html,body{
    width: 100%;
    height: 100%;
}

* {
    margin: 0;
    padding: 0;
}

.first {
    height: 100%;
    width:100%;
    height: 100%;
    background-image:url(../img/back.png);
}

.header {
    width: 100%;
    display: flex;
    flex-direction: row;
    justify-content: space-between;
}

.logo {
    margin-top: 20px;
    margin-left: 20px;
    background-image:url(../img/logo.png);
    width:240px;
    height: 90px;

}

.text {
    width: 46%;
    height: 150px;
    font-size: 50px;
    display: flex;
    flex-direction: row;
}

.text div {
    width: 50%;
    text-align: center;
    line-height: 142px;
    color: #444444;
    cursor: pointer;
    /* border-bottom:1px solid #000 */
}

.text div:hover {
    background-color: #d9d9da;
}


.center {
    display: flex;
    flex-direction: row;
}
.describe {
    margin-top: 10%;
    margin-left: 12.5%;
    font-size: 3rem;
    font-family: "PingFangSC-Medium","SourceHanSansSC-Medium","Microsoft YaHei";
    font-weight: 500;
    color: #444444;
}

.describe div {
    margin-bottom: 10px;
}

.describe-text3 {
    color: #585858;
}

.describe-pic {
    margin-left: 12.5%;
    margin-top: 10%;
}

.describe-pic-fly {
    background-image:url(../img/fly1.png);
    width:500px;
    height: 250px;
}


.describe-pic-baby {
    background-image:url(../img/back.jpg);
    width:500px;
    height: 250px;
}

.footer {
    width: 100%;
    position: fixed;
    bottom: 10px;
    display: flex;
    justify-content: center;
    flex-direction: row;
    text-align: center;
    font-size: 10px;
}

@media screen and (max-width: 500px) {
    .header {
        flex-direction: column;
    }

    .text {
        margin-left: 10px;
        width: 90%;
        height: 60px;
        font-size: 40px;
        display: flex;
        flex-direction: row;
    }

    .text div {
        width: 50%;
        text-align: center;
        line-height: 50px;
    }

    .center {
        display: flex;
        flex-direction: column;
    }

    .describe {
        margin-left: 3%;
        font-size: 2rem;
    }

    .describe-pic-fly {
        margin-left: -50px;
        background-image:url(../img/fly.png);
        width:400px;
        height: 250px;
    }

    .describe-pic {
        margin-left: 1%;
        margin-top: 10%;
    }
}