*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: sans-serif;
}

nav{
    width: 100%;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid #cccccc;
    background: #fff;
    position: fixed;
    top: 0;
    z-index: 1000;
}

nav .left .logo img {
    width: 100px;
    margin: 5px 0 ;
    cursor: pointer;
}

nav .left {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-left: 10px;
}

nav .left .search_bar {
    width: 250px;
    height: 40px;
    background: #efefef;
    border-radius: 30px;
    padding: 0 10px;
    margin-top: 10px ;
    position: relative;
    left: 15px;
}

nav .left .search_bar i {
    line-height: 40px;
    font-size: 19px;
    color: #919191;
    margin-right: 5px;

}
nav .left .search_bar input {
    background: transparent;
    outline: none;
    border: 0;
    font-size: 16px;
    width: 200px;
}
nav .center {
    position: relative;
    right: 45px;

}

nav .center i {
    margin: 0 45px 0 45;
    font-size: 22px;
}
 nav .center i:hover{
    color:#45abff ;
    cursor: pointer;
 }

 nav .right {
    display: flex;
    align-items: center;
    margin-right: 10px;
 }

 nav .right i {
    width: 35px;
    height: 35px;
    border-radius: 50%;
    background: #efefef;
    line-height: 35px;
    padding-left: 8px ;
    font-size: 18px;
    margin-left: 8px;
    cursor: pointer;
 }


 nav .right img {
    width: 35px;
    height: 35px;
    object-fit: cover;
    object-position: center;
    border-radius: 50%;
    margin-left: 8px;
    line-height: 45px;
    cursor: pointer;
 }


 /* main */
 .main{
display: flex;
margin-top: 60px;
background: #f5f5f5;
 }


 .main .left{
    width: 25%;
    height: 92vh;
    overflow: hidden;
    /* overflow-y: scroll; */
    background: red;
    padding: 20px 6px 5px 10px;
    position: fixed;

 }