My house is modern and I've just had the office fitted out in cornflower blue matt units. It won't stop me filling the bookshelves with my actual books I read - various travel books, plus a few vintage ones including Tolkien and my Wuthering Heights and Jayne Eyre set. I have some childhood books too, my fave being the velveteen rabbit. I have some vintage furniture and modern stuff but I don't care if it doesn't go together - I'm not creating an Instagram aesthetic, it's just things that mean a lot to me I don't care if they don't match!