }

.p-1 { padding: 8px; }
.p-2 { padding: 16px; }
.p-3 { padding: 24px; }

.rounded { border-radius: var(--radius); }
.rounded-md { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-full { border-radius: 50%; }

.hidden { display: none !important; }
.overflow-hidden { overflow: hidden; }

.truncate {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* ==================== BUTTONS ==================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.875rem;
    transition: var(--transition);
    border: 2px solid transparent;
    white-space: nowrap;
}

.btn:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn:active {
    transform: translateY(0);
}

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

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

.btn-secondary {
    background: var(--gray-200);
    color: var(--gray-700);
}

.btn-secondary:hover {
    background: var(--gray-300);
}

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

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

.btn-warning {
    background: var(--warning);
    color: white;
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
}

.btn-ghost {
    background: transparent;
    color: var(--gray-600);
}

.btn-ghost:hover {
    background: var(--gray-100);
}

.btn-sm {
    padding: 6px 12px;
    font-size: 0.8rem;
}

.btn-lg {
    padding: 14px 28px;
    font-size: 1rem;
}

.btn-icon {
    width: 40px;
    height: 40px;
    padding: 0;
    border-radius: var(--radius);
}

.btn-icon.sm {
    width: 32px;
    height: 32px;
}

/* ==================== FORM ELEMENTS ==================== */
.form-group {
    margin-bottom: 16px;
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 6px;
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 10px 14px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    background: var(--white);
    color: var(--gray-800);
    transition: var(--transition);
    font-size: 0.9rem;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.form-input::placeholder {
    color: var(--gray-400);
}

.form-textarea {
    resize: vertical;
    min-height: 80px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

/* ==================== CARDS ==================== */
.card {
    background: var(--white);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.card-header {
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.card-body {
    padding: 20px;
}

.card-footer {
    padding: 16px 20px;
    border-top: 1px solid var(--gray-200);
}

/* ==================== BADGES ==================== */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 2px 10px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-primary {
    background: rgba(79, 70, 229, 0.1);
    color: var(--primary);
}

.badge-success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

.badge-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
}

.badge-warning {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning);
}

/* ==================== MODAL ==================== */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    padding: 20px;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 560px;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.9) translateY(20px);
    transition: var(--transition);
}

.modal-overlay.active .modal {
    transform: scale(1) translateY(0);
}

.modal-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--gray-200);
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    background: var(--white);
    z-index: 1;
}

.modal-header h3 {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--gray-900);
}

.modal-close {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius);
    background: var(--gray-100);
    color: var(--gray-500);
    cursor: pointer;
    transition: var(--transition);
    border: none;
}

.modal-close:hover {
    background: var(--gray-200);
    color: var(--gray-700);
}

.modal-body {
    padding: 24px;
}

.modal-footer {
    padding: 16px 24px;
    border-top: 1px solid var(--gray-200);
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 12px;
}

/* ==================== TABLE ==================== */
.table-wrapper {
    overflow-x: auto;
    border-radius: var(--radius-md);
}

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

.table th,
.table td {
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid var(--gray-200);
}

.table th {
    background: var(--gray-50);
    font-weight: 600;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--gray-600);
}

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

.table td {
    font-size: 0.875rem;
    color: var(--gray-700);
}

/* ==================== TOAST NOTIFICATION ==================== */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 9999;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.toast {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 20px;
    border-radius: var(--radius-md);
    background: var(--white);
    box-shadow: var(--shadow-lg);
    min-width: 300px;
    max-width: 420px;
    animation: slideInRight 0.3s ease, fadeOut 0.3s ease 2.7s forwards;
    border-left: 4px solid var(--primary);
}

.toast.success { border-left-color: var(--success); }
.toast.error { border-left-color: var(--danger); }
.toast.warning { border-left-color: var(--warning); }

.toast-icon {
    font-size: 1.25rem;
    flex-shrink: 0;
}

.toast-message {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--gray-700);
}

@keyframes slideInRight {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

@keyframes fadeOut {
    from { opacity: 1; }
    to { opacity: 0; transform: translateX(50px); }
}

/* ==================== EMPTY STATE ==================== */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 60px 20px;
    text-align: center;
}

.empty-state i {
    font-size: 4rem;
    color: var(--gray-300);
    margin-bottom: 16px;
}

.empty-state h3 {
    font-size: 1.125rem;
    color: var(--gray-600);
    margin-bottom: 8px;
}

.empty-state p {
    font-size: 0.875rem;
    color: var(--gray-400);
}

/* ==================== SCROLLBAR ==================== */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: var(--gray-100);
}

::-webkit-scrollbar-thumb {
    background: var(--gray-300);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-400);
}

/* ==================== ANIMATIONS ==================== */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes scaleIn {
    from { opacity: 0; transform: scale(0.9); }
    to { opacity: 1; transform: scale(1); }
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.animate-fadeIn { animation: fadeIn 0.3s ease; }
.animate-slideUp { animation: slideUp 0.4s ease; }
.animate-slideDown { animation: slideDown 0.4s ease; }
.animate-scaleIn { animation: scaleIn 0.3s ease; }

/* ==================== RESPONSIVE ==================== */
@media (max-width: 768px) {
    .form-row {
        grid-template-columns: 1fr;
    }

    .modal {
        max-width: 100%;
        margin: 10px;
    }

    .toast {
        min-width: auto;
        max-width: calc(100vw - 40px);
    }
}

/* ==================== LOADING SPINNER ==================== */
.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--gray-200);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

/* ==================== PRODUCT IMAGE PLACEHOLDER ==================== */
.product-img-placeholder {
    width: 100%;
    aspect-ratio: 1;
    background: linear-gradient(135deg, var(--gray-100), var(--gray-200));
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-400);
    font-size: 2.5rem;
}

/* ==================== QUANTITY CONTROL ==================== */
.qty-control {
    display: flex;
    align-items: center;
    gap: 0;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    overflow: hidden;
}

.qty-control button {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gray-50);
    color: var(--gray-600);
    border: none;
    cursor: pointer;
    transition: var(--transition);
    font-size: 1rem;
}

.qty-control button:hover {
    background: var(--gray-200);
}

.qty-control input {
    width: 48px;
    height: 36px;
    text-align: center;
    border: none;
    border-left: 1px solid var(--gray-200);
    border-right: 1px solid var(--gray-200);
    font-weight: 600;
    font-size: 0.875rem;
    background: var(--white);
    color: var(--gray-800);
}

.qty-control input::-webkit-inner-spin-button,
.qty-control input::-webkit-outer-spin-button {
    -webkit-appearance: none;
}

/* ==================== SEARCH BAR ==================== */
.search-bar {
    position: relative;
    width: 100%;
}

.search-bar input {
    width: 100%;
    padding: 10px 14px 10px 42px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-lg);
    background: var(--white);
    color: var(--gray-800);
    transition: var(--transition);
    font-size: 0.9rem;
}

.search-bar input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.search-bar i {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray-400);
}

/* ==================== TABS ==================== */
.tabs {
    display: flex;
    gap: 4px;
    background: var(--gray-100);
    padding: 4px;
    border-radius: var(--radius-md);
    overflow-x: auto;
}

.tab {
    padding: 8px 16px;
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--gray-500);
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
    border: none;
    background: transparent;
}

.tab:hover {
    color: var(--gray-700);
}

.tab.active {
    background: var(--white);
    color: var(--primary);
    box-shadow: var(--shadow-sm);
    font-weight: 600;
}