@import url('https://fonts.googleapis.com/css2?family=Open+Sans&display=swap');
@import url('https://fonts.googleapis.com/css2?family=Roboto+Mono&display=swap');

body {
    box-sizing: border-box;
    width: 100%;
    padding: 0;
    margin: 0;
    background-color: #f3f3f3;
    font-family: 'Open Sans', sans-serif;
}

hr {
    height: 1px;
    border: none;
    color: #3333;
    background-color: #3333;
}

.main {
    box-sizing: border-box;
    width: 100%;
    padding: 20px;
    background-color: white;
}

.sidebar {
    box-sizing: border-box;
    width: 100%;
    padding: 20px;
    background-color: white;    
}

.footer {
    box-sizing: border-box;
    text-align: center;
    color: #888;
    width: 100%;
    margin: 0;
    padding: 20px;
}

.footer a {
    color: #888;
}

.heading .back-button span {
    display: inline-block;
    vertical-align: middle;
    margin-right: 10px;
}

.heading h2 {
    display: inline-block;
    vertical-align: middle;
}

.back-button {
    text-decoration: none;
    color: black;
}

.back-button:hover {
    color: gray;
}

.button-wrapper {
    margin: 20px auto 0 auto;
    text-align: center;
}

.button-wrapper a {
    text-decoration: none;
    color: black;
}

.button-content {
    box-sizing: border-box;
    display: inline-block;
    width: 100%;
    text-align: center;
    padding: 15px 50px;
    border-radius: 10px;
    background-color: #C3E6F7;
    transition: background-color 0.3s;
}

.button-content:hover {
    background-color: #9cd3f3;
}

.code-snippet {
    display: inline-block;
    background-color: rgb(228, 228, 228);
    padding: 1px 5px;
    margin: 1px 0;
    border-radius: 3px;
    font-family: 'Roboto Mono', monospace;
}

.code-box {
    display: block;
    margin: 10px 0;
    padding: 10px;
    white-space: pre-wrap;
}

img.center  {
    box-sizing: border-box;
    display: inline-block;
    max-width: 100%;
    position: relative;
    top: 0;
    left: 50%;
    margin-bottom: 20px;
    margin-right: -50%;
    transform: translate(-50%, 0%);
    -ms-transform: translate(-50%, 0%);
    -webkit-transform: translate(-50%, 0%);
    -moz-transform: translate(-50%, 0%);
    -o-transform: translate(-50%, 0%);
}

li {
    margin: 10px 0;
}

section {
    box-sizing: border-box;
    margin-bottom: 30px;
}

article {
    box-sizing: border-box;
    margin: 50px 0 0 0;
}

@media only screen and (min-width: 900px) {
    .main {
        width: 800px;
        margin: 20px auto;
        border-radius: 5px;
        box-shadow: 0 5px 7px #3333;
    }

    .sidebar {
        width: 800px;
        margin: 20px auto;
        border-radius: 5px;
        box-shadow: 0 5px 7px #3333;
    }

    .footer {
        width: 800px;
        margin: 20px auto;
    }
    
    .button-wrapper {
        margin: 20px auto 0 auto;
    }

    .button-content {
        width: auto;
    }

    img.center {
        max-width: 800px;
    }
}

@media only screen and (min-width: 1300px) {
    .sidebar {
        width: 200px;
        position: fixed;
        left: 20px;
        top: 30px;
        margin: 20px auto;
        border-radius: 5px;
        box-shadow: 0 5px 7px #3333;
    }
}