前端模态对话框：

 

 

 

 

源码可复制粘贴：

        .hide{
            display: none;
        }
        {#shade遮罩层把满屏都遮住 ,fixed是固定的,opacity透明度#}
        .shade{
            position: fixed;
            top: 0;bottom: 0;left: 0;right: 0;
            background: black;
            opacity: 0.6;
            z-index: 100;


        }
        {#add-modal 弹出框 ,fixed是固定的,z-index定位谁在里面#}
        .add-modal{
            position: fixed;
            height: 300px;
            width: 400px;
            top: 200px;
            left: 50%;
            z-index: 101;
            border: 1px solid red;
            background: white;
            margin-left: -200px;
        }

 

</div>
{# 遮罩层 #}
<div class="shade hide" ></div>
{# 弹出添加层 #}
<div class="add-modal hide" ></div>