doc.silverstripe.org/src/theme/assets/scss/ss-docs.scss

body {
    font-family: -apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji;
}
.docs-wrapper {
    &.sidebar-visible {
        height: calc(100vh - 69px);
        overflow: hidden;        
    }
}
.header {
    @include box-shadow(none);
    border-bottom: 1px solid $gray-300;
}
.search-form {
    width: 75%;
    margin: 0 auto;
    .search-input {
        border-radius: 5px;
        background: $gray-200;
    }
}
.docs-sidebar {
    display: block;
    top: 95px;  
    @include box-shadow(none);
}

.docs-branding {
    display: flex;
    flex-direction: column;
    > .container {
        flex-grow: 1;
    }
}

.docs-sidebar-toggler {
    top: 0;
    background: transparent;
}

.theme-icon-holder {
    background: none;
}

.docs-nav {
    .nav-link {
        &::before {
            background: none;
        }
        &.section {
            &::before {
                background: $gray-700;
            }
            &.active {
                &::before {
                    background: $theme-color-primary;
                }
            }
        }        
    }
    .nav-item {
        margin-left: 0;
        &.section-title {
            margin: 1rem 0;
        }
        &.third-level {
            margin-left: 2rem;
        }
    }
}

code {
    padding: 0;
}

.docs-logo-wrapper {
    width: 300px;
    position: static;
    display: flex;
    justify-content: flex-start;
    align-items: center;
    padding: 0 1rem;
    .site-logo {
        .navbar-brand {
            font-size: 1rem;
            padding: 0;
            margin: 0;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            span {
                text-transform: uppercase;
                font-size: 0.8rem;
                color: $gray-700;
            }
        }
        img {
            width: 7rem;
            height: 1.5rem;
        }
    }
}
.docs-top-utilities {
    flex-grow: 1;
    .social-list {
        margin: 0;
        width: 25%;
        li {
            margin: 0;
            width: auto;
            height: auto;
        }
        .version-select {
            display: flex;
            justify-content: space-around;
            align-items: center;
            width: 7rem;
            height: 100%;
            line-height: 1;
            color: $gray-800;
            label {
                font-size: 0.7rem;
                margin: 0;
            }
            select {
               appearance: none;
                border: 0;
                color: $gray-800;
                background: none;
                padding-right: 2rem;            
            }
            [data-icon] {
                pointer-events: none;
                margin-left: -2rem;
            }
        }
    }
}
.top-search-box {
    flex-grow: 1;
}

.navbar {
    justify-content: flex-start;
}

h1, h2, h3 {
    font-weight: 100;
    margin: 2rem 0 1rem 0;
}

.card-body {
    h5 {
        display: flex;
        align-items: center;
        justify-content: flex-start;
        .card-icon-holder { 
            flex-shrink: 0;
        }
    }
}

.github-edit {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    width: 100%;
    margin: 2rem 0;
    a {
        color: $gray-800;
    }
}

@media (max-width: 1200px) {
    .docs-logo-wrapper {
        width: auto;
        padding: 1rem;
    }
    .docs-top-utilities {
        padding: 0 1rem;
    }
    .docs-sidebar {
        transform: translateX(-150%);
        &.sidebar-visible {
            transform: translateX(0);
        }
    }
}

@media (max-width: 640px) {
    .docs-sidebar {
        flex-grow: 1;
        width: auto;
        left: 0;
        right: 0;
    }
    /* purgecss ignore */
    .algolia-autocomplete .ds-dropdown-menu {
        min-width: 400px;
    }
    .search-form {
        width: auto;
    }
}