ul li select

.category_box {width: 30rem; margin-top:5rem;}
.category_box p {margin-bottom: 1rem;}
.category_box .cate_select  { width:100%; position: relative; display: inline-block;}
.category_box .cate_select  a { display:flex; align-items: center; justify-content: space-between; font-size: .9em; padding: 0 2rem; background:rgba(0,0,0,.05); border:0; border-bottom:1px solid var(--black); width: auto; height: 6rem;}
.category_box .cate_select > i{ position:absolute; right:2rem; top:50%;transform:translateY(-50%);}
.category_box .cate_select > i.active{transform: translateY(-50%) rotate(270deg );}
.category_box .cate_select_list{display: none; position: absolute; width: 100%;  background:var(--white);box-shadow: 0px 6px 10px 0px rgba(0,0,0,.2);}
.category_box .cate_select_list.active{display: block}
.category_box .cate_select_list li{padding:1.5rem 2rem; cursor: pointer;}
.category_box .cate_select_list li + li{border-top:none;}
.category_box .cate_select_list li:hover{background:var(--black); color:var(--white);}​

<div class="category_box">
    <p>Category</p>

    <div class="cate_select">
        <a href="javascript:;"><strong>ALL</strong></a>
        <ul class="cate_select_list">
            <li>ALL</li>
            <li>1</li>
            <li>2</li>
            <li>3</li>
        </ul>
    </div>
</div>

	var _select_title = $(".cate_select > a");
	$('<i class="select_icon xi-caret-down-min"></i>').insertAfter(_select_title);

	_select_title.click(function () {
	  $(".cate_select_list").toggleClass("active");
	  $(".select_icon").toggleClass("active");
	});

	$(".cate_select_list > li").on('click', function () {
	  var _li_value = $(this).text();
	  _select_title.text(_li_value);
	  $(".cate_select_list").removeClass("active");
	  $(".select_icon").toggleClass("active");
	});
	$("body").click(function (e) {
	  if($(".cate_select_list").hasClass("active")){
		if(!$(".cate_select").has(e.target).length){
		  $(".cate_select_list").removeClass("active");
		  $(".select_icon").removeClass("active");
		};
	  }
	});