```html

ta charset="UTF8">

body { fontfamily: Arial, sansserif; }

.calculator { width: 300px; margin: 0 auto; padding: 20px; border: 1px solid #ccc; borderradius: 5px; }

input, button { width: 100%; padding: 10px; margintop: 5px; }

button { backgroundcolor: #007BFF; color: white; border: none; cursor: pointer; }

button:hover { backgroundcolor: #0056b3; }

#result { margintop: 20px; fontsize: 18px; }

cript>

function calculate() {

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

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

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

if (isNaN(loanAmount) || isNaN(interestRate) || isNaN(loanTerm)) {

document.getElementById('result').innerHTML = "请输入有效的数值。";

return;

}

const totalInterest = loanAmount * interestRate * loanTerm;

document.getElementById('result').innerHTML = `总利息为：${totalInterest.toFixed(2)}元`;

}

cript>

```

这段HTML代码创建了一个简单的购房利息计算器。用户可以输入贷款金额、年利率和贷款期限，然后点击“计算利息”按钮来计算总利息。计算结果会显示在页面上。这个计算器使用了基本的Javascript来处理计算逻辑，确保用户输入的数据是有效的，并计算出总利息。