:root {
    --primary-color: #2196F3;
    --success-color: #4CAF50;
    --warning-color: #FFC107;
    --danger-color: #F44336;
    --purple-color: #9C27B0;
    --background-color: #f8f9fa;
    --surface-color: #ffffff;
    --text-primary: #212529;
    --text-secondary: #6c757d;
    --border-color: #dee2e6;
    --shadow: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-lg: 0 4px 12px rgba(0,0,0,0.15);
    --border-radius: 8px;
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    background-attachment: fixed;
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    padding-bottom: 80px;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(33, 150, 243, 0.05) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(76, 175, 80, 0.05) 0%, transparent 50%),
        radial-gradient(circle at 40% 80%, rgba(156, 39, 176, 0.05) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

#app {
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
}

.app-header {
    background: var(--surface-color);
    padding: var(--spacing-lg) var(--spacing-md);
    box-shadow: var(--shadow);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.95);
}

.app-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
}

.header-stats {
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
}

.header-stats span {
    font-weight: 600;
}

#total-value {
    font-size: 1.25rem;
    color: var(--text-primary);
}

.app-main {
    padding: var(--spacing-md);
}

.page {
    display: none;
}

.page.active {
    display: block;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-md) 0;
    border-bottom: 2px solid var(--border-color);
}

.page-header h2 {
    font-size: 1.75rem;
    color: var(--text-primary);
    font-weight: 700;
}

.portfolio-overview {
    margin-bottom: var(--spacing-xl);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.stat-card {
    background: var(--surface-color);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    border: 1px solid var(--border-color);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

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

.stat-icon {
    font-size: 1.5rem;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-color);
    border-radius: 50%;
    color: white;
}

.stat-info {
    display: flex;
    flex-direction: column;
}

.stat-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 500;
}

.stat-value {
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-primary);
}

.portfolio-chart {
    background: var(--surface-color);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin-bottom: var(--spacing-xl);
    border: 1px solid var(--border-color);
}

.portfolio-chart h3 {
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
    font-size: 1.25rem;
}

#portfolioChart {
    width: 100%;
    height: 200px;
    max-width: 100%;
}

.holdings-list, .portfolio-filters {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.holdings-list {
    padding: var(--spacing-lg);
}

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

.section-header h3 {
    font-size: 1.25rem;
    color: var(--text-primary);
}

.portfolio-filters {
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
}

.portfolio-filters select,
.portfolio-filters input {
    flex: 1;
    padding: var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
}

.portfolio-grid {
    display: grid;
    gap: var(--spacing-md);
}

.holding-item, .alert-item, .news-item {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.holding-item:hover, .alert-item:hover, .news-item:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

.holding-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.holding-info h4 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.holding-info .symbol {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-transform: uppercase;
}

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

.holding-price .current-price {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
}

.holding-price .price-change {
    font-size: 0.85rem;
    font-weight: 600;
}

.holding-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

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

.holding-stat .label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.holding-stat .value {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
}

.holding-actions {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.empty-state, .loading-state {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--text-secondary);
}

.empty-state i, .loading-state i {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.empty-state h4 {
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.change-positive {
    color: var(--success-color) !important;
}

.change-negative {
    color: var(--danger-color) !important;
}

.change-neutral {
    color: var(--text-secondary) !important;
}

.btn {
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all 0.2s ease;
    text-align: center;
    justify-content: center;
}

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

.btn-primary:hover {
    background: #1976D2;
    transform: translateY(-1px);
}

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

.btn-secondary:hover {
    background: #5a6268;
}

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

.btn-success:hover {
    background: #388E3C;
}

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

.btn-danger:hover {
    background: #D32F2F;
}

.btn-sm {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.8rem;
}

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

.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--surface-color);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: space-around;
    padding: var(--spacing-sm) 0;
    box-shadow: 0 -2px 10px rgba(0,0,0,0.1);
    z-index: 1000;
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.95);
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: var(--text-secondary);
    padding: var(--spacing-xs);
    border-radius: var(--border-radius);
    transition: all 0.2s ease;
    min-width: 60px;
}

.nav-item:hover {
    background: rgba(33, 150, 243, 0.1);
    color: var(--primary-color);
}

.nav-item.active {
    color: var(--primary-color);
    background: rgba(33, 150, 243, 0.1);
}

.nav-item i {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-xs);
}

.nav-item span {
    font-size: 0.7rem;
    font-weight: 600;
}

.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md);
}

.modal-content {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    animation: modalSlideIn 0.3s ease;
}

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

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

.modal-header h3 {
    color: var(--text-primary);
    font-size: 1.25rem;
}

.close-modal {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    padding: var(--spacing-xs);
    border-radius: 50%;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.close-modal:hover {
    background: rgba(0, 0, 0, 0.1);
    color: var(--text-primary);
}

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
    color: var(--text-primary);
}

.form-group input,
.form-group select {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(33, 150, 243, 0.1);
}

.modal-content form {
    padding: var(--spacing-lg);
}

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

.suggestions-list {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-top: none;
    border-radius: 0 0 var(--border-radius) var(--border-radius);
    max-height: 200px;
    overflow-y: auto;
    z-index: 10;
    display: none;
}

.suggestions-list.active {
    display: block;
}

.suggestion-item {
    padding: var(--spacing-md);
    cursor: pointer;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.suggestion-item:hover {
    background: rgba(33, 150, 243, 0.1);
}

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

.suggestion-info {
    flex: 1;
}

.suggestion-name {
    font-weight: 600;
    color: var(--text-primary);
}

.suggestion-symbol {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-transform: uppercase;
}

.suggestion-price {
    font-weight: 600;
    color: var(--primary-color);
}

.form-group {
    position: relative;
}

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

.alert-info h4 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.alert-info p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.alert-status {
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
}

.alert-status.active {
    background: var(--success-color);
    color: white;
}

.alert-status.triggered {
    background: var(--warning-color);
    color: white;
}

.alert-actions {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-sm);
}

.news-item {
    cursor: pointer;
}

.news-item h4 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    line-height: 1.4;
}

.news-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-sm);
}

.news-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.settings-section {
    background: var(--surface-color);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin-bottom: var(--spacing-lg);
    border: 1px solid var(--border-color);
}

.settings-section h3 {
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
    font-size: 1.1rem;
}

.settings-section select {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
}

.setting-item {
    margin-bottom: var(--spacing-md);
}

.setting-item label {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    cursor: pointer;
    font-weight: 500;
}

.setting-item input[type="checkbox"] {
    width: auto;
}

.transactions-section {
    margin-top: var(--spacing-xl);
    background: var(--surface-color);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}

.transactions-section h3 {
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
}

.transaction-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-sm);
}

.transaction-info h5 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.transaction-info p {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.transaction-amount {
    text-align: right;
    font-weight: 600;
}

.notification-banner {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--primary-color);
    color: white;
    padding: var(--spacing-md);
    z-index: 1500;
    box-shadow: var(--shadow);
}

.notification-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.notification-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.faq-section {
    margin-top: var(--spacing-xl);
}

.faq-section h2 {
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
    font-size: 1.5rem;
}

.faq-container {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.faq-item {
    border-bottom: 1px solid var(--border-color);
}

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

.faq-question {
    width: 100%;
    padding: var(--spacing-lg);
    background: none;
    border: none;
    text-align: left;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background-color 0.2s ease;
}

.faq-question:hover {
    background: rgba(33, 150, 243, 0.05);
}

.faq-question[aria-expanded="true"] {
    background: rgba(33, 150, 243, 0.1);
}

.faq-icon {
    font-size: 1.2rem;
    color: var(--primary-color);
    transition: transform 0.2s ease;
}

.faq-question[aria-expanded="true"] .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 var(--spacing-lg) var(--spacing-lg);
    color: var(--text-secondary);
    line-height: 1.6;
    animation: fadeIn 0.3s ease;
}

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

footer {
    text-align: center;
    padding: var(--spacing-lg);
    color: var(--text-secondary);
    font-size: 0.85rem;
    border-top: 1px solid var(--border-color);
    background: var(--surface-color);
    margin-top: var(--spacing-xl);
}

@media (max-width: 768px) {
    .app-main {
        padding: var(--spacing-sm);
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-sm);
    }
    
    .stat-card {
        padding: var(--spacing-md);
        flex-direction: column;
        text-align: center;
    }
    
    .stat-icon {
        width: 32px;
        height: 32px;
        font-size: 1.2rem;
    }
    
    .page-header {
        flex-direction: column;
        gap: var(--spacing-md);
        align-items: stretch;
    }
    
    .portfolio-filters {
        flex-direction: column;
    }
    
    .holding-stats {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .holding-actions {
        flex-direction: column;
    }
    
    .form-actions {
        flex-direction: column;
    }
    
    .notification-content {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }
    
    .modal-content {
        margin: var(--spacing-sm);
        max-height: calc(100vh - 2 * var(--spacing-sm));
    }
    
    #portfolioChart {
        height: 150px;
    }
}

@media (max-width: 480px) {
    .app-header {
        padding: var(--spacing-md) var(--spacing-sm);
    }
    
    .app-header h1 {
        font-size: 1.25rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .nav-item span {
        font-size: 0.65rem;
    }
    
    .nav-item i {
        font-size: 1.1rem;
    }
    
    .bottom-nav {
        padding: var(--spacing-xs) 0;
    }
}

.pulse {
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
    100% {
        opacity: 1;
    }
}

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

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

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

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