点击运行
<!DOCTYPE html> <html> <head> <style> input[type=text] { width: 100%; padding: 12px 20px; margin: 8px 0; box-sizing: border-box; border: none; border-bottom: 2px solid red; } </style> </head> <body> <p>只有下边框的文本字段：</p> <form> <label for="fname">First Name</label> <input type="text" id="fname" name="fname"> <label for="lname">Last Name</label> <input type="text" id="lname" name="lname"> </form> </body> </html>
运行结果
