* {
    margin: 0px;
    padding: 0px;
    box-sizing: border-box;
}

nav a {
    text-decoration: none;
    font-size: 30px;
    color: white;
    box-shadow: 0px 0px 25px 1px white;
    border-radius: 80px;
    padding: 7px 20px;
}

nav a:hover {
    background-color: white;
    color: black;
    font-weight: 800;
    text-shadow: 0px 0px 14px black;
}

nav ul li {
    margin: 28px 20px;
    list-style: none;
}

nav {
    box-shadow: 10px 0px 30px black;
    width: 550px;
    padding: 1px 10px;
    z-index: 3;
    display: inline-block;
    position: absolute;
    left: 0%;
    text-align: center;
    background-color: black;
    border-bottom-right-radius: 70px;
    border-right: 10px double yellow;
}

.up {
    background-color: black;
    color: aliceblue;
    font-size: 50px;
    padding: 19px 20px;
    text-align: center;
    text-shadow: 0px 0px 12px white;
}

.bx-menu {
    position: absolute;
    top: -2px;
    left: 20px;
    font-size: 100px;
}

.sidebar {
    position: absolute;
    left: -100%;
    transition: all 1.4s ease;
}

.sidebar.on {
    left: 0%;
}

#chevup {
    color: white;
    background-color: rgb(0, 0, 0, 0.84);
    border-radius: 100%;
    font-size: 90px;
    position: fixed;
    bottom: 7%;
    right: 7%;
    box-shadow: 0px 0px 24px 2px black;
}
.up b {
    font-size: 40px;
    color: aliceblue;
    margin-left: 55px;
}

html {
    scroll-behavior: smooth;
}

@media (max-width:900px) and (min-width:600px) {
    .up {
        font-size: 31px;
    }

    nav {
        width: 440px;
    }

    nav a {
        cursor: none;
        font-size: 22px;
    }

    .bx-menu {
        top: 6px;
        font-size: 66px;
    }

    #chevup {
        font-size: 70px;
    }
}

@media (max-width:600px) and (min-width:400px) {
    .up {
        font-size: 24px;
    }

    nav {
        width: 390px;
        padding: 0px;
    }

    .up b {
        font-size: 26px;
        margin-left: 55px;
    }

    nav a {
        cursor: none;
        font-size: 22px;
    }

    .bx-menu {
        top: 13px;
        left: 16px;
        font-size: 46px;
    }

    #chevup {
        font-size: 60px;
    }
}

@media (max-width:400px) and (min-width:300px) {
    .up {
        font-size: 20px;
    }

    nav {
        width: 290px;
        padding: 0px;
    }

    .up b {
        font-size: 18px;
        margin-left: 37px;
    }

    nav ul {
        margin: 10px;
    }

    nav a {
        cursor: none;
        font-size: 15px;
    }

    .bx-menu {
        top: 14.5px;
        left: 15px;
        font-size: 36px;
    }

    #chevup {
        font-size: 50px;
    }

    nav ul li {
        margin: 24px 0px;
    }
}