diff --git a/src/anchor/pdf-viewer-adapter-spike.tsx b/src/anchor/pdf-viewer-adapter-spike.tsx
index f722e46..38cbc61 100644
--- a/src/anchor/pdf-viewer-adapter-spike.tsx
+++ b/src/anchor/pdf-viewer-adapter-spike.tsx
@@ -26,6 +26,13 @@ import {
   type PdfSelection,
   type ScaledPosition,
 } from "react-pdf-highlighter-plus";
+// pdfjs-dist's own pdf_viewer.css is the authoritative source for
+// text-layer positioning. The version bundled with
+// react-pdf-highlighter-plus is a minimal *override* (missing
+// `position: absolute`, `inset: 0`, and PDF.js 4.x's
+// `--scale-factor` handling) — load the real one first, then the
+// library's overrides on top.
+import "pdfjs-dist/web/pdf_viewer.css";
 import "react-pdf-highlighter-plus/style/style.css";
 import "react-pdf-highlighter-plus/style/pdf_viewer.css";
 import "./highlight-styles.css";