body {
    font-family: 'Arial';
    padding: 0;
    margin: 0;
}

h1 {
    font-size: 38px;
}

h2 {
    font-size: 32px;
}

h3 {
    font-size: 24px;
}

li {
    padding: 10px;
}

.header {
    color: white;
    margin: 0 auto;
    max-width: 900px;
    display: flex;
    justify-content: space-between;
}

.color-container {
    background-color: #001529;
}

.center {
    text-align: center;
}

.center-container {
    margin: 15 auto;
    max-width: 900px;
    border-radius: 3px;
}

.colored {
    background-color: #001529;
    color: white;
}

.center-container > h1 {
    padding: 20px 0 0 0;
}

.icon-link {
    display: flex;
    align-items: center;
}

.icon-link img {
    width: 20px;
}

.github {
    fill: white;
    width: 30px;

}

.demo {
    max-width: 900px;
    border: 1px solid #e6e6e6;
}

.header-subnav {
    display: flex;
    align-items: center;
}

.header-subnav div {
    padding: 0 10px 0 0;
}

.btn {
    display: inline-block;
    padding: 9px 15px;
    background-color: #99999942;
    color: white;
    border: 0;
    line-height: inherit;
    text-decoration: none;
    cursor: pointer;
    border-radius: 0;
}

.btn-primary {
    background-color: #3898EC;
}

.footer {
    text-align: center;
}