手机网页右上角点击下拉导航按钮
1、准备好需要用到的图标。

2、新建html文档。

4、书写css代码。*{ margin:0; padding:0; list-style:none;}#header{background-color: #00a1e9;text-align: center;height: 0.44rem;line-height: 0.44rem;color: #fff;position: relative;}#header span.right{width: 0.44rem;height: 0.44rem;position: absolute;right: 0;top: 0;background: url("img/btn.jpg") no-repeat center center;background-size: 80%;transform:rotate(0deg);-ms-transform:rotate(0deg); /* IE 9 */-moz-transform:rotate(0deg); /* Firefox */-webkit-transform:rotate(0deg); /* Safari 和 Chrome */-o-transform:rotate(0deg);-webkit-transition: all 0.3s linear;-ms-transition: all 0.3s linear;-moz-transition: all 0.3s linear;-o-transition: all 0.3s linear;transition: all 0.3s linear;}#header span.right.on{background: url("img/btn.png") no-repeat center center;background-size: 55%;transform:rotate(135deg);-ms-transform:rotate(135deg); /* IE 9 */-moz-transform:rotate(135deg); /* Firefox */-webkit-transform:rotate(135deg); /* Safari 和 Chrome */-o-transform:rotate(135deg);-webkit-transition: all 0.3s linear;-ms-transition: all 0.3s linear;-moz-transition: all 0.3s linear;-o-transition: all 0.3s linear;transition: all 0.3s linear;}#header h1{font-size: 0.16rem;font-weight: normal;}#header span.left{position:absolute;left:0;top:0;display: block;width: 0.44rem;height: 0.44rem;font-size: 0.14rem;padding-left:0.08rem;}.menu{overflow: hidden;background-color: #00a1e9;width: 100%;position: absolute;left: 0;top: 0.44rem;right: 0;z-index: 9999;height: 0;-webkit-transition: all 0.3s linear;-ms-transition: all 0.3s linear;-moz-transition: all 0.3s linear;-o-transition: all 0.3s linear;transition: all 0.3s linear;}.menu li{width: 100%;text-align: center;border-bottom: 0.01rem solid #0097da;font-size: 0.16rem;height: 0.4rem;line-height: 0.4rem;}.menu li a{color: #fff;display: inline-block;width: 100%;text-align: center; text-decoration:none;}</style>

6、代码整体结构。
