<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>border</title>
<style>
.test {
width: 200px;
height: 200px;
border: 1px solid #eee;
margin: auto;
text-align: center;
}
.in {
border: none;
border-bottom: 1px solid red;
}
</style>
</head>
<body>
<div class="test">
账户:
<input type="text" class="in">
</div>
</body>
</html>