*{
    margin: 0 auto;
}
.nav{
    position: fixed;
    font-weight: 700;
    display: flex;
    justify-content: space-evenly;
    align-items: center;
    height: 65px;
    width: 100%;
    font-size: 14px;
    color: white;
    background-color: rgba(0, 0, 0, 0);
    opacity: 0.6;
    z-index: 10;
    text-align: center;
}
.logo {
    width: 48px;
    height: 48px;
    border-radius: 40%;
}

.logo img {
    width: 100%;
}

ul{
    display: flex;
    justify-content:center;
    flex-wrap: nowrap;
}

ul li{
   
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    height: 65px;
}
 ul a{
    color: white;
}

ul a:hover{
    color: red;
}

.nav-l li{
    margin-left: 50px;
}

.nav-2 span{
    margin-left: 30px;
    margin-right: 30px;
}
.box{
    display: flex;
    flex-direction: column;
    justify-content: center;

}
.last{
    display: flex;
    width: 100%;
    justify-content: space-around;
    margin-top: 10px;
}

.last img{
    width: 100%;
}
.last-1{
    flex:1;
}
.last-2{
    flex:1;
}


/*关于小米*/
.big-3{
    padding-bottom: 5px;
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    align-items: center;
    
}
.big-3 img{
    width: 1226px;
}
.big-4{
    padding-bottom: 5px;
    background-color: rgb(250,250,250);
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    align-items: center;
    
}

.big-4 img{
    width: 1226px;
}