diff --git a/templates/add.mustache b/templates/add.mustache
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+<!DOCTYPE html>
+<html lang="en">
+<head>
+<meta charset="utf-8" />
+<meta name="viewport" content="width=device-width, initial-scale=1" />
+<meta name="color-scheme" content="light dark" />
+<title>Spine — Add Book</title>
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/@picocss/pico@2.1.1/css/pico.min.css" />
+</head>
+<body>
+<main class="container">
+  <article style="max-width: 560px; margin-inline: auto;">
+    <header>
+      <strong>{{app_title}} · add book</strong>
+    </header>
+
+    <form method="post" action="/add">
+      <label>
+        Date added
+        <input type="date" name="date_added" />
+      </label>
+
+      <label>
+        Title *
+        <input type="text" name="title" required autofocus />
+      </label>
+
+      <label>
+        Author
+        <input type="text" name="author" list="authors-list" />
+        <datalist id="authors-list">
+          {{#existing_authors}}<option value="{{.}}">{{/existing_authors}}
+        </datalist>
+      </label>
+
+      <label>
+        Category
+        <input type="text" name="category" list="categories-list" />
+        <datalist id="categories-list">
+          {{#existing_categories}}<option value="{{.}}">{{/existing_categories}}
+        </datalist>
+      </label>
+
+      <label>
+        Format
+        <select name="format">
+          <option value="">—</option>
+          <option value="hardcover">Hardcover</option>
+          <option value="ebook">eBook</option>
+          <option value="audiobook">Audiobook</option>
+        </select>
+      </label>
+
+      <label>
+        ISBN
+        <input type="text" name="isbn" />
+      </label>
+
+      <label>
+        Cover (path)
+        <input type="text" name="cover" placeholder="covers/filename.jpg" />
+      </label>
+
+      <label>
+        Recommended by
+        <input type="text" name="rec_by" />
+      </label>
+
+      <label>
+        Why it's on your radar
+        <input type="text" name="rec_note" />
+      </label>
+
+      <label>
+        Initial note
+        <textarea name="initial_note" rows="3" placeholder="First impressions…"></textarea>
+      </label>
+
+      <button type="submit">Add book</button>
+    </form>
+  </article>
+</main>
+</body>
+</html>
