body{
    margin: 0;
    font-size: 16px;
}
.flex{
    display: flex;
    flex-direction: row;
}
.flex-row{
    display: flex;
    flex-direction: row;
    align-items: center;
}
.flex-row-default{
    display: flex;
    flex-direction: row;
}
.flex-column{
    display: flex;
    flex-direction: column;
    align-items: center;
}
.flex-column-default{
    display: flex;
    flex-direction: column;
}
.flex-center{
    justify-content: center;
}




body .box{
    margin: 0 auto;
    height: 100%;
    position: relative;
}
body .box::after{
    content: "";
    height: 300px;
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background-image: url("../img/bg.png");
    background-size: cover;
    z-index: 0;
}
.left,.right{
    width: 35%;
    z-index: 10;
}

.left img{
    width: 100%;
}
.left {
    margin-right: 50px;
}
.right h1{
    color: #F56C6C;
    font-weight: bold;
    margin: 0;
    font-size: 6em;
}
.right h2{
    color: #598bb5;
    font-weight: bold;
    font-size: 2.5em;
    margin-top: 0;
}
.right span{
    font-size: 1.2em;
    margin-bottom: 20px;
    color: #606266;
}
.btn{
    height: 40px;
    width: 100px;
    color: white;
    border: none;
    background: #409EFF;
    border-radius: 5px;
    font-size: 15px;
    cursor: pointer;
}
.btn:focus{
    outline: none;
    border: none;
}
.btn:active{
    background: #2391ff;
}
 
@media (max-width: 768px) {
    /** 窗口宽度小于768像素的样式 **/
    body .box::after{
        height: 100px !important;
    }
    .left,.right{
        width: 85%;
        z-index: 10;
        margin: 0;
    }
    .box{
        flex-direction: column;
    }
    .right{
        align-items: center;
    }
    .right h1{
        font-weight: bold;
        font-size: 4em;
    }
    .right h2{
        font-size: 1.5em;
    }
    .right span{
        font-size: 1em;
    }
    .btn{
        width: 100%;
    }
}