@media (max-width: 768px) {
    html {
        font-size: 5px !important;
    }

    body {
        font-family: Arial, Helvetica, sans-serif;
        margin: 0;
        padding: 0;
        background: #151621;
        background-size: cover;
    }

    header h1 {
        position: relative;
        font-size: 5rem;
        color: #fff;
        text-align: center;
        line-height: 8rem;
        top: -1rem;
        border-bottom: 1px solid rgba(193, 227, 250, 0.36);
    }

    section a {
        text-decoration: none;
        color: #fff;
    }

    .navigation {
        position: relative;
        font-size: 2rem;
        height: 5rem;
        color: #fff;
        text-align: right;
        top: -2rem;
    }

    .navigation .login {
        position: relative;
        right: 2rem;
    }

    .navigation .console {
        position: relative;
        right: 4rem;
    }

    .navigation .iot {
        position: relative;
        right: 6rem;
    }

    .navigation .home {
        position: relative;
        right: 8rem;
    }

    .brief h2 {
        position: relative;
        font-size: 3.5rem;
        color: rgba(196, 250, 250, 0.64);
        line-height: 6rem;
        text-align: center;
        top: -1rem;
    }

    .iot_info {
        position: relative;
        /*background: #a81653;*/
        padding: 0rem 0rem 0rem;
        box-shadow: 0px 0px 10px #b5e1e1;
        border: 1px solid #fff;
        height: 18rem; /**/
        width: 90%;
        margin: 0 auto;
        top: 4rem;
    }

    .iot_info .img {
        position: relative;
        top: 2.5rem; /**/
        left: 5%;
    }

    .iot_info .img img {
        opacity: 0.8;
        width: 26rem; /**/
        height: 13rem; /**/
    }

    .iot_info .h2 {
        position: relative;
        /*background: #92b4f5;*/
        height: 90%;
        width: 50%;
        margin-left: 47%; /**/
        margin-top: -14rem; /**/
    }

    .iot_info .h2 h2 {
        font-size: 2rem;
        color: rgba(247, 252, 252, 0.6);
    }

    .smart_info {
        position: relative;
        padding: 0rem 0rem 0rem;
        box-shadow: 0px 0px 10px #b5e1e1;
        border: 1px solid #fff;
        height: 18rem;
        width: 90%;
        margin: 0 auto;
        top: 6rem;
    }

    .smart_info .img {
        position: relative;
        top: 2.5rem;
        left: 5%;
    }

    .smart_info .img img {
        opacity: 0.8;
        width: 26rem;
        height: 13rem;
    }

    .smart_info .h2 {
        position: relative;
        /*background: #92b4f5;*/
        height: 90%;
        width: 50%;
        margin-left: 47%;
        margin-top: -14rem;
    }

    .smart_info .h2 h2 {
        font-size: 2rem;
        color: rgba(247, 252, 252, 0.6);
    }

    .ai_info {
        position: relative;
        padding: 0rem 0rem 0rem;
        box-shadow: 0px 0px 10px #b5e1e1;
        border: 1px solid #fff;
        height: 18rem;
        width: 90%;
        margin: 0 auto;
        top: 8rem;
    }

    .ai_info .img {
        position: relative;
        top: 2.5rem;
        left: 5%;
    }

    .ai_info .img img {
        opacity: 0.8;
        width: 26rem;
        height: 13rem;
    }

    .ai_info .h2 {
        position: relative;
        /*background: #92b4f5;*/
        height: 90%;
        width: 50%;
        margin-left: 47%;
        margin-top: -14rem;
    }

    .ai_info .h2 h2 {
        font-size: 2rem;
        color: rgba(247, 252, 252, 0.6);
    }

    .footer {
        position: relative;
        background: rgba(12, 13, 14, 0.72);
        height: 16rem;
        width: 100%;
        top: 28rem;
    }

    .footer .info {
        position: absolute;
        width: 90%;
        left: 5%;
        line-height: 1rem;
        padding: 2rem 0 1rem 0;
    }

    .footer .info p {
        font-size: 1.5rem;
        color: rgba(236, 230, 230, 0.85);
    }

    .footer .info a {
        font-size: 1.5rem;
        color: rgba(236, 230, 230, 0.85);
    }
}


@media (min-width: 768px) {
    html {
        font-size: 21px !important;
    }

    body {
        font-family: Arial, Helvetica, sans-serif;
        font-size: 21px; /* 默认字体大小 */
        margin: 0;
        padding: 0;
        background: #151621;
        background-size: cover;
        min-width: 1500px;
    }

    header h1 {
        position: relative;
        font-size: 2.2rem;
        color: #fff;
        text-align: center;
        line-height: 4rem;
        top: -1rem;
        border-bottom: 2px solid rgba(193, 227, 250, 0.36);
    }

    section a {
        text-decoration: none;
        color: #fff;
    }

    .navigation {
        position: relative;
        font-size: 1rem;
        height: 5rem;
        color: #fff;
        text-align: right;
        top: -1.5rem;
    }

    .navigation .login {
        position: relative;
        right: 2rem;
    }

    .navigation .console {
        position: relative;
        right: 4rem;
    }

    .navigation .iot {
        position: relative;
        right: 6rem;
    }

    .navigation .home {
        position: relative;
        right: 8rem;
    }

    .brief h2 {
        position: relative;
        font-size: 2rem;
        color: rgba(196, 250, 250, 0.64);
        line-height: 4rem;
        text-align: center;
        top: -4rem;
    }

    .iot_info {
        position: relative;
        /*background: #a81653;*/
        padding: 0rem 0rem 0rem;
        box-shadow: 0px 0px 10px #b5e1e1;
        border: 1px solid #fff;
        height: 12rem;
        width: 70%;
        margin: 0 auto;
        top: -2rem;
    }

    .iot_info .img {
        position: relative;
        top: 1.35rem;
        left: 5%;
    }

    .iot_info .img img {
        opacity: 0.8;
        width: 19rem;
        height: 9.5rem;
    }

    .iot_info .h2 {
        position: relative;
        /*background: #92b4f5;*/
        height: 90%;
        width: 40%;
        margin-left: 55%;
        margin-top: -10rem;
    }

    .iot_info .h2 h2 {
        font-size: 1.3rem;
        color: rgba(247, 252, 252, 0.6);
    }

    .smart_info {
        position: relative;
        padding: 0rem 0rem 0rem;
        box-shadow: 0px 0px 10px #b5e1e1;
        border: 1px solid #fff;
        height: 12rem;
        width: 70%;
        margin: 0 auto;
        top: -1rem;
    }

    .smart_info .img {
        position: relative;
        top: 1.35rem;
        left: 5%;
    }

    .smart_info .img img {
        opacity: 0.8;
        width: 19rem;
        height: 9.5rem;
    }

    .smart_info .h2 {
        position: relative;
        /*background: #92b4f5;*/
        height: 90%;
        width: 40%;
        margin-left: 55%;
        margin-top: -10rem;
    }

    .smart_info .h2 h2 {
        font-size: 1.3rem;
        color: rgba(247, 252, 252, 0.6);
    }

    .ai_info {
        position: relative;
        padding: 0rem 0rem 0rem;
        box-shadow: 0px 0px 10px #b5e1e1;
        border: 1px solid #fff;
        height: 12rem;
        width: 70%;
        margin: 0 auto;
        top: 0rem;
    }

    .ai_info .img {
        position: relative;
        top: 1.35rem;
        left: 5%;
    }

    .ai_info .img img {
        opacity: 0.8;
        width: 19rem;
        height: 9.5rem;
    }

    .ai_info .h2 {
        position: relative;
        /*background: #92b4f5;*/
        height: 90%;
        width: 40%;
        margin-left: 55%;
        margin-top: -10rem;
    }

    .ai_info .h2 h2 {
        font-size: 1.3rem;
        color: rgba(247, 252, 252, 0.6);
    }

    .footer {
        position: relative;
        background: rgba(12, 13, 14, 0.72);
        height: 8rem;
        width: 100%;
        top: 10rem;
    }

    .footer .info {
        position: absolute;
        left: 15%;
        line-height: 0.8rem;
        padding: 1rem 0 1rem 0;
    }

    .footer p {
        font-size: 0.6rem;
        color: rgba(236, 230, 230, 0.85);
    }

    .footer a {
        font-size: 0.6rem;
        color: rgba(236, 230, 230, 0.85);
    }

}