@media screen and (max-width:720px){
     .     #master_footer{
          margin: 0px;
    padding: 0px;
/*     position: fixed; */
    width: 100%;
/*     bottom: 0px; */
/*     margin-bottom: -60px; */
     }
     #home_menu{
         height:100px;
	     position: fixed;
	     width: 100%;
	     top: 0px;
	     z-index: 999999;
     }
     .learn5{
         /* clear: both; */
    /* margin: 0px 0px 80px 0px; */
    /*background: url(../img/web_bg3@2x.png) no-repeat 0;*/
    background-position: 100%;
    background-size: cover;
    height: 200px;
    width: 100%;
    /* padding-bottom: 50px; */
    /* margin-top: -10rem; */
    margin-bottom: -7rem;
    background: #181C1F;
}
.down_btn{
          position: absolute;
    /* width: 241px; */
    height: 12px;
    font-size: 13px;
    font-family: Arial, Arial-Regular;
    font-weight: 400;
    color: #ffffff;
    right: 0;
    /* margin-top: 10rem;*/
}
.learn5 p:nth-child(2){
	   /* margin: 0px 1rem 0px 0px;
            width: 440px;*/
    /* float: left; */
    /* clear: both; */
   /* position: absolute;
    width: auto;
    height: 32px;
    font-size: 15px;
    font-family: Arial, Arial-Regular;
    font-weight: 400;
    text-align: left;
    color: #ffffff;
    left: 35%;
    margin-top: 5rem;*/
}
.bottom_title {
    text-align: center;
    /*color: #ff8627;*/
    font-size: 15px;
    font-weight: bold;
    padding-top: 3rem;
    font-family: AliHYAiHei-Beta;
    font-weight: 400;
    color: #FFFFFF;
    margin-right:10px;
}
.bottom_desc {
	    font-size: 12px;
    text-align: center;
    color: #ff8627;
    font-weight: 700;
    letter-spacing: 2px;
    margin-right: 10px;
}
.down_img{
     /* float: right; */
    /* padding-top: 100px; */
    background: url(../img/bg_web_img7.png) no-repeat 0;
    background-position: 100%;
    background-size: contain;
    height: 200px;
    /* left: 0px; */
    /* margin-top: 100px; */
    float: left;
    width: 40%;
    /* margin-top: 50px; */
    /* margin-left: 20%; */
        margin-left: 5px;
    margin-bottom: 0rem;
}
.down_txt{    font-size: 12px;
        font-family: PingFang SC, PingFang SC-Bold;
    color: #181C1F;
    }
button{
    border: none;
    background: #8045f900;
}
.android_btn{       
	    width: 90px;
    height: 30px;
    line-height: 30px;
    background: #ffffff;
    border-radius: 22.5px;
    margin-right: 10px;
    }
.google_btn img{width:5rem;}
.android_btn img{
	    width: 18px;
    height: 21px;
    margin-right: 10px;
    position: relative;
    margin-bottom: -5px;
	}
 }
 @media screen and (min-width:721px){
      #master_footer{
          margin: 0px;
    padding: 0px;
/*     position: fixed; */
    width: 100%;
/*     bottom: 0px; */
/*     margin-bottom: -60px; */
     }
     #home_menu{
         height:100px;
	     position: fixed;
	     width: 100%;
	     top: 0px;
	     z-index: 999999;
     }
     .learn5{
   clear: both;
    /* margin: 0px 0px 80px 0px; */
    /*background: url(../img/web_bg3@2x.png) no-repeat 0;*/
    /* background-position: center; */
    background-size: cover;
    height: 400px;
    width: 100%;
    /* padding-bottom: 50px; */
    margin-bottom: -50px;
        background: #181C1F;
}
.down_btn{
   position: absolute;
    /* width: 241px; */
    height: 12px;
    font-size: 13px;
    font-family: Arial, Arial-Regular;
    font-weight: 400;
    text-align: right;
    color: #ffffff;
    left: 50%;
    margin-top: 5rem;
}
.learn5 p:nth-child(2){
     /* width: 440px;
    /* float: left; */
    /* clear: both; */
    /*position: absolute;*/
    /* width: 241px; */
	/*height: 32px;
	font-size: 15px;
	font-family: Arial, Arial-Regular;
	font-weight: 400;
    text-align: left;
    color: #ffffff;
    left: 45%;
    margin-top: 8rem;*/
}
.down_img{
/*float: right; */
    /* padding-top: 100px; */
    background: url(../img/bg_web_img7@2x.png) no-repeat 0;
    /* background-position: top; */
    background-size: contain;
    height: 400px;
    left: 0px;
    /* margin-top: 100px; */
    float: left;
    width: 30%;
    /* margin-top: 50px; */
    /* margin-left: 20%;*/
}
button{
    border: none;
    background: #8045f900;
}
.google_btn{margin-right:50px;}
.google_btn img{width:160px;}
.android_btn{
	    width: 160px;
    height: 45px;
    background: #ffffff;
    border-radius: 22.5px;
    margin-right:2rem;
}

.android_btn img{    
	width: 18px;
    height: 21px;
    margin-right: 15px;
    position: relative;
    margin-bottom: -5px;}
.bottom_title{
	text-align: center;
    color: #ffffff;
    font-size: 25px;
    font-weight: bold;
    padding-top: 5rem;
    }
 .bottom_desc{
        text-align: center;
    color: #ff8627;
    font-weight: 700;
    letter-spacing: 2px;
 }   
 .down_txt{
          font-size: 16px;
    font-family: PingFang SC, PingFang SC-Bold;
   color: #181C1F;
 }
}