```html

ta charset="UTF8">

body { fontfamily: Arial, sansserif; padding: 20px; }

.calculator { width: 400px; margin: 0 auto; }

input, select, button { margintop: 10px; }

button { backgroundcolor: #007BFF; color: white; border: none; padding: 10px 20px; cursor: pointer; }

button:hover { backgroundcolor: #0056b3; }

#result { margintop: 20px; fontweight: bold; }

在线购车计算器

cript>

function calculate() {

const price = parseFloat(document.getElementById('price').value);

const downPaymentRate = parseFloat(document.getElementById('downPayment').value) / 100;

const loanTerm = parseInt(document.getElementById('loanTerm').value);

const interestRate = parseFloat(document.getElementById('interestRate').value) / 100;

const downPayment = price * downPaymentRate;

const loanAmount = price downPayment;

const monthlyInterestRate = interestRate / 12;

const totalMonths = loanTerm * 12;

const monthlyPayment = (loanAmount * monthlyInterestRate) / (1 Math.pow(1 monthlyInterestRate, totalMonths));

const totalPayment = monthlyPayment * totalMonths;

document.getElementById('result').innerHTML = `

首付金额：${downPayment.toFixed(2)}元

每月还款：${monthlyPayment.toFixed(2)}元

总还款额：${totalPayment.toFixed(2)}元

`;

}

cript>

```

这个HTML文档实现了一个简单的在线购车计算器。用户可以输入车辆价格、首付比例、贷款期限和年利率，然后点击“计算”按钮，计算器会显示首付金额、每月还款额和总还款额。这个计算器使用了基本的Javascript来处理计算逻辑，并使用HTML和CSS来构建用户界面。