{% macro book_cover_image(book_id, book_title) -%}
    <img
        srcset="{{ url_for('web.get_cover', book_id=book_id, resolution=1) }} 1x,
                {{ url_for('web.get_cover', book_id=book_id, resolution=2) }} 2x"
        src="{{ url_for('web.get_cover', book_id=book_id) }}"
        alt="{{ book_title }}"
    />
{%- endmacro %}