导航栏

<div class="daohang"><div class="ig" id="qx"><img id="" class="app-map-btn app-tap" src="res/im/tq.png"/><span>气象</span></div><div class="ig" id="jt"><img id="" class="app-map-btn app-tap" src="res/im/jt.png"/><span>交通</span></div><div class="ig" id="zhuye"><img id="" class="app-map-btn app-tap" src="res/im/zhuye.png"/><span>主页</span></div><div class="ig" id="ny"><img id="" class="app-map-btn app-tap" src="res/im/ny.png"/><span>农业</span></div><div class="ig" id="ly"><img id="" class="app-map-btn app-tap" src="res/im/ly.png"/><span>旅游</span></div>
</div>

div的样式

 .ig {display: table;float: left;width: 20%;    //将5张图片并排 排列text-align: center;line-height: 27px;color: blue;
}

div中图片的样式

.ig img {margin: auto;		// 主要靠这个width: 53px;height: 53px;
}

结果