css如何清除form表单样式的示例

::-webkit-input-placeholder{color: #333;}
:-moz-placeholder{color: #333;}
:-moz-placeholder{color: #333;} 
:-ms-input-placeholder{color: #333;}

input::-webkit-outer-spin-button,input
::-webkit-inner-spin-button{-webkit-appearance: none !important;}input[type="number"]{-moz-appearance:textfield;}

direction: rtl;

-webkit-appearance: none;

resize:none;

<p class="ta_box">
 <textarea class="ta"></textarea></p>

.ta_box{
 width: 400px;
 height: auto;
 overflow: hidden;
 border: 1px solid #999;
 box-sizing: border-box;
}.ta{
 min-height: 30px;
 outline: none;
 resize: none;
 width: 500px;
 box-sizing: border-box;
 vertical-align: top;
 border: none;
}

$.fn.autoHeight = function () { function autoHeight (elem) {
 elem.style.height = 'auto';
 elem.scrollTop = 0; //防抖动
 elem.style.height = elem.scrollHeight + 'px';
 } this.each(function () {
 autoHeight(this);
 $(this).on('keyup',function () {
 autoHeight(this);
 });
 });
}
$('textarea').autoHeight();