diff --git a/src/gateway/public-gateway.mjs b/src/gateway/public-gateway.mjs
index c83eacd..6d7b4b2 100644
--- a/src/gateway/public-gateway.mjs
+++ b/src/gateway/public-gateway.mjs
@@ -507,19 +507,30 @@ async function serve(res, name, reqPath, baseHref) {
           const cleanPath = reqPath.slice(1).replace(/\/+$/, "");
           // 1) Extensionless-URL support: /tld -> tld.html. Lets sites
           //    publish clean URLs without keeping mirror files around.
+          //    Base injection stays anchored at the directory of reqPath,
+          //    which is correct because tld.html is a flat file.
           if (!reqPath.endsWith("/")) {
             const htmlKey = cleanBase + cleanPath + ".html";
             const htmlHit = await aws.fetch(`${S3_ENDPOINT}/${htmlKey}`);
             if (htmlHit.ok) { up = htmlHit; }
           }
-          // 2) Directory-index: /docs -> docs/index.html
+          // 2) Directory-index: /docs -> docs/index.html. Redirect to add
+          //    the trailing slash instead of serving in place — otherwise
+          //    the injected <base> stays at the parent directory and any
+          //    relative asset/href inside the served page (e.g.
+          //    ./assets/favicon.svg on /theseus/index.html) resolves to
+          //    the WRONG directory. nginx behaves the same way.
           if (up.status === 404 && !reqPath.endsWith("/")) {
             const dirKey = cleanBase + cleanPath + "/index.html";
             const dir = await aws.fetch(`${S3_ENDPOINT}/${dirKey}`);
-            if (dir.ok) { up = dir; }
+            if (dir.ok) {
+              res.writeHead(302, { location: `${MOUNT}/${name}${reqPath}/` });
+              return res.end();
+            }
           }
           // 3) SPA root fallback — last resort so client-side routers
-          //    can pick up /katalogos, /anthemus, etc.
+          //    can pick up /katalogos, /anthemus, etc. Base stays at the
+          //    site root, which is what SPAs expect.
           if (up.status === 404) {
             const fallbackKey = cleanBase + "index.html";
             const fb = await aws.fetch(`${S3_ENDPOINT}/${fallbackKey}`);