:root {
    /* Color Palette */
    --primary-hue: 260;
    --success-hue: 145;
    --danger-hue: 0;
    
    --bg-primary: hsl(240, 15%, 8%);
    --bg-secondary: hsl(240, 12%, 12%);
    --bg-tertiary: hsl(240, 10%, 16%);
    
    --text-primary: hsl(0, 0%, 95%);
    --text-secondary: hsl(0, 0%, 70%);
    --text-muted: hsl(0, 0%, 50%);
    
    --accent-primary: hsl(var(--primary-hue), 85%, 65%);
    --accent-secondary: hsl(var(--primary-hue), 75%, 55%);
    --accent-gradient: linear-gradient(135deg, hsl(var(--primary-hue), 85%, 65%), hsl(calc(var(--primary-hue) + 30), 80%, 60%));
    
    --success: hsl(var(--success-hue), 70%, 55%);
    --success-light: hsl(var(--success-hue), 70%, 65%);
    --success-gradient: linear-gradient(135deg, hsl(var(--success-hue), 70%, 55%), hsl(var(--success-hue), 65%, 65%));
    
    --danger: hsl(var(--danger-hue), 75%, 60%);
    --danger-light: hsl(var(--danger-hue), 75%, 70%);
    --danger-gradient: linear-gradient(135deg, hsl(var(--danger-hue), 75%, 60%), hsl(var(--danger-hue), 70%, 70%));
    
    /* Glassmorphism */
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.5rem;
    --radius-md: 1rem;
    --radius-lg: 1.5rem;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

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

body {
    font-family: var(--font-family);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    background-image: 
        radial-gradient(circle at 20% 20%, hsla(var(--primary-hue), 85%, 65%, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, hsla(var(--success-hue), 70%, 55%, 0.1) 0%, transparent 50%);
    background-attachment: fixed;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    animation: fadeIn 0.6s ease;
}

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

/* Header */
.header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    animation: slideDown 0.6s ease;
}

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

.header-title {
    font-size: 3rem;
    font-weight: 700;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-xs);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.icon {
    font-size: 3rem;
    filter: drop-shadow(0 0 20px rgba(255, 255, 255, 0.3));
}

.header-subtitle {
    color: var(--text-secondary);
    font-size: 1.1rem;
    font-weight: 300;
}

/* Summary Cards */
.summary-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.summary-card {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    box-shadow: var(--glass-shadow);
    transition: all var(--transition-normal);
    animation: scaleIn 0.5s ease backwards;
}

.summary-card:nth-child(1) { animation-delay: 0.1s; }
.summary-card:nth-child(2) { animation-delay: 0.2s; }
.summary-card:nth-child(3) { animation-delay: 0.3s; }

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

.summary-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
    border-color: rgba(255, 255, 255, 0.2);
}

.card-icon {
    font-size: 2.5rem;
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.05);
}

.income-card .card-icon {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.2), rgba(5, 150, 105, 0.1));
}

.expense-card .card-icon {
    background: linear-gradient(135deg, rgba(239, 68, 68, 0.2), rgba(220, 38, 38, 0.1));
}

.balance-card .card-icon {
    background: linear-gradient(135deg, rgba(139, 92, 246, 0.2), rgba(124, 58, 237, 0.1));
}

.card-content {
    flex: 1;
}

.card-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
    font-weight: 500;
}

.card-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
}

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

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

.balance-card .card-value {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Card Component */
.card {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--glass-shadow);
    animation: fadeIn 0.6s ease backwards;
}

.section-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

/* Main Grid */
.main-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

/* Transaction Form */
.transaction-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.form-group label {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: 0.75rem 1rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: var(--font-family);
    font-size: 1rem;
    transition: all var(--transition-fast);
}

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

.form-group select option {
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding: 0.5rem;
}

.form-group select optgroup {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    font-weight: 600;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
    background: rgba(255, 255, 255, 0.08);
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.1);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--text-muted);
}

/* Buttons */
.btn {
    padding: 0.875rem 1.5rem;
    border: none;
    border-radius: var(--radius-sm);
    font-family: var(--font-family);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(139, 92, 246, 0.4);
}

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

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
}

.btn-icon {
    font-size: 1.2rem;
}

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

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

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

.filters {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    align-items: flex-end;
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
}

.filter-group {
    flex: 1;
    min-width: 150px;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.filter-group label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.filter-group input,
.filter-group select {
    padding: 0.625rem 0.875rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: var(--font-family);
    font-size: 0.9rem;
    transition: all var(--transition-fast);
}

.filter-group input:focus,
.filter-group select:focus {
    outline: none;
    border-color: var(--accent-primary);
    background: rgba(255, 255, 255, 0.08);
}

/* Transactions List */
.transactions-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    max-height: 600px;
    overflow-y: auto;
    padding-right: var(--spacing-xs);
}

.transactions-list::-webkit-scrollbar {
    width: 8px;
}

.transactions-list::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-sm);
}

.transactions-list::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-sm);
}

.transactions-list::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.15);
}

.transaction-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md);
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    animation: slideIn 0.3s ease;
}

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

.transaction-item:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.1);
    transform: translateX(5px);
}

.transaction-info {
    flex: 1;
}

.transaction-description {
    font-weight: 600;
    font-size: 1.05rem;
    margin-bottom: 0.25rem;
}

.transaction-meta {
    display: flex;
    gap: var(--spacing-md);
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.transaction-category {
    padding: 0.25rem 0.75rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 1rem;
    font-size: 0.8rem;
}

.transaction-notes {
    margin-top: 0.5rem;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-style: italic;
    padding: 0.5rem;
    background: rgba(255, 255, 255, 0.03);
    border-radius: var(--radius-sm);
    border-left: 2px solid rgba(139, 92, 246, 0.3);
}

.transaction-amount {
    font-size: 1.25rem;
    font-weight: 700;
    margin-right: var(--spacing-md);
}

.transaction-item.income .transaction-amount {
    color: var(--success-light);
}

.transaction-item.expense .transaction-amount {
    color: var(--danger-light);
}

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

.action-btn {
    padding: 0.5rem 0.75rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    cursor: pointer;
    font-size: 0.85rem;
    transition: all var(--transition-fast);
}

.action-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: scale(1.05);
}

.action-btn.edit:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.action-btn.delete:hover {
    border-color: var(--danger);
    color: var(--danger);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: var(--spacing-xl);
    color: var(--text-secondary);
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-md);
    opacity: 0.5;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.3s ease;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--bg-secondary);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    max-width: 600px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    animation: scaleIn 0.3s ease;
}

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

.modal-header h2 {
    font-size: 1.5rem;
    color: var(--text-primary);
}

.modal-close {
    background: none;
    border: none;
    font-size: 2rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
}

.modal-close:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

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

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

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: var(--spacing-md);
    }
    
    .header-title {
        font-size: 2rem;
    }
    
    .icon {
        font-size: 2rem;
    }
    
    .main-grid {
        grid-template-columns: 1fr;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .filters {
        flex-direction: column;
    }
    
    .filter-group {
        width: 100%;
    }
    
    .charts-container {
        grid-template-columns: 1fr;
    }
    
    .transaction-item {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    .transaction-amount {
        margin-right: 0;
    }
}

@media (max-width: 480px) {
    .header-title {
        font-size: 1.5rem;
        flex-direction: column;
        gap: var(--spacing-xs);
    }
    
    .summary-section {
        grid-template-columns: 1fr;
    }
    
    .card-value {
        font-size: 1.5rem;
    }
}