1. 取消拖动调整大小
/*css2.0*/
textarea {width: 400px;max-width: 400px;height: 400px;max-height: 400px;}
/*css3.0*/
texearea {resize: none;}
2. 聚焦时边框颜色不变
input {outline: none;}
textarea {outline: none;}
3.限制input输入字数
<input type="tel" name="authCode" maxlength="6" placeholder="6位数字"/>