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

:root {
  --primary-color: #4f46e5;
  --primary-hover: #4338ca;
  --secondary-color: #6b7280;
  --success-color: #10b981;
  --danger-color: #ef4444;
  --warning-color: #f59e0b;
  --bg-color: #f9fafb;
  --card-bg: #ffffff;
  --text-primary: #111827;
  --text-secondary: #6b7280;
  --border-color: #e5e7eb;
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1),
    0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
  padding: 20px;
}

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

header {
  text-align: center;
  margin-bottom: 40px;
  padding: 30px 0;
}

header h1 {
  font-size: 2.5rem;
  color: var(--primary-color);
  margin-bottom: 10px;
}

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

section {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 30px;
  margin-bottom: 30px;
  box-shadow: var(--shadow-md);
}

section h2 {
  font-size: 1.5rem;
  margin-bottom: 20px;
  color: var(--text-primary);
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 10px;
}

/* Form Styles */
.expense-form-section {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.expense-form-section h2 {
  color: white;
  border-bottom-color: rgba(255, 255, 255, 0.3);
}

#expenseForm {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 15px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.form-group label {
  font-weight: 600;
  font-size: 0.9rem;
}

.form-group input,
.form-group select {
  padding: 12px;
  border: 2px solid var(--border-color);
  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-color);
}

.btn {
  padding: 12px 24px;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
}

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

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

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

.btn-danger {
  background-color: var(--danger-color);
  color: white;
  padding: 6px 12px;
  font-size: 0.875rem;
}

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

.btn-edit {
  background-color: var(--warning-color);
  color: white;
  padding: 6px 12px;
  font-size: 0.875rem;
  margin-right: 5px;
}

.btn-edit:hover {
  background-color: #d97706;
}

/* Analytics Section */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin-bottom: 30px;
}

.stat-card {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  padding: 25px;
  border-radius: 12px;
  color: white;
  text-align: center;
  box-shadow: var(--shadow-md);
}

.stat-label {
  font-size: 0.9rem;
  opacity: 0.9;
  margin-bottom: 10px;
}

.stat-value {
  font-size: 2rem;
  font-weight: bold;
}

.charts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.chart-container {
  background: var(--bg-color);
  padding: 20px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

.chart-container h3 {
  font-size: 1.1rem;
  margin-bottom: 15px;
  color: var(--text-primary);
  text-align: center;
}

.chart-container canvas {
  max-height: 300px;
}

/* Expenses Table */
.filters {
  display: flex;
  flex-wrap: wrap;
  gap: 15px;
  margin-bottom: 20px;
  padding: 15px;
  background: var(--bg-color);
  border-radius: 8px;
  align-items: end;
}

.filter-group {
  display: flex;
  flex-direction: column;
  gap: 5px;
  flex: 1;
  min-width: 150px;
}

.filter-group label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.filter-group input,
.filter-group select {
  padding: 8px;
  border: 2px solid var(--border-color);
  border-radius: 6px;
  font-size: 0.9rem;
}

.table-container {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 10px;
}

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

th {
  padding: 15px;
  text-align: left;
  font-weight: 600;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

td {
  padding: 15px;
  border-bottom: 1px solid var(--border-color);
}

tbody tr:hover {
  background-color: var(--bg-color);
}

.empty-message {
  text-align: center;
  color: var(--text-secondary);
  font-style: italic;
  padding: 40px !important;
}

.category-badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: capitalize;
}

.category-fuel {
  background-color: #fef3c7;
  color: #92400e;
}

.category-food {
  background-color: #d1fae5;
  color: #065f46;
}

.category-travel {
  background-color: #dbeafe;
  color: #1e40af;
}

.category-utilities {
  background-color: #e9d5ff;
  color: #6b21a8;
}

.category-entertainment {
  background-color: #fce7f3;
  color: #9f1239;
}

.category-shopping {
  background-color: #fed7aa;
  color: #9a3412;
}

.category-other {
  background-color: #e5e7eb;
  color: #374151;
}

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

/* Modal Styles */
.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
}

.modal-content {
  background-color: var(--card-bg);
  margin: 10% auto;
  padding: 30px;
  border-radius: 12px;
  width: 90%;
  max-width: 500px;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  position: relative;
}

.close {
  color: var(--text-secondary);
  float: right;
  font-size: 28px;
  font-weight: bold;
  cursor: pointer;
  position: absolute;
  right: 20px;
  top: 20px;
}

.close:hover {
  color: var(--text-primary);
}

.modal-content h2 {
  margin-bottom: 20px;
  margin-top: 10px;
}

/* Responsive Design */
@media (max-width: 768px) {
  body {
    padding: 10px;
  }

  header h1 {
    font-size: 2rem;
  }

  section {
    padding: 20px;
  }

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

  .stats-grid {
    grid-template-columns: 1fr;
  }

  .charts-grid {
    grid-template-columns: 1fr;
  }

  .filters {
    flex-direction: column;
  }

  .filter-group {
    width: 100%;
  }

  table {
    font-size: 0.875rem;
  }

  th,
  td {
    padding: 10px;
  }
}