* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
        'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    background-color: #f5f5f5;
    min-height: 100vh;
}

.app-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 2rem 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.app-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.header-left {
    display: flex;
    align-items: center;
}

.app-header h1 {
    font-size: 2rem;
    font-weight: 600;
    margin: 0;
}

/* Navigation Menu */
.main-nav {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.nav-link {
    color: white;
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    transition: background-color 0.2s ease;
}

.nav-link:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.nav-link.active {
    background-color: rgba(255, 255, 255, 0.2);
}

.nav-user {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding-left: 1rem;
    border-left: 1px solid rgba(255, 255, 255, 0.3);
}

.user-name {
    font-size: 0.9rem;
    opacity: 0.9;
}

.logout-btn {
    background-color: rgba(255, 255, 255, 0.2);
    padding: 0.5rem 1rem;
}

.logout-btn:hover {
    background-color: rgba(255, 255, 255, 0.3);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

main {
    padding: 2rem 0;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.page-header h2 {
    font-size: 1.75rem;
    color: #1f2937;
    font-weight: 600;
}

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-primary {
    background-color: white;
    color: #667eea;
}

.btn-primary:hover {
    background-color: #f0f0f0;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.btn-danger {
    background-color: #ef4444;
    color: white;
}

.btn-danger:hover {
    background-color: #dc2626;
}

.btn-secondary {
    background-color: #6b7280;
    color: white;
}

.btn-secondary:hover {
    background-color: #4b5563;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

/* Stats */
.stats-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    border-radius: 12px;
    padding: 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

.stat-card.warning {
    border-left: 4px solid #f59e0b;
}

.stat-icon {
    font-size: 2.5rem;
}

.stat-content {
    flex: 1;
}

.stat-value {
    font-size: 1.8rem;
    font-weight: 700;
    color: #1f2937;
    margin-bottom: 0.25rem;
}

.stat-label {
    font-size: 0.875rem;
    color: #6b7280;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Search Bar */
.search-bar-container {
    margin-bottom: 2rem;
}

.search-bar {
    position: relative;
    display: flex;
    align-items: center;
    background: white;
    border-radius: 12px;
    padding: 0.75rem 1rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.search-icon {
    font-size: 1.25rem;
    margin-right: 0.75rem;
    color: #6b7280;
}

.search-bar input {
    flex: 1;
    border: none;
    outline: none;
    font-size: 1rem;
    color: #1f2937;
}

.search-bar input::placeholder {
    color: #9ca3af;
}

.clear-search {
    background: none;
    border: none;
    font-size: 1.25rem;
    color: #6b7280;
    cursor: pointer;
    padding: 0.25rem;
    margin-left: 0.5rem;
    transition: color 0.2s ease;
}

.clear-search:hover {
    color: #1f2937;
}

/* Product List */
.product-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.product-card {
    background: white;
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.product-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

.product-card.low-stock {
    border-left: 4px solid #f59e0b;
}

.product-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
}

.product-name {
    font-size: 1.25rem;
    font-weight: 600;
    color: #1f2937;
    flex: 1;
}

.product-category {
    background: #e5e7eb;
    color: #4b5563;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 500;
    white-space: nowrap;
}

.product-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
    border-radius: 8px;
    background: #f3f4f6;
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.product-details {
    flex: 1;
}

.product-description {
    color: #6b7280;
    font-size: 0.875rem;
    margin-bottom: 1rem;
    line-height: 1.5;
}

.product-info {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

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

.info-label {
    font-size: 0.875rem;
    color: #6b7280;
    font-weight: 500;
}

.info-value {
    font-size: 0.875rem;
    color: #1f2937;
    font-weight: 600;
}

.info-value.price {
    color: #059669;
    font-size: 1rem;
}

.info-value.stock.warning {
    color: #f59e0b;
}

.product-actions {
    display: flex;
    gap: 0.75rem;
    padding-top: 1rem;
    border-top: 1px solid #e5e7eb;
}

.product-actions .btn {
    flex: 1;
}

.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.empty-state h2 {
    font-size: 1.5rem;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.empty-state p {
    color: #6b7280;
    font-size: 1rem;
}

.loading {
    text-align: center;
    padding: 3rem;
    font-size: 1.2rem;
    color: #666;
}

/* Modal */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 1rem;
}

.modal-content {
    background: white;
    border-radius: 12px;
    width: 100%;
    max-width: 600px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem;
    border-bottom: 1px solid #e5e7eb;
}

.modal-header h2 {
    font-size: 1.5rem;
    color: #1f2937;
    font-weight: 600;
}

.close-button {
    background: none;
    border: none;
    font-size: 1.5rem;
    color: #6b7280;
    cursor: pointer;
    padding: 0.25rem;
    line-height: 1;
    transition: color 0.2s ease;
}

.close-button:hover {
    color: #1f2937;
}

/* Form */
.product-form {
    padding: 1.5rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: #374151;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-group input.error,
.form-group textarea.error {
    border-color: #ef4444;
}

.error-message {
    display: block;
    margin-top: 0.25rem;
    font-size: 0.875rem;
    color: #ef4444;
}

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

.form-actions {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
    padding-top: 1rem;
    border-top: 1px solid #e5e7eb;
    margin-top: 1.5rem;
}

/* Responsive */
@media (max-width: 768px) {
    .app-header .container {
        flex-direction: column;
        gap: 1rem;
    }

    .app-header h1 {
        font-size: 1.5rem;
    }

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

    .product-list {
        grid-template-columns: 1fr;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .form-actions {
        flex-direction: column-reverse;
    }

    .form-actions .btn {
        width: 100%;
    }
    
    .main-nav {
        flex-direction: column;
        width: 100%;
        gap: 0.75rem;
    }
    
    .nav-user {
        border-left: none;
        border-top: 1px solid rgba(255, 255, 255, 0.3);
        padding-left: 0;
        padding-top: 0.75rem;
        width: 100%;
        justify-content: space-between;
    }
    
    .page-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
    
    .page-header .btn {
        width: 100%;
    }
}

/* Login Page Styles */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 2rem;
}

.login-card {
    background: white;
    border-radius: 12px;
    padding: 2.5rem;
    width: 100%;
    max-width: 400px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

.login-header {
    text-align: center;
    margin-bottom: 2rem;
}

.login-header h1 {
    font-size: 2rem;
    color: #1f2937;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.login-header p {
    color: #6b7280;
    font-size: 0.95rem;
}

.login-footer {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid #e5e7eb;
    text-align: center;
}

.login-info {
    font-size: 0.875rem;
    color: #6b7280;
    margin: 0;
}

.login-info strong {
    color: #374151;
}

.btn-block {
    width: 100%;
}

#login-error {
    background-color: #fee2e2;
    color: #991b1b;
    padding: 0.75rem;
    border-radius: 6px;
    font-size: 0.875rem;
    margin-bottom: 0.5rem;
}

/* Responsive Login */
@media (max-width: 480px) {
    .login-card {
        padding: 1.5rem;
    }
    
    .login-header h1 {
        font-size: 1.5rem;
    }
}