doc/themes/learn2/scss/theme/_main.scss

#main {
	background: $main-bg;
	margin: 0 0 $content-margin + $content-padding 0;
}

#body {
    img, .video-container {
        margin: 3rem auto;
        display: block;
        text-align: center;

        &.border {
            border: 2px solid #e6e6e6 !important;
            padding: 2px;
        }

        &.shadow {
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
        }
    }

    @extend .default-animation;
    position: relative;
    margin-left: $sidebar-width;
    min-height: 100%;

    .bordered {
        border: 1px solid #ccc;
    }

    .padding {
        @extend .default-animation;
        padding: 3rem ($body-margin + 2rem);

        @include breakpoint(desktop-only) {
            position: static;
            padding: 15px ($body-margin - 1rem);
        }

        @include breakpoint(mobile-only) {
            padding: 5px 1rem;
        }
    }

    h1 + hr {
        margin-top: -1.7rem;
        margin-bottom: 3rem;
    }

    #navigation {

        @include breakpoint(desktop-only) {
            position: static;
            margin-right: 0 !important;
            width: 100%;
            display: table;
        }
    }

    .nav {
        @extend .default-animation;
        position: fixed;
        top: 0;
        bottom: 0;
        width: $body-margin;
        font-size: 50px;
        height: 100%;
        cursor: pointer;
        display: table;
        text-align: center;
        > i {
            display: table-cell;
            vertical-align: middle;
            text-align: center;
        }

        @include breakpoint(desktop-only) {
            display: table-cell;
            position: static;
            top: auto;
            width: 50%;
            text-align: center;
            height: 100px;
            line-height: 100px;
            padding-top: 0;
            > i {
                display: inline-block;
            }
        }


        &:hover {
            background: $navbar-bg;
        }

        &.nav-pref {
            left: 0;
        }

        &.nav-next {
            right: 0;
        }
    }
}

#body-inner {
    margin-bottom: 5rem;
}

// Chapter title
#chapter {

    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    padding: 2rem 0;

    #body-inner {
        padding-bottom: 3rem;
        max-width: 80%;
    }

    h3 {
        font-family: $font-family-default;
        font-weight: $font-weight-regular;
        text-align: center;
    }

    h1 {
        font-size: 5rem;
        border-bottom: 4px solid $rule-color;
    }

    p {
        text-align: center;
        font-size: 1.2rem;
    }
}

#footer {
    padding: 3rem 1rem;
    color: darken($sidebar-link, 10%);
    font-size: 13px;

    p {
        margin: 0;
    }
}