* {
    box-sizing: border-box;
}

body {
    font-family: Arial, Helvetica, sans-serif;
    margin: 0;
}

.header {
    padding: 80px;
    text-align: center;
    background: #1abc9c;
    color: antiquewhite;
}

    /* Increase the font size of the heading */
    .header h1 {
        font-size: 40px;
    }

/* Sticky navbar - toggles between relative and fixed, depending on the scroll position. It is positioned relative until a given offset position is met in the viewport - then it "sticks" in place (like position:fixed). The sticky value is not supported in IE or Edge 15 and earlier versions. However, for these versions the navbar will inherit default position */
.navbar {
    overflow: hidden;
    background-color: burlywood;
    position: sticky;
    position: -webkit-sticky;
    top: 0;
}

    /* Style the navigation bar links */
    .navbar a {
        float: left;
        display: block;
        color: white;
        text-align: center;
        padding: 14px 20px;
        text-decoration: none;
    }


        /* Right-aligned link */
        .navbar a.right {
            float: right;
        }

        /* Change color on hover */
        .navbar a:hover {
            background-color: #ddd;
            color: black;
        }

        /* Active/current link */
        .navbar a.active {
            background-color: #666;
            color: white;
        }

/* Column container */
.row {
    display: -ms-flexbox; /* IE10 */
    display: flex;
    -ms-flex-wrap: wrap; /* IE10 */
    flex-wrap: wrap;
}

/* Create two unequal columns that sits next to each other */
/* Sidebar/left column */
.side {
    -ms-flex: 30%; 
    flex: 30%;
    background-color: #f1f1f1;
    padding: 20px;
}

/* Main column */
.main {
    -ms-flex: 70%; 
    flex: 70%;
    background-color: white;
    padding: 20px;
    text-align: center;
}

.liste {
    display: block;
    position: relative;
    padding-left: 35px;
    margin-bottom: 12px;
    cursor: pointer;
    font-size: 22px;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}
/* Create a custom checkbox */
.checkmark {
    position: center;
    top: 0;
    left: 0;
    height: 25px;
    width: 25px;
    background-color: #eee;
}

/* On mouse-over, add a grey background color */
.liste:hover input ~ .checkmark {
    background-color: #ccc;
}

/* When the checkbox is checked, add a blue background */
.liste input:checked ~ .checkmark {
    background-color: #2196F3;
}

/* Create the checkmark/indicator (hidden when not checked) */
.checkmark:after {
    content: "";
    position: absolute;
    display: none;
}

/* Show the checkmark when checked */
.liste input:checked ~ .checkmark:after {
    display: block;
}

/* Style the checkmark/indicator */
.liste .checkmark:after {
    left: 9px;
    top: 5px;
    width: 5px;
    height: 10px;
    border: solid white;
    border-width: 0 3px 3px 0;
    -webkit-transform: rotate(45deg);
    -ms-transform: rotate(45deg);
    transform: rotate(45deg);
}

/* Fake image, just for this example */
.fakeimg {
    background-color: #aaa;
    width: 100%;
    padding: 20px;
}

/* Footer */
.footer {
    padding: 20px;
    text-align: center;
    background: #ddd;
}

/* Responsive layout - when the screen is less than 700px wide, make the two columns stack on top of each other instead of next to each other */
@media screen and (max-width: 700px) {
    .row {
        flex-direction: column;
    }
}

/* Responsive layout - when the screen is less than 400px wide, make the navigation links stack on top of each other instead of next to each other */
@media screen and (max-width: 400px) {
    .navbar a {
        float: none;
        width: 100%;
    }
}