CSS定位与小三角效果-优快云博客

做的过程中认识的到问题如果是设置postion值后 left是以父级的左上角定位，而right是以父级的右上角定位。关于小三角号，是利用了一个小方块然后让其旋转45度后，然后把左边和下边的边框去掉（小方块同时设置背景白色，z-index也要设置的比右边的大方框要高，因为要把大方框的一部分右边框遮住。）

css代码

* {
    margin: 0;
    padding: 0;
}
.container-info {
    position: relative;
    list-style: none;
    width: 42px;
    height: 164px;
}
.container{
    width: 42px;
    height: 164px;
    position: fixed;
    bottom: 70px;
    right: 10px;
    background-color: aqua;
}
.container li {
    width: 40px;
    height: 40px;
    padding:0;
}
.container-li1 , .container-li2 , .container-li4 ,.container-li3{
    border: 1px solid red;
}
.container-li2 , .container-li4 ,.container-li3 {
    margin-top: -1px;
}
.container-li3 {
    background-color: gray;
}
.container .i1 {
    width: 40px;
    height: 40px;
    display: inline-block;
    background-image: url(./ico-tphsop-index.png);
    background-position: -235px 0;
 
}
.container .i2 {
    width: 40px;
    height: 40px;
    display: inline-block;
    background-image: url(./ico-tphsop-index.png);
    background-position: -275px 0;
  
}
.container .i3 {
    width: 40px;
    height: 40px;
    display: inline-block;
    background-image: url(./ico-tphsop-index.png);
    background-position: -275px -40px;
    
}
.container .container-li3-inner {
    width: 40px;
    height: 20px;
    text-align: center;
    line-height: 20px;
    font-weight: 700;
    color: #fff;
}
.container .container-li3-hidden {
    position: absolute;
    right: 57px;
    top: 0;
    width: 100px;
    padding: 0 5px;
    height: 167px;
    /* background-color: green; */
    border: 1px solid gray;
}
.container-li3-triangle {
    display: block;
    width: 20px;
    height: 20px;
    position: absolute;
    right: 46px;
    top: 90.5px;
    background-color: white;
    transform: rotate(45deg);
    border: 1px solid grey;
    z-index: 1;
    border-left-color: white;
    border-bottom-color: white;
}
.container-li3-hidden img{
    width: 100px;
    height: 100px;
}
.container-li3-hidden-text {
   text-align: center;
    font-size: 14px;
}
.hidden {
    display: none;
}
.container-li3:hover .hidden {
    display: block;
}

html代码

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="css.css">
</head>
<body>
    <div class="container">
        <ul class="container-info">
            <li class="container-li1"><i class="i1"></i>
            </li>
            <li class="container-li2"><i class="i2"></i></li>
            <li class="container-li3">
                <div class="container-li3-text">
                    <div class="container-li3-inner">手机</div>
                    <div class="container-li3-inner">商城</div>
                </div>
                <div class="hidden">
                    <span class="container-li3-triangle"></span>
                    <div class="container-li3-hidden">
                        <img src=".\qrcode.png" alt="">
                        <div class="container-li3-hidden-text">扫码下载手机</div>
                        <div class="container-li3-hidden-text">商城随时随地</div>
                        <div class="container-li3-hidden-text">享受购物优惠</div>
                    </div>
                </div>    
            </li>
            <li class="container-li4"><i class="i3"></i></li>
        </ul>
    </div>
    
</body>
</html>

运行效果