body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  background-color: #f2f2f2;
}

main {
  display: flex;
  flex-wrap: wrap;
  padding: 20px;
}

section {
  background: #fff;
  padding: 15px;
  margin: 10px;
  border-radius: 5px;
  box-shadow: 0 0 5px rgba(0, 0, 0, 0.1);
}

#expense-form-section,
#filter-section {
  flex: 1 1 300px;
}

#expense-list-section {
  flex: 2 1 500px;
}

.form-group {
  margin-bottom: 10px;
}

.form-group label {
  display: block;
  margin-bottom: 5px;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 8px;
  box-sizing: border-box;
}

table {
  width: 100%;
  border-collapse: collapse;
}

table,
th,
td {
  border: 1px solid #ccc;
}

th,
td {
  padding: 10px;
  text-align: left;
}

tr:nth-child(even) {
  background-color: #f9f9f9;
}

button {
  padding: 10px 15px;
  border: none;
  background-color: #52b929;
  color: #fff;
  border-radius: 3px;
  cursor: pointer;
  margin: 5px 2px;
}

button:hover {
  background-color: #52b929;
}

td[data-category="Food"] {
  background-color: #ffe6e6;
}

td[data-category="Transport"] {
  background-color: #e6f2ff;
}

td[data-category="Entertainment"] {
  background-color: #e6ffe6;
}

td[data-category="Other"] {
  background-color: #fff0e6;
}

@media (max-width: 768px) {
  main {
    flex-direction: column;
  }

  #expense-form-section,
  #filter-section,
  #expense-list-section {
    flex: 1 1 100%;
  }
}