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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  padding: 20px;
}

.container {
  max-width: 900px;
  margin: 0 auto;
}

h1 {
  text-align: center;
  color: white;
  font-size: 2rem;
  margin-bottom: 30px;
  text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.summary {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 15px;
  margin-bottom: 25px;
}

.summary-card {
  background: white;
  border-radius: 12px;
  padding: 20px;
  text-align: center;
  box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.summary-card h3 {
  font-size: 0.85rem;
  color: #666;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 8px;
}

.summary-card .amount {
  font-size: 1.6rem;
  font-weight: 700;
}

.income .amount { color: #2ecc71; }
.expense .amount { color: #e74c3c; }
.balance .amount { color: #3498db; }

.card {
  background: white;
  border-radius: 12px;
  padding: 25px;
  margin-bottom: 20px;
  box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.card-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: #333;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 2px solid #f0f0f0;
}

.form-group {
  margin-bottom: 15px;
}

.form-group label {
  display: block;
  font-size: 0.9rem;
  color: #555;
  margin-bottom: 6px;
  font-weight: 500;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 10px 14px;
  border: 2px solid #e0e0e0;
  border-radius: 8px;
  font-size: 0.95rem;
  transition: border-color 0.3s;
  outline: none;
}

.form-group input:focus,
.form-group select:focus {
  border-color: #667eea;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 15px;
}

.btn-add {
  width: 100%;
  padding: 12px;
  background: linear-gradient(135deg, #667eea, #764ba2);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  margin-top: 10px;
  transition: opacity 0.3s;
}

.btn-add:hover {
  opacity: 0.9;
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 15px;
  padding-bottom: 10px;
  border-bottom: 2px solid #f0f0f0;
}

.btn-clear {
  padding: 6px 14px;
  background: #ff6b6b;
  color: white;
  border: none;
  border-radius: 6px;
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 0.3s;
}

.btn-clear:hover {
  background: #e74c3c;
}

.transaction-list {
  list-style: none;
  max-height: 350px;
  overflow-y: auto;
}

.transaction-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 15px;
  border-radius: 8px;
  margin-bottom: 8px;
  background: #f8f9fa;
  border-left: 4px solid transparent;
}

.transaction-item.income {
  border-left-color: #2ecc71;
}

.transaction-item.expense {
  border-left-color: #e74c3c;
}

.transaction-item .desc {
  font-weight: 500;
  color: #333;
  font-size: 0.95rem;
}

.transaction-item .date {
  font-size: 0.8rem;
  color: #999;
  margin-top: 2px;
}

.transaction-item .amount {
  font-weight: 700;
  font-size: 1rem;
}

.transaction-item.income .amount { color: #2ecc71; }
.transaction-item.expense .amount { color: #e74c3c; }

.btn-delete {
  background: none;
  border: none;
  color: #ccc;
  cursor: pointer;
  font-size: 1.1rem;
  margin-left: 10px;
  transition: color 0.2s;
}

.btn-delete:hover {
  color: #e74c3c;
}

.empty-state {
  text-align: center;
  color: #aaa;
  padding: 30px;
  font-style: italic;
}

@media (max-width: 600px) {
  .summary {
    grid-template-columns: 1fr;
  }
  .form-row {
    grid-template-columns: 1fr;
  }
}