.sidebar {
    padding: 1.5rem 1.5rem 1.5rem 0; // no left padding on big screen
}

.sidebar-item {
    &:not(:last-child) {
        margin-bottom: 1rem; // space betreen sidebar items
    }

    h3 {
        margin-bottom: 0.25rem; // space betreen head3 & lists
    }

    ul {
        list-style-type: none;
        margin: 0 0.1rem; // little space
    }

    & > div,
    & > nav {
        margin: 0 0.1rem; // little space
    }

    & > img {
        margin: 0.5rem 0.25rem 0 0.25rem;
        width: 100%;
        border-radius: 2px;
    }
}

@media screen and (max-width: $width-md) {
    .sidebar {
        padding: 1.5rem;
        display: flex;
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: space-around;
    }

    .sidebar-item {
        width: 40%; // max 2 modules per line

        // space only at first 2 modules
        .sidebar-pages,
        .sidebar-tags {
            margin-bottom: 1rem;
        }

        .sidebar-links,
        .sidebar-bgm {
            margin-bottom: 0;
        }

        & > img {
            margin: 0.5rem 0.25rem 0 0.25rem;
            width: 75%;
            border-radius: 0.25rem;
        }
    }
}

// single page part
.sidebar-toc {
    ul ul {
        font-size: 0.875rem;
        padding-left: 0.5rem;
        margin-bottom: 0.25rem;
    }
}