best way to make nav bar css code example

Example: top navbar css

/* This is the css for the nav bar*/

nav{

    display: flex;
    align-items: center;
    position: sticky;
    top: 0px;
    align-items: center;
    min-height: 8vh;
    
}

nav::before{
    content: "";
    background-color: rgb(255, 255, 255);
    position: absolute;
    top:0px;
    left:0px;
    height: 100%;
    width:100%;
    z-index: -1;
    opacity: 0.4;
}


#logo{
    color:rgb(0, 0, 0);
    text-transform: uppercase;
    letter-spacing: 5px;
    margin-left: 20px;
    margin-right: 60px;
    font-size: 22px;
}

.nav-links{
    display: flex;
    justify-content: space-around;
    width: 18%;
}
.nav-links li{
    list-style: none;
    display: inline-block;
    
}

#N1{
    margin-left: 20px;
    margin-right: 10px;
}
#N2{
    padding-left: 5px;
}

.nav-links a{
    color:rgb(0, 0, 0);
    font-size: 20px;
     text-decoration: none;  
     letter-spacing: 3px; 
    font-weight: bold;
    width: 150px;
    display: inline-block;
    text-align: center;
       
}

.cool-link::after{
    content: '';
    display: block;
    width: 0;
    height: 2px;
    background: rgb(0, 0, 0);
    transition: width .3s;
}
.cool-link:hover::after{
    width:100%;
    transition:width .3s;
}
/* designing of the buttons */
.btn{
    border: 1px solid #3498db;
    background: none;
    padding: 10px 20px;
    font-size: 25px;
    font-family: "montserrat";
    cursor: pointer;
    margin: 10px;
    transition: 0.8s;
    position: relative;
    overflow: hidden;
    text-decoration: none;
  }
  .btn::before{
    content: "";
    position: absolute;
    left: 0;
    width: 100%;
    height: 0%;
    background: #3498db;
    z-index: -1;
    transition: 0.8s;
   
  }
  .btn a{
    text-decoration: none;
    color:#fff;
    
  }
  .btn4{
    color: #fff;
    
  }
  
  .btn4:hover{
     color:black ;   /*  change the color*/
  }
  
  
  .btn4::before{
    bottom: 0;
    border-radius: 50% 50% 0 0;
  }
  .btn4::before{
    height: 180%;
  }
  
  .btn4:hover::before{
    height: 0%;
  }


/* button ends */

.burger{
    position: absolute;
    right: 30px;
    cursor: pointer;
    display: none;
}
.burger div{
    width: 25px;
    height: 3px;
    background-color: rgb(5, 5, 5);
    margin: 5px;
}


/* Nav bar in the mobile version*/

@media screen and (max-width: 670px)
{
     body{
        overflow-x: hidden;
    } 
    
    .nav-links{
        position: absolute;
        right: 0px;
        height: 25vh;
        top: 8vh;
        background-color: rgb(241, 241, 241);
        
        
        display: flex;
        flex-direction: column;
        align-items: center;
        width: 50%;
        transform: translateX(100%);
        transition: transform 0.3s ease-in;
       /* canging the z index of the */

    }

    .nav-links a{
        color:rgb(0, 0, 0);
        font-size: 20px;
         text-decoration: none;  
         letter-spacing: 3px; 
        font-weight: bold;
       
        display: inline-block;
        width: 150px;
        text-align: center;
        margin-left: 50px; 
    }
    
    .nav-active{
        transform: translateX(0%);
    }
    .burger{
        display: block;
    }
  
}