Kích 100% ô nhâp
<!DOCTYPE html>
<html>
<head>
<style>
input {
width: 100%;
}
</style>
</head>
<body>
<h2>A full-width input field</h2>
<form>
<label for="fname">First Name</label>
<input type="text" id="fname" name="fname">
</form>
</body>
</html>
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