diff --git a/apps/web/src/reader/readerRuntime.test.ts b/apps/web/src/reader/readerRuntime.test.ts
index dddefe8..d56d18c 100644
--- a/apps/web/src/reader/readerRuntime.test.ts
+++ b/apps/web/src/reader/readerRuntime.test.ts
@@ -212,6 +212,16 @@ describe("reader runtime helpers", () => {
     expect(verticalBranch).not.toContain('hidden={!imageSizes[item.page]}');
   });
 
+  it("starts vertical reader overflow from the top edge instead of centered content", () => {
+    const styles = readFileSync(new URL("../styles/app.css", import.meta.url), "utf8");
+    const verticalStage = styles.match(/\.reader-mode-vertical \.reader-stage\s*\{[^}]+\}/)?.[0] ?? "";
+    const verticalContent = styles.match(/\.reader-mode-vertical \.reader-content\s*\{[^}]+\}/)?.[0] ?? "";
+
+    expect(verticalStage).toContain("align-items: start");
+    expect(verticalStage).toContain("overflow-anchor: none");
+    expect(verticalContent).toContain("align-self: start");
+  });
+
   it("detects fullscreen support and active fullscreen element", () => {
     const fullscreenElement = { requestFullscreen: () => Promise.resolve() } as unknown as HTMLElement;
     const regularElement = {} as HTMLElement;
diff --git a/apps/web/src/styles/app.css b/apps/web/src/styles/app.css
index 833bf1b..ff0e1f4 100644
--- a/apps/web/src/styles/app.css
+++ b/apps/web/src/styles/app.css
@@ -1035,8 +1035,17 @@ main.app-main-reader .reader-page {
 }
 
 .reader-mode-vertical .reader-content {
+  align-self: start;
   align-items: start;
+  justify-self: stretch;
   width: 100%;
+  height: auto;
+}
+
+.reader-mode-vertical .reader-stage {
+  align-items: start;
+  justify-items: center;
+  overflow-anchor: none;
 }
 
 .pdf-reader,