.tracker-box {
  font-family: system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  background: #fff;
  padding: 30px;
  border-radius: 16px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.05);
  max-width: 400px;
  margin: 0 auto;
}
h3 {
  margin-top: 0;
  color: #1f2937;
}
.balance {
  font-size: 1.5rem;
  font-weight: 700;
  color: #2563eb;
  margin-bottom: 20px;
}
.list {
  list-style: none;
  padding: 0;
  margin-bottom: 20px;
  max-height: 200px;
  overflow-y: auto;
}
.list li {
  display: flex;
  justify-content: space-between;
  padding: 10px;
  border-bottom: 1px solid #f3f4f6;
  color: #4b5563;
}
.list li:last-child { border: none; }
.add-form {
  display: flex;
  gap: 10px;
}
input {
  padding: 10px;
  border: 1px solid #d1d5db;
  border-radius: 8px;
  outline: none;
  width: 100%;
}
button {
  background: #10b981;
  color: white;
  border: none;
  padding: 10px 20px;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
}

const list = document.getElementById("expenseList");
const totalEl = document.getElementById("total");
const descInput = document.getElementById("desc");
const amountInput = document.getElementById("amount");
let total = 0;

function addExpense() {
  const desc = descInput.value;
  const amount = parseFloat(amountInput.value);
  
  if (desc === "" || isNaN(amount)) return;
  
  const li = document.createElement("li");
  li.innerHTML = `${desc} <span>$${amount.toFixed(2)}</span>`;
  list.appendChild(li);
  
  total += amount;
  totalEl.innerText = "$" + total.toFixed(2);
  
  descInput.value = "";
  amountInput.value = "";
}