/* ==========================================================================
   RESET & VARIABLES
   ========================================================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Colores principales */
    --primary-color: #667eea;
    --primary-dark: #5a67d8;
    --secondary-color: #764ba2;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --info-color: #3b82f6;
    
    /* Colores de estado */
    --available-color: #10b981;
    --low-stock-color: #f59e0b;
    --out-of-stock-color: #ef4444;
    --sold-color: #8b5cf6;
    
    /* Colores de fondo */
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-dark: #1a202c;
    --bg-card: #ffffff;
    
    /* Colores de texto */
    --text-primary: #1a202c;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --text-white: #ffffff;
    
    /* Sombras */
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    /* Bordes */
    --border-radius: 8px;
    --border-radius-lg: 12px;
    --border-color: #e2e8f0;
    
    /* Espaciado */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Transiciones */
    --transition: all 0.2s ease-in-out;
    --transition-slow: all 0.3s ease-in-out;
}

/* ==========================================================================
   BASE STYLES
   ========================================================================== */
html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    font-size: 14px;
    overflow-x: hidden; /* Prevent horizontal scrolling on mobile */
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main-content {
    flex: 1;
    padding: var(--spacing-lg) 0;
    width: 100%;
}

img, video {
    max-width: 100%;
    height: auto;
}

/* ==========================================================================
   HEADER & NAVIGATION
   ========================================================================== */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--text-white);
    padding: var(--spacing-md) 0;
    box-shadow: var(--shadow-lg);
    position: sticky;
    top: 0;
    z-index: 1000;
    width: 100%;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    padding: 0 var(--spacing-sm);
}

.header h1 {
    font-size: 1.2rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.header h1 i {
    font-size: 1.1rem;
}

.user-info {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: var(--spacing-xs);
    font-size: 0.8rem;
}

.stock-indicator {
    background: rgba(255, 255, 255, 0.2);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius);
    backdrop-filter: blur(10px);
    font-size: 0.8rem;
}

/* Tabs Navigation */
.nav-tabs {
    display: flex;
    background: var(--bg-secondary);
    border-bottom: 2px solid var(--border-color);
    padding: 0 var(--spacing-sm);
    gap: var(--spacing-xs);
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
    -webkit-overflow-scrolling: touch; /* Smooth scrolling on iOS */
}

.nav-tabs::-webkit-scrollbar {
    display: none;
}

.tab-button {
    background: transparent;
    border: none;
    padding: var(--spacing-md) var(--spacing-md);
    cursor: pointer;
    font-weight: 500;
    color: var(--text-secondary);
    border-bottom: 3px solid transparent;
    transition: var(--transition);
    white-space: nowrap;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    min-width: fit-content;
    min-height: 44px; /* Ensure touch target size */
}

.tab-button:hover {
    color: var(--primary-color);
    background: rgba(102, 126, 234, 0.05);
}

.tab-button.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
    background: rgba(102, 126, 234, 0.1);
}

.tab-button i {
    font-size: 1rem;
}

.tab-content {
    display: none;
    animation: fadeIn 0.3s ease-in-out;
}

.tab-content.active {
    display: block;
}

/* ==========================================================================
   SECTION HEADERS & CONTROLS
   ========================================================================== */
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
    gap: var(--spacing-md);
    width: 100%;
}

.section-header h2 {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.header-controls {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    width: 100%;
}

.header-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.info-badge {
    background: rgba(59, 130, 246, 0.1);
    color: var(--info-color);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius);
    font-size: 0.8rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.warning-badge {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius);
    font-size: 0.8rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

/* ==========================================================================
   SEARCH & FILTERS
   ========================================================================== */
/* Search control */
.search-container {
    position: relative;
    width: 100%;
    max-width: 250px;
}

.search-container input {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-lg) var(--spacing-sm) 2.5rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    transition: var(--transition);
    min-height: 44px; /* Better touch target */
}

.search-container input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.search-container i {
    position: absolute;
    left: var(--spacing-md);
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

/* Filter controls */
.filter-controls {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
    position: relative;
    flex-wrap: wrap;
    width: 100%;
}

.filter-controls select {
    padding: var(--spacing-sm) var(--spacing-lg) var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    appearance: none;
    cursor: pointer;
    transition: var(--transition);
    min-width: 160px;
    font-family: inherit;
    min-height: 44px; /* Better touch target */
    width: 100%;
}

.filter-controls select:after,
.filter-controls::after {
    content: '\f107';
    font-family: 'Font Awesome 5 Free';
    font-weight: 900;
    position: absolute;
    right: var(--spacing-md);
    top: 50%;
    transform: translateY(-50%);
    pointer-events: none;
    color: var(--text-muted);
}

.filter-controls select:hover {
    border-color: var(--primary-color);
    background-color: rgba(102, 126, 234, 0.02);
}

.filter-controls select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.filter-controls select option {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    padding: var(--spacing-md);
}

/* Filter container */
.filter-container {
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
    flex-wrap: wrap;
    width: 100%;
}

.filter-container input[type="date"] {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    min-width: 140px;
    font-family: inherit;
    min-height: 44px; /* Better touch target */
    width: 100%;
}

.filter-container select {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    appearance: none;
    cursor: pointer;
    transition: var(--transition);
    min-width: 170px;
    font-family: inherit;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='%23718096'%3E%3Cpath d='M7 10l5 5 5-5z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 10px center;
    background-size: 16px;
    padding-right: 30px;
    min-height: 44px; /* Better touch target */
    width: 100%;
}

.filter-container input:hover,
.filter-container select:hover {
    border-color: var(--primary-color);
    background-color: rgba(102, 126, 234, 0.02);
}

.filter-container input:focus,
.filter-container select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.filter-container select option {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    padding: var(--spacing-md);
}

/* ==========================================================================
   BUTTONS
   ========================================================================== */
.btn {
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-weight: 500;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    transition: var(--transition);
    font-size: 0.9rem;
    min-height: 44px; /* Better touch target */
    min-width: 44px; /* Better touch target */
    white-space: nowrap;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

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

.btn-primary:hover:not(:disabled) {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--text-muted);
    color: var(--text-white);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--text-secondary);
}

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

.btn-success:hover:not(:disabled) {
    background: #059669;
}

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

.btn-danger:hover:not(:disabled) {
    background: #dc2626;
}

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

.btn-warning:hover:not(:disabled) {
    background: #d97706;
}

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

.btn-info:hover:not(:disabled) {
    background: #2563eb;
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.btn-outline:hover:not(:disabled) {
    background: var(--bg-primary);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-small {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.8rem;
    min-height: 36px; /* Still ensure a good touch target */
}

.action-buttons {
    display: flex;
    gap: var(--spacing-xs);
    justify-content: center;
    flex-wrap: wrap;
}

/* ==========================================================================
   FORMS
   ========================================================================== */
.form-container {
    background: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    max-width: 800px;
    margin: 0 auto;
    width: 100%;
}

.product-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
    width: 100%;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    width: 100%;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    width: 100%;
}

.form-group label {
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    transition: var(--transition);
    font-family: inherit;
    width: 100%;
    min-height: 44px; /* Better touch target */
}

.form-group textarea {
    min-height: 100px;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-hint {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: var(--spacing-xs);
}

.inventory-section {
    border: 2px dashed var(--border-color);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    background: rgba(102, 126, 234, 0.02);
    width: 100%;
}

.form-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    width: 100%;
    flex-wrap: wrap;
}

.input-group {
    display: flex;
    gap: var(--spacing-sm);
    width: 100%;
    flex-wrap: wrap;
}

.input-group input {
    flex: 1;
    min-width: 0; /* Fix for flex items */
}

/* ==========================================================================
   TABLES
   ========================================================================== */
.table-container {
    background: var(--bg-secondary);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    overflow-x: auto; /* Allow horizontal scrolling for tables */
    -webkit-overflow-scrolling: touch; /* Smooth scrolling on iOS */
    width: 100%;
    margin-bottom: var(--spacing-lg);
}

table {
    width: 100%;
    border-collapse: collapse;
    min-width: 650px; /* Ensure table doesn't shrink too much */
}

thead {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--text-white);
}

thead th {
    padding: var(--spacing-md);
    text-align: left;
    font-weight: 600;
    font-size: 0.9rem;
    position: sticky;
    top: 0;
    z-index: 10;
}

tbody tr {
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
}

tbody tr:hover {
    background: rgba(102, 126, 234, 0.02);
}

tbody tr:last-child {
    border-bottom: none;
}

tbody td {
    padding: var(--spacing-md);
    font-size: 0.9rem;
    vertical-align: middle;
}

.no-data-message {
    text-align: center;
    padding: var(--spacing-2xl);
    color: var(--text-muted);
}

.no-data-message i {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
    opacity: 0.5;
}

.no-data-message p {
    margin-bottom: var(--spacing-lg);
    font-size: 1.1rem;
}

/* ==========================================================================
   STATUS INDICATORS & BADGES
   ========================================================================== */
/* Status badges */
.status-badge {
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    white-space: nowrap;
}

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

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

.status-out-of-stock {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error-color);
}

.status-sold {
    background: rgba(139, 92, 246, 0.1);
    color: var(--sold-color);
}

.status-category {
    background: rgba(102, 126, 234, 0.1);
    color: var(--primary-color);
}

/* Quantity display */
.quantity-display {
    font-weight: 600;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius);
    background: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
    display: inline-flex;
    align-items: center;
    white-space: nowrap;
}

.quantity-display.low-stock {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
}

/* Highlights */
.price-highlight {
    color: var(--success-color);
    font-weight: 600;
}

.total-highlight {
    color: var(--primary-color);
    font-weight: 700;
    font-size: 1.05rem;
}

.stock-highlight {
    color: var(--info-color);
    font-weight: 600;
}

.total-value {
    color: var(--primary-color);
}

/* Connection status */
.connection-status {
    position: fixed;
    bottom: var(--spacing-md);
    right: var(--spacing-md);
    background: var(--bg-secondary);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.8rem;
    z-index: 1000;
    transition: var(--transition);
    max-width: 90vw;
}

.connection-status.connected {
    border-left: 4px solid var(--success-color);
}

.connection-status.offline {
    border-left: 4px solid var(--warning-color);
}

.connection-status.error {
    border-left: 4px solid var(--error-color);
}

.connection-status.connecting {
    border-left: 4px solid var(--info-color);
}

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

.connection-status.connected .status-icon i {
    color: var(--success-color);
}

.connection-status.offline .status-icon i {
    color: var(--warning-color);
}

.connection-status.error .status-icon i {
    color: var(--error-color);
}

.connection-status.connecting .status-icon i {
    color: var(--info-color);
    animation: pulse 1.5s infinite;
}

.status-icon i {
    font-size: 0.8rem;
}

/* Alerts */
.stock-alerts {
    margin: var(--spacing-md) 0;
    width: 100%;
}

.alert {
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    position: relative;
    animation: slideDown 0.3s ease-out;
    width: 100%;
    flex-wrap: wrap;
}

.alert-warning {
    background: #fef3cd;
    color: #856404;
    border: 1px solid #faebcc;
}

.alert-close {
    background: none;
    border: none;
    color: inherit;
    cursor: pointer;
    margin-left: auto;
    padding: var(--spacing-xs);
    border-radius: var(--border-radius);
    transition: var(--transition);
    min-height: 36px;
    min-width: 36px;
}

.alert-close:hover {
    background: rgba(0, 0, 0, 0.1);
}

/* Loading indicator */
.loading-indicator {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    backdrop-filter: blur(5px);
    gap: 10px;
    padding: 2rem;
    color: #6b7280;
    font-size: 0.9rem;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: var(--spacing-md);
}

.loading-indicator p {
    color: var(--text-white);
    font-weight: 500;
    text-align: center;
}

.loading {
    width: 20px;
    height: 20px;
    border: 2px solid var(--border-color);
    border-top: 2px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    display: inline-block;
}

/* ==========================================================================
   CARDS & CONTAINERS
   ========================================================================== */
/* Sell Form */
.sell-form {
    background: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    max-width: 600px;
    margin: 0 auto;
    width: 100%;
}

.product-preview {
    background: rgba(16, 185, 129, 0.05);
    border: 2px solid var(--success-color);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-lg);
    margin-top: var(--spacing-lg);
    animation: slideDown 0.3s ease-out;
    width: 100%;
}

.product-preview h3 {
    color: var(--success-color);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.product-details {
    display: grid;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
    width: 100%;
}

.detail-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid rgba(16, 185, 129, 0.1);
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

.sell-quantity-section {
    background: rgba(102, 126, 234, 0.05);
    border: 1px solid rgba(102, 126, 234, 0.2);
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
    width: 100%;
}

.quantity-controls {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-sm);
    flex-wrap: wrap;
    justify-content: center;
}

.quantity-btn {
    background: var(--primary-color);
    color: var(--text-white);
    border: none;
    width: 44px;
    height: 44px;
    border-radius: var(--border-radius);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

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

.quantity-controls input {
    width: 80px;
    text-align: center;
    font-weight: 600;
    min-height: 44px;
}

.sale-summary {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-md);
    margin-top: var(--spacing-md);
    width: 100%;
}

.summary-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

.summary-row.total-row {
    border-top: 2px solid var(--border-color);
    margin-top: var(--spacing-sm);
    padding-top: var(--spacing-md);
    font-size: 1.1rem;
}

.preview-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    margin-top: var(--spacing-lg);
    flex-wrap: wrap;
    width: 100%;
}

/* Stats Cards */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
    width: 100%;
}

.stat-card {
    background: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    transition: var(--transition);
    border-left: 4px solid var(--primary-color);
    width: 100%;
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--text-white);
    background: var(--primary-color);
    flex-shrink: 0;
}

.stat-icon.available {
    background: var(--success-color);
}

.stat-icon.sold {
    background: var(--sold-color);
}

.stat-icon.revenue {
    background: var(--warning-color);
}

.stat-content {
    flex: 1;
    min-width: 0; /* Fix for flex items */
}

.stat-content h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
    word-wrap: break-word;
}

.stat-content p {
    color: var(--text-secondary);
    font-weight: 500;
}

/* Summary cards */
.sales-summary {
    margin-top: var(--spacing-lg);
    width: 100%;
}

.summary-card {
    background: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    width: 100%;
}

.summary-card h3 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.summary-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
    width: 100%;
}

.summary-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--border-color);
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

.summary-item:last-child {
    border-bottom: none;
}

.summary-item .label {
    color: var(--text-secondary);
    font-weight: 500;
}

.summary-item .value {
    font-weight: 600;
    color: var(--text-primary);
}

/* Chart cards */
.charts-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
    width: 100%;
}

.chart-card {
    background: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    width: 100%;
}

.chart-card h3 {
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.chart-wrapper {
    position: relative;
    height: 300px;
    width: 100%;
}

/* Mini stats */
.additional-stats {
    margin-top: var(--spacing-2xl);
    width: 100%;
}

.stats-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-md);
    width: 100%;
}

.mini-stat-card {
    background: var(--bg-secondary);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    text-align: center;
    border-top: 3px solid var(--primary-color);
    width: 100%;
}

.mini-stat-card h4 {
    color: var(--text-secondary);
    font-size: 0.8rem;
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.mini-stat-card p {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* ==========================================================================
   MODALS & TOASTS
   ========================================================================== */
/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    z-index: 10000;
    backdrop-filter: blur(5px);
}

.modal-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: var(--bg-secondary);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-xl);
    min-width: 300px;
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    animation: modalSlideIn 0.3s ease-out;
}

.modal-header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.modal-header h3 {
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--text-muted);
    padding: var(--spacing-sm);
    border-radius: var(--border-radius);
    transition: var(--transition);
    min-height: 44px;
    min-width: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close:hover {
    background: var(--bg-primary);
    color: var(--text-primary);
}

.modal-body {
    padding: var(--spacing-lg);
    width: 100%;
}

.sale-details {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: var(--spacing-md);
    margin: var(--spacing-md) 0;
    width: 100%;
}

.detail-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--border-color);
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

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

.detail-row.total {
    border-top: 2px solid var(--border-color);
    margin-top: var(--spacing-sm);
    padding-top: var(--spacing-md);
    font-size: 1.1rem;
}

.modal-footer {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
    flex-wrap: wrap;
    width: 100%;
}

/* Custom modal classes */
.reposition-modal ~ .modal-buttons {
    display: none;
}

.custom-modal .modal-footer {
    display: none;
}

/* Toast notifications */
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    z-index: 10001;
    min-width: 250px;
    max-width: 90vw;
    transform: translateX(400px);
    transition: var(--transition-slow);
    border-left: 4px solid var(--info-color);
}

.toast.show {
    transform: translateX(0);
}

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

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

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

.toast-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.toast-icon {
    font-size: 1.2rem;
    flex-shrink: 0;
}

.toast.success .toast-icon {
    color: var(--success-color);
}

.toast.error .toast-icon {
    color: var(--error-color);
}

.toast.warning .toast-icon {
    color: var(--warning-color);
}

.toast.info .toast-icon {
    color: var(--info-color);
}

.toast-message {
    flex: 1;
    font-weight: 500;
    min-width: 0; /* Fix for flex items */
    word-break: break-word;
}

.toast-close {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: var(--spacing-sm);
    border-radius: var(--border-radius);
    transition: var(--transition);
    min-height: 44px;
    min-width: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.toast-close:hover {
    background: var(--bg-primary);
    color: var(--text-primary);
}

/* Restock confirmation */
.restock-confirmation {
    text-align: left;
    width: 100%;
}

.restock-confirmation h4 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
}

.restock-confirmation p {
    margin-bottom: var(--spacing-sm);
}

.restock-confirmation hr {
    margin: var(--spacing-md) 0;
    border: none;
    border-top: 1px solid var(--border-color);
}

/* ==========================================================================
   FLOATING ACTION BUTTON
   ========================================================================== */
.fab-container {
    position: fixed;
    bottom: 20px;
    left: 20px;
    z-index: 1000;
}

.fab {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--text-white);
    border: none;
    cursor: pointer;
    font-size: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    transition: var(--transition);
    position: relative;
}

.fab:hover {
    transform: scale(1.1);
    box-shadow: var(--shadow-xl);
}

.fab-menu {
    position: absolute;
    bottom: 100%;
    left: 0;
    margin-bottom: var(--spacing-md);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: var(--transition);
}

.fab-menu.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.fab-option {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--bg-secondary);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
    cursor: pointer;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.fab-option:hover {
    background: var(--primary-color);
    color: var(--text-white);
    transform: scale(1.05);
}

/* ==========================================================================
   ANIMATIONS
   ========================================================================== */
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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

@keyframes bounce-in {
    0% {
        opacity: 0;
        transform: scale(0.3);
    }
    50% {
        transform: scale(1.05);
    }
    70% {
        transform: scale(0.9);
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}

@keyframes fade-in-up {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.7);
    }
    to {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
}

@keyframes pulse {
    0% { opacity: 0.6; }
    50% { opacity: 1; }
    100% { opacity: 0.6; }
}

.fade-in {
    animation: fadeIn 0.5s ease-in-out;
}

.bounce-in {
    animation: bounce-in 0.6s ease-out;
}

.fade-in-up {
    animation: fade-in-up 0.5s ease-out;
}

/* ==========================================================================
   UTILITY CLASSES
   ========================================================================== */
/* Text alignment */
.text-center { text-align: center !important; }
.text-left { text-align: left !important; }
.text-right { text-align: right !important; }

/* Font weights */
.font-weight-bold { font-weight: 700 !important; }
.font-weight-normal { font-weight: 400 !important; }

/* Text colors */
.text-success { color: var(--success-color) !important; }
.text-error { color: var(--error-color) !important; }
.text-warning { color: var(--warning-color) !important; }
.text-info { color: var(--info-color) !important; }
.text-muted { color: var(--text-muted) !important; }

/* Background colors */
.bg-success { background-color: var(--success-color) !important; }
.bg-error { background-color: var(--error-color) !important; }
.bg-warning { background-color: var(--warning-color) !important; }
.bg-info { background-color: var(--info-color) !important; }

/* Border colors */
.border-success { border-color: var(--success-color) !important; }
.border-error { border-color: var(--error-color) !important; }
.border-warning { border-color: var(--warning-color) !important; }
.border-info { border-color: var(--info-color) !important; }

/* Display */
.d-none { display: none !important; }
.d-block { display: block !important; }
.d-flex { display: flex !important; }
.d-grid { display: grid !important; }

/* Dimensions */
.w-100 { width: 100% !important; }
.h-100 { height: 100% !important; }

/* Spacing */
.m-0 { margin: 0 !important; }
.p-0 { padding: 0 !important; }

/* ==========================================================================
   RESPONSIVE DESIGN
   ========================================================================== */
/* Custom scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

/* Focus styles for accessibility */
.btn:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Medium screens */
@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .header-content {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-sm);
    }
    
    .user-info {
        align-items: center;
    }
    
    .nav-tabs {
        padding: 0;
    }
    
    .tab-button {
        padding: var(--spacing-sm) var(--spacing-md);
        font-size: 0.8rem;
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    .header-controls {
        width: 100%;
        justify-content: stretch;
    }
    
    .search-container {
        max-width: 100%;
        flex: 1;
    }
    
    .form-container {
        padding: var(--spacing-lg);
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .form-actions {
        flex-direction: column;
        align-items: stretch;
    }
    
    .form-actions .btn {
        width: 100%;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .charts-container {
        grid-template-columns: 1fr;
    }
    
    .summary-stats {
        grid-template-columns: 1fr;
    }
    
    .stats-row {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .modal-content {
        width: 95%;
    }
    
    .toast {
        max-width: 95%;
        right: 10px;
    }
    
    .fab-container {
        bottom: 20px;
        left: 20px;
    }
    
    .connection-status {
        bottom: 80px;
        right: 10px;
        max-width: 95%;
    }
}

/* Small screens */
@media (max-width: 600px) {
    .container {
        padding: 0 var(--spacing-xs);
    }
    
    .main-content {
        padding: var(--spacing-sm) 0;
    }
    
    .header h1 {
        font-size: 1.1rem;
    }
    
    .section-header h2 {
        font-size: 1.2rem;
    }
    
    .form-container,
    .sell-form,
    .table-container,
    .summary-card,
    .stat-card,
    .chart-card {
        padding: var(--spacing-md);
        border-radius: var(--border-radius);
        box-shadow: var(--shadow-sm);
    }
    
    .stat-card {
        flex-direction: column;
        text-align: center;
    }
    
    .stat-content {
        width: 100%;
    }
    
    .stats-row {
        grid-template-columns: 1fr;
    }
    
    .action-buttons {
        width: 100%;
        flex-direction: column;
    }
    
    .action-buttons .btn {
        width: 100%;
    }
    
    .preview-actions {
        flex-direction: column;
    }
    
    .preview-actions .btn {
        width: 100%;
    }
    
    .filter-container {
        flex-direction: column;
        align-items: stretch;
    }
    
    .filter-container input[type="date"],
    .filter-container select {
        width: 100%;
    }
    
    .modal-content {
        width: 100%;
        max-width: 100%;
        height: 100%;
        max-height: 100%;
        top: 0;
        left: 0;
        transform: none;
        border-radius: 0;
    }
    
    .modal-header,
    .modal-body,
    .modal-footer {
        padding: var(--spacing-md);
    }
    
    .modal-footer {
        flex-direction: column;
        align-items: stretch;
    }
    
    .modal-footer .btn {
        width: 100%;
    }
    
    .toast {
        left: 10px;
        right: 10px;
        max-width: calc(100% - 20px);
    }
    
    .connection-status {
        left: 10px;
        right: 10px;
        max-width: calc(100% - 20px);
        text-align: center;
    }
}

/* Extra small screens */
@media (max-width: 480px) {
    .tab-button {
        padding: var(--spacing-xs) var(--spacing-sm);
        font-size: 0.75rem;
        gap: var(--spacing-xs);
    }
    
    .tab-button i {
        font-size: 0.9rem;
    }
    
    .header h1 {
        font-size: 1rem;
    }
    
    .header-info {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .btn, 
    .btn-small {
        font-size: 0.8rem;
    }
    
    .detail-item,
    .summary-row,
    .summary-item {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .stat-content h3 {
        font-size: 1.3rem;
    }
    
    .chart-wrapper {
        height: 250px;
    }
}

/* Very small screens */
@media (max-width: 350px) {
    .header {
        padding: var(--spacing-xs) 0;
    }
    
    .section-header h2 {
        font-size: 1.1rem;
    }
    
    .tab-button {
        font-size: 0.7rem;
        padding: var(--spacing-xs) var(--spacing-xs);
    }
    
    .btn, 
    .btn-small {
        font-size: 0.75rem;
        padding: var(--spacing-xs) var(--spacing-xs);
    }
    
    .form-container, 
    .sell-form, 
    .summary-card, 
    .stat-card, 
    .chart-card {
        padding: var(--spacing-sm);
    }
    
    .stat-content h3 {
        font-size: 1.2rem;
    }
}

/* ==========================================================================
   DARK MODE
   ========================================================================== */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #0f172a;
        --bg-secondary: #1e293b;
        --bg-card: #1e293b;
        --text-primary: #f1f5f9;
        --text-secondary: #cbd5e1;
        --text-muted: #94a3b8;
        --border-color: #334155;
    }
    
    .header {
        background: linear-gradient(135deg, #1e293b, #0f172a);
    }
    
    .nav-tabs {
        background: var(--bg-secondary);
        border-bottom-color: var(--border-color);
    }
    
    .tab-button:hover {
        background: rgba(102, 126, 234, 0.1);
    }
    
    .tab-button.active {
        background: rgba(102, 126, 234, 0.2);
    }
    
    tbody tr:hover {
        background: rgba(102, 126, 234, 0.05);
    }
}

/* ==========================================================================
   PRINT STYLES
   ========================================================================== */
@media print {
    .header,
    .nav-tabs,
    .fab-container,
    .connection-status,
    .loading-indicator,
    .toast,
    .modal,
    .action-buttons {
        display: none !important;
    }
    
    .main-content {
        padding: 0;
    }
    
    .table-container {
        box-shadow: none;
        border: 1px solid #000;
    }
    
    .chart-card {
        page-break-inside: avoid;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* ==========================================================================
   ACCESSIBILITY
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ==========================================================================
   FOOTER
   ========================================================================== */
.footer {
    background: var(--bg-dark);
    color: var(--text-white);
    padding: var(--spacing-lg) 0;
    margin-top: var(--spacing-2xl);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    width: 100%;
}

.footer-content {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    align-items: center;
    padding: 0 var(--spacing-md);
}

.footer p {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin: 0;
}

.footer a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
    font-weight: 500;
}

.footer a:hover {
    color: var(--secondary-color);
    text-decoration: underline;
}

@media (max-width: 768px) {
    .footer {
        padding: var(--spacing-md) 0;
    }
    
    .footer p {
        font-size: 0.8rem;
    }
}