{% load static %}
<div class="card">
    <a href="{% url 'library:book_detail' pk=book.pk %}">
        <h3>{{ book }}</h3>
    </a>
    <p>{{ book.authors }}</p>
    {% if book.cover %}
    	<img src="{{ book.cover.url }}" class="cover" />
    {% else %}
    	<img src="{% static "ideasbox/img/default-book.png" %}" class="cover" />
    {% endif %}
</div>

{% load static %}
<div class="card">
    <a href="{% url 'library:book_detail' pk=book.pk %}">
        <h3>{{ book }}</h3>
    </a>
    <p>{{ book.authors }}</p>
    {% if book.cover %}
    	<a href="{% url 'library:book_detail' pk=book.pk %}">
    		<img src="{{ book.cover.url }}" class="cover" />
    	</a>
    {% else %}
    	<a href="{% url 'library:book_detail' pk=book.pk %}">
    		<img src="{% static "ideasbox/img/default-book.png" %}" class="cover" />
    	</a>
    {% endif %}
</div>

Add clickable image for library
Add clickable image for library
