.worldmap {
    background-image: url(worldmap.jpg);
    background-repeat: no-repeat;
    background-size: 100% 100%;
    /*background-attachment: fixed;*/
    width:100%;
    /*height:400px*/
}

.dot:before {
    content: ' ';
    position: absolute;
    z-index:2;
    left:0;
    top:0;
    width:10px;
    height:10px;
    background-color:#ff4200;
    border-radius:50%;
}

.dot:after {
    content: ' ';
    position: absolute;
    z-index: 1;
    width: 10px;
    height: 10px;
    background-color: #ff4200;
    border-radius: 50%;
    box-shadow: 0 0 10px rgba(0,0,0,.3) inset;
    -webkit-animation-name: ripple ; /*动画属性名，也就是我们前面keyframes定义的动画名*/
    -webkit-animation-duration: 1s ; /*动画持续时间*/
    -webkit-animation-timing-function: ease ;
    /*动画频率，和transition-timing-function是一样的*/
    -webkit-animation-delay: 0s ; /*动画延迟时间*/
    -webkit-animation-iteration-count: infinite ; /*定义循环资料，infinite为无限次*/
    -webkit-animation-direction: normal; /*定义动画方式*/
}


@keyframes ripple{
    0%{
        left: 5px;
        top: 5px;
        opacity:100;
        width: 0;
        height: 0;
    }

    100%{
        left: -20px;
        top: -20px;
        opacity:0;
        width: 50px;
        height: 50px;
    }
}