.container {
  max-width: 500px;
  margin: auto;
  background: #1e1e1e;
  color: #ffffff;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 0 10px rgba(255, 255, 255, 0.05);
  font-family: Arial, sans-serif;
}

.container h2,
.container h3 {
  text-align: center;
}

.container input,
.container button {
  padding: 10px;
  margin: 5px 0;
  width: 100%;
  border: none;
  border-radius: 5px;
  box-sizing: border-box;
}

.container input {
  background: #2c2c2c;
  color: #fff;
}

.container button {
  background-color: #4caf50;
  color: #fff;
  cursor: pointer;
}

.container ul {
  list-style: none;
  padding: 0;
}

.container li {
  background: #2c2c2c;
  margin: 10px 0;
  padding: 10px;
  display: flex;
  justify-content: space-between;
  border-left: 5px solid;
  border-radius: 5px;
}

.container li.income {
  border-color: #4caf50;
}

.container li.expense {
  border-color: #f44336;
}

.container canvas {
  margin-top: 20px;
  max-width: 100%;
}

@media (max-width: 600px) {
  .container {
    padding: 15px;
  }

  .container input,
  .container button {
    font-size: 16px;
  }
}