* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

:root {
    --primary: #4361ee;
    --secondary: #3a0ca3;
    --success: #4cc9f0;
    --danger: #f72585;
    --warning: #f8961e;
    --light: #f8f9fa;
    --dark: #212529;
    --gray: #6c757d;
    --income: #2ecc71;
    --expense: #e74c3c;
    --card-bg: #ffffff;
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    --border-radius: 12px;
}

body {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: 100vh;
    padding: 20px;
    color: var(--dark);
}

.container {
    max-width: 1400px;
    margin: 0 auto;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 30px;
    padding: 25px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* Summary Cards */
.summary-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.card {
    background: var(--card-bg);
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    transition: transform 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
}

.card h3 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: var(--gray);
    display: flex;
    align-items: center;
    gap: 10px;
}

.amount {
    font-size: 2.2rem;
    font-weight: bold;
}

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

.total-income .amount {
    color: var(--income);
}

.total-expense .amount {
    color: var(--expense);
}

/* Main Content Layout */
.main-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 30px;
}

@media (max-width: 1100px) {
    .main-content {
        grid-template-columns: 1fr;
    }
}

/* Form Container */
.form-container, .chart-container, .transactions-container, .monthly-summary {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 25px;
    margin-bottom: 25px;
}

.form-container h2, .chart-container h2, .transactions-container h2, .monthly-summary h2 {
    margin-bottom: 20px;
    color: var(--primary);
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
}

/* Form Styles */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--dark);
    display: flex;
    align-items: center;
    gap: 8px;
}

.form-group input, .form-group select {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-group input:focus, .form-group select:focus {
    outline: none;
    border-color: var(--primary);
}

.radio-group {
    display: flex;
    gap: 20px;
    margin-top: 10px;
}

.radio-label {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    border: 2px solid #e0e0e0;
}

.radio-label input {
    display: none;
}

.radio-label.income-radio span {
    color: var(--income);
}

.radio-label.expense-radio span {
    color: var(--expense);
}

.radio-label input:checked + span {
    font-weight: bold;
}

.radio-label.income-radio input:checked ~ span {
    color: white;
}

.radio-label.expense-radio input:checked ~ span {
    color: white;
}

.radio-label.income-radio input:checked {
    background-color: var(--income);
}

.radio-label.expense-radio input:checked {
    background-color: var(--expense);
}

.radio-label input:checked {
    background-color: var(--primary);
    border-color: var(--primary);
}

.radio-label.income-radio input:checked {
    background-color: var(--income);
    border-color: var(--income);
}

.radio-label.expense-radio input:checked {
    background-color: var(--expense);
    border-color: var(--expense);
}

.radio-label.income-radio input:checked {
    background-color: var(--income);
    border-color: var(--income);
}

.radio-label.income-radio input:checked ~ span {
    color: white;
}

.radio-label.expense-radio input:checked {
    background-color: var(--expense);
    border-color: var(--expense);
}

.radio-label.expense-radio input:checked ~ span {
    color: white;
}

.btn-add {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    transition: transform 0.3s;
}

.btn-add:hover {
    transform: scale(1.02);
}

/* Chart Container */
.chart-container {
    height: 400px;
}

#categoryChart {
    width: 100% !important;
    height: 300px !important;
}

/* Transactions */
.transactions-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 20px;
}

.filter-controls {
    display: flex;
    gap: 10px;
}

.filter-controls select {
    padding: 8px 15px;
    border: 2px solid #e0e0e0;
    border-radius: 6px;
    background: white;
}

.transactions-list {
    max-height: 400px;
    overflow-y: auto;
    padding-right: 10px;
}

.transaction-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px;
    margin-bottom: 10px;
    background: #f8f9fa;
    border-radius: 8px;
    border-left: 5px solid;
    transition: all 0.3s;
}

.transaction-item:hover {
    background: #e9ecef;
    transform: translateX(5px);
}

.transaction-item.income {
    border-left-color: var(--income);
}

.transaction-item.expense {
    border-left-color: var(--expense);
}

.transaction-info {
    flex: 1;
}

.transaction-description {
    font-weight: 600;
    margin-bottom: 5px;
}

.transaction-meta {
    display: flex;
    gap: 15px;
    font-size: 0.9rem;
    color: var(--gray);
}

.transaction-category {
    padding: 3px 10px;
    border-radius: 20px;
    background: #e0e0e0;
    font-size: 0.8rem;
}

.transaction-amount {
    font-weight: bold;
    font-size: 1.2rem;
}

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

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

.delete-btn {
    background: none;
    border: none;
    color: var(--danger);
    cursor: pointer;
    font-size: 1.2rem;
    margin-left: 15px;
    transition: transform 0.3s;
}

.delete-btn:hover {
    transform: scale(1.2);
}

.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--gray);
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 15px;
    color: #dee2e6;
}

.transactions-summary {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid #e0e0e0;
}

.btn-clear {
    padding: 8px 20px;
    background: var(--danger);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: background 0.3s;
}

.btn-clear:hover {
    background: #d1144a;
}

/* Monthly Summary */
.monthly-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.stat {
    text-align: center;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 8px;
}

.stat-label {
    display: block;
    font-size: 0.9rem;
    color: var(--gray);
    margin-bottom: 8px;
}

.stat-value {
    font-size: 1.8rem;
    font-weight: bold;
    display: block;
}

.income-stat {
    color: var(--income);
}

.expense-stat {
    color: var(--expense);
}

.net-stat {
    color: var(--primary);
}

/* Footer */
footer {
    text-align: center;
    padding: 20px;
    color: var(--gray);
    font-size: 0.9rem;
    border-top: 1px solid #e0e0e0;
    margin-top: 20px;
}

/* Responsive */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    .summary-cards {
        grid-template-columns: 1fr;
    }
    
    .monthly-stats {
        grid-template-columns: 1fr;
    }
    
    .transactions-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .filter-controls {
        width: 100%;
    }
    
    .filter-controls select {
        flex: 1;
    }
}