html {
    scroll-behavior: smooth;
}

body {
    background-color: #f9f9f9f9;
}

.container {
    display: flex;
    height: 100vh;
}

nav {
    height: 100%;
    background-color: #333;
    padding: 20px;
    position: fixed;
}

hr {
    border-color: rgb(0, 0, 0);
}
#header-nav {
    color: #ffffff;
    -webkit-user-select: none;
    user-select: none;
}

nav a {
    display: block;
    margin-bottom: 10px;
    color: white;
    text-decoration: none;
    margin-top: 18px;
}

nav a:hover {
    text-decoration: underline;
}

main {
    flex: 1;
    padding: 20px;
    line-height: 1.5;
    margin-left: 20%;
}

h1 {
    font-size: 24px;
    margin-bottom: 20px;
}

p {
    font-size: 18px;
}

#code {
    font-size: medium;
}
article {
    text-align: justify;
    margin: 0 7% 0 7%;
}

section li {
    margin: 15px 0px 0px 40px;
}

code {
    display: block;
    text-align: left;
    justify-content: center;
    white-space: pre-line;
    position: relative;
    word-break: normal;
    word-wrap: normal;
    line-height: 2;
    background-color: #ececec;
    padding: 10px;
    margin: 15px;
    border-radius: 5px;
}

@media (max-width: 1000px) {
    main {
        margin-left: 25%;
    }
}
@media (max-width: 900px) {
    main {
        margin-left: 30%;
    }
}
@media (max-width: 750px) {
    main {
        margin-left: 35%;
    }
}
@media (max-width: 650px) {
    main {
        margin-left: 35%;
    }

    article {
        margin: 0 0 0 7%;
    }
}
@media (max-width: 610px) {
    nav {
        display: none;
        position: relative;              
    }

    main {
        margin-left: -7%;   
    }
}