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

:root {
    /* Aurora UI Color Palette */
    --primary: #2196F3;
    --success: #4CAF50;
    --warning: #FFC107;
    --danger: #F44336;
    --purple: #9C27B0;
    
    /* Light Theme Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --text-primary: #212529;
    --text-secondary: #6c757d;
    --text-muted: #adb5bd;
    --border: #dee2e6;
    --shadow: rgba(0, 0, 0, 0.1);
    --shadow-hover: rgba(0, 0, 0, 0.15);
    
    /* Typography */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Transitions */
    --transition: all 0.2s ease-in-out;
    --transition-slow: all 0.3s ease-in-out;
}

/* Dark Theme */
[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --bg-tertiary: #404040;
    --text-primary: #ffffff;
    --text-secondary: #b0b0b0;
    --text-muted: #808080;
    --border: #404040;
    --shadow: rgba(0, 0, 0, 0.3);
    --shadow-hover: rgba(0, 0, 0, 0.4);
}

/* Base Styles */
body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: var(--transition);
}

.app {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header */
.header {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header__container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header__title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--primary);
}

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

/* Main Content */
.main {
    flex: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg);
    width: 100%;
}

/* Summary Cards */
.summary {
    margin-bottom: var(--spacing-2xl);
}

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

.card {
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: 0 2px 8px var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border);
}

.card:hover {
    box-shadow: 0 4px 12px var(--shadow-hover);
    transform: translateY(-2px);
}

.card__title {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.card__value {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    margin: 0;
}

.card--balance .card__value {
    color: var(--primary);
}

.card--income .card__value {
    color: var(--success);
}

.card--expense .card__value {
    color: var(--danger);
}

/* Form Section */
.form-section {
    margin-bottom: var(--spacing-2xl);
}

.form-container {
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: 0 2px 8px var(--shadow);
    border: 1px solid var(--border);
}

.form-section__title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
}

.form__row {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

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

.form__group--submit {
    flex-direction: row;
    gap: var(--spacing-sm);
    align-items: flex-end;
}

.form__label {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

.form__input,
.form__select {
    padding: var(--spacing-md);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: var(--transition);
    width: 100%;
}

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

.form__input:invalid {
    border-color: var(--danger);
}

/* Buttons */
.btn {
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    text-decoration: none;
    white-space: nowrap;
}

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

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

.btn--primary:hover:not(:disabled) {
    background-color: #1976D2;
    transform: translateY(-1px);
}

.btn--secondary {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border);
}

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

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

.btn--success:hover:not(:disabled) {
    background-color: #388E3C;
}

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

.btn--danger:hover:not(:disabled) {
    background-color: #D32F2F;
}

.btn--icon {
    padding: var(--spacing-sm);
    font-size: var(--font-size-lg);
    min-width: auto;
}

/* Theme Toggle */
.theme-toggle__icon {
    transition: var(--transition);
}

[data-theme="dark"] .theme-toggle__icon {
    transform: rotate(180deg);
}

/* Filters */
.filters {
    margin-bottom: var(--spacing-2xl);
}

.filters__container {
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: 0 2px 8px var(--shadow);
    border: 1px solid var(--border);
}

.filters__title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.filters__controls {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
    align-items: end;
}

/* Goals Section */
.goals {
    margin-bottom: var(--spacing-2xl);
}

.goals__container {
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: 0 2px 8px var(--shadow);
    border: 1px solid var(--border);
}

.goals__title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.goal-input {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.goal-input .form__input {
    flex: 1;
}

.goal-progress {
    margin-top: var(--spacing-md);
}

.progress-bar {
    width: 100%;
    height: 20px;
    background-color: var(--bg-tertiary);
    border-radius: var(--radius-xl);
    overflow: hidden;
    margin-bottom: var(--spacing-sm);
}

.progress-bar__fill {
    height: 100%;
    background: linear-gradient(90deg, var(--success), var(--primary));
    transition: width 0.5s ease-in-out;
    border-radius: var(--radius-xl);
}

.goal-text {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    text-align: center;
}

/* Transactions */
.transactions {
    margin-bottom: var(--spacing-2xl);
}

.transactions__container {
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: 0 2px 8px var(--shadow);
    border: 1px solid var(--border);
}

.transactions__header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.transactions__title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
}

.transactions__stats {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.transactions__list {
    max-height: 600px;
    overflow-y: auto;
}

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

.transaction-item:hover {
    box-shadow: 0 2px 8px var(--shadow);
    transform: translateY(-1px);
}

.transaction-item--income {
    border-left: 4px solid var(--success);
}

.transaction-item--expense {
    border-left: 4px solid var(--danger);
}

.transaction__info {
    flex: 1;
}

.transaction__description {
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
}

.transaction__details {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.transaction__amount {
    font-size: var(--font-size-lg);
    font-weight: 700;
    margin-right: var(--spacing-md);
}

.transaction__amount--income {
    color: var(--success);
}

.transaction__amount--expense {
    color: var(--danger);
}

.transaction__actions {
    display: flex;
    gap: var(--spacing-xs);
}

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

.empty-state {
    text-align: center;
    padding: var(--spacing-2xl);
    color: var(--text-muted);
}

.empty-state p:first-child {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-sm);
}

/* Charts */
.charts {
    margin-bottom: var(--spacing-2xl);
}

.charts__container {
    background-color: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: 0 2px 8px var(--shadow);
    border: 1px solid var(--border);
}

.charts__title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    color: var(--text-primary);
}

.charts__grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.chart-card {
    background-color: var(--bg-primary);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    border: 1px solid var(--border);
}

.chart-card__title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.chart {
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.chart__empty {
    color: var(--text-muted);
    text-align: center;
}

.chart__item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--border);
}

.chart__item:last-child {
    border-bottom: none;
}

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

.chart__color {
    width: 16px;
    height: 16px;
    border-radius: 50%;
}

.chart__value {
    font-weight: 600;
}

.analytics {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.analytics__item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--border);
}

.analytics__item:last-child {
    border-bottom: none;
}

.analytics__label {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

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

/* Alerts */
.alerts {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    z-index: 1000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    max-width: 400px;
}

.alert {
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    box-shadow: 0 4px 12px var(--shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
    animation: slideIn 0.3s ease-out;
}

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

.alert--warning {
    background-color: var(--warning);
    color: var(--text-primary);
}

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

.alert__close {
    background: none;
    border: none;
    color: inherit;
    font-size: var(--font-size-lg);
    cursor: pointer;
    padding: 0;
    margin-left: var(--spacing-sm);
}

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

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1100;
    padding: var(--spacing-lg);
}

.modal.show {
    display: flex;
}

.modal__content {
    background-color: var(--bg-primary);
    border-radius: var(--radius-lg);
    box-shadow: 0 8px 32px var(--shadow);
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
}

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

.modal__title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
}

.modal__close {
    background: none;
    border: none;
    font-size: var(--font-size-2xl);
    cursor: pointer;
    color: var(--text-secondary);
    padding: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.modal__close:hover {
    background-color: var(--bg-tertiary);
}

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

.modal__footer {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-sm);
}

/* Footer */
.footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border);
    margin-top: auto;
}

.footer__container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    text-align: center;
}

.footer__text {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

/* Responsive Design */
@media (min-width: 768px) {
    .form__row {
        grid-template-columns: 1fr 1fr;
    }
    
    .form__group--submit {
        grid-column: span 2;
        justify-content: flex-end;
    }
    
    .filters__controls {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .goal-input {
        max-width: 400px;
    }
}

@media (min-width: 1024px) {
    .main {
        padding: var(--spacing-2xl);
    }
    
    .summary__container {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 767px) {
    .header__title {
        font-size: var(--font-size-xl);
    }
    
    .main {
        padding: var(--spacing-lg) var(--spacing-md);
    }
    
    .form-container,
    .filters__container,
    .goals__container,
    .transactions__container,
    .charts__container {
        padding: var(--spacing-md);
    }
    
    .transaction-item {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    .transaction__actions {
        align-self: flex-end;
    }
    
    .charts__grid {
        grid-template-columns: 1fr;
    }
    
    .alerts {
        left: var(--spacing-sm);
        right: var(--spacing-sm);
        max-width: none;
    }
    
    .modal {
        padding: var(--spacing-sm);
    }
    
    .transactions__header {
        flex-direction: column;
        align-items: flex-start;
    }
}

/* Custom Scrollbar */
.transactions__list::-webkit-scrollbar {
    width: 6px;
}

.transactions__list::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
}

.transactions__list::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: var(--radius-sm);
}

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

/* Loading State */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin: -10px 0 0 -10px;
    border: 2px solid var(--primary);
    border-radius: 50%;
    border-top-color: transparent;
    animation: spin 1s linear infinite;
}

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

/* Accessibility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Focus styles for better accessibility */
.btn:focus,
.form__input:focus,
.form__select:focus {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --border: #000000;
        --shadow: rgba(0, 0, 0, 0.5);
    }
    
    [data-theme="dark"] {
        --border: #ffffff;
        --shadow: rgba(255, 255, 255, 0.3);
    }
}

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