JSFiddle - React, Tailwind, and code Playground
by gotoworks510
HTML
<div class="box">こんな感じの縫い目線みたいなボックス作ったり</div>
CSS
.box{
margin:40px;
height:200px;
position: relative;
background:#e9e9e9;
padding:40px;
}
.box:before{
content: '';
z-index: 1;
position: absolute;
border: 1px dashed #bbb;
top: 7px;
bottom: 7px;
left: 7px;
right: 7px;
-moz-box-shadow: 0 0 0 1px #eee;
-webkit-box-shadow: 0 0 0 1px #eee;
box-shadow: 0 0 0 1px #eee;
}