index.css

body{
    padding: 0;
    margin: 0;
    /*TO REMOVE UNWANTED SPACING*/
    font-family: 'Ubuntu', sans-serif;
    height: 2000px;
}
header{
    background-color: rgb(48, 48, 48);
    color: white;
    padding: 10px;
}
.logo{
    display: inline-block;
}
.logodiv{
    display: flex;
    align-items: center;
}
nav img{
    height: 40px;
    margin: 5px;
}
nav label{
    font-size: 30px;
    font-weight: bold
}
nav ul{
    list-style: none;
    float: right;
    padding-inline-start: 0;  /*TO REMOVE THE SPACE IN STARTING OF THE LIST*/
    margin-right: 20px;
}
nav li{
    display: inline-block;
}
nav li a{
    text-decoration: none;
    color: white;
    border: 2px solid white;
    padding: 5px 15px;
    border-radius: 3px;
    margin-left: 20px;
    margin-right:20px;
    font-weight: bold;
}
nav li a:hover{
    color: rgb(50, 205, 171);
    border-color: rgb(50, 205, 171);
    background-color: rgba(255, 255, 255, 0.158);
}
li .active{
    color: rgb(50, 205, 171);
    border-color: rgb(50, 205, 171);
}
.main{
    background-image: url('keyboard.jpg');
    height: 550px;
    background-size: cover;
    background-position-x: center;
}
.submain{
    background-color: rgba(0, 0, 0, 0.5);
    height: 550px;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}
.submain h1{
    color: white;
    font-size: 60px;
    margin: 30px;
}
#icon{
    display: none;
}
@media screen and (max-width:850px){
    nav ul{
        margin-right: 0px;
    }
    nav li a{
        margin-right: 5px;
        margin-left: 5px;
    }
}
@media screen and (max-width:800px){
    #icon{
        display: block;
        float: right;
        line-height: 50px;
    }
    nav ul{
        position: fixed;
        width: 100%;
        background-color: rgb(50, 205, 171);
        top: 53px;/*LEFT 0 WAS DELETED*/    
        left: -100%;
        transition: all .5s;
    }
    nav li{
        display:block;
        padding: 10px;
        text-align: center;
    }
    nav li a{
        border: none;
        padding: none;
        font-size: 20px;
    }
    nav ul.show{
        left: 0;
    }
    li .active{
        color: rgb(0, 162, 255);
    }
    nav li a:hover{
        color: rgb(0, 162, 255);
        border-color: none;
        background-color: none;
    }
}
@media screen and (max-width:450px){
    nav label{
        font-size: 20px;
    }
    .submain h1{
        font-size: 40px;
    }
}