diff --git a/routes/css.cpp b/routes/css.cpp
index 3638df6..4ae4a70 100644
--- a/routes/css.cpp
+++ b/routes/css.cpp
@@ -29,7 +29,7 @@ html {
     font-family: sans-serif;
     padding: 10px;
 }
-p {
+p, details {
     margin-top: 1em;
     margin-bottom: 1em;
 }
diff --git a/servehelper.cpp b/servehelper.cpp
index e92d956..b33fec2 100644
--- a/servehelper.cpp
+++ b/servehelper.cpp
@@ -176,6 +176,15 @@ Element serialize_post(const httplib::Request& req, const std::string& server, c
         : "Created: "s + full_time(post.created_at) + "\nEdited: " + full_time(post.edited_at);
     const char* time_badge = post.edited_at < 0 ? "" : " (edited)";
 
+    Node contents = preprocess_html(req, server, post.emojis, post.content);
+    if (post.sensitive) {
+        std::string spoiler_text = !post.spoiler_text.empty() ? post.spoiler_text : "See more";
+        contents = Element("details", {
+            Element("summary", {preprocess_html(req, post.emojis, std::move(spoiler_text))}),
+            std::move(contents),
+        });
+    }
+
     Element div("div", {{"class", "post"}}, {
         Element("div", {{"class", "post-header"}}, {
             Element("a", {{"href", get_origin(req) + '/' + server + "/@" + post.account.acct(false)}}, {
@@ -190,7 +199,7 @@ Element serialize_post(const httplib::Request& req, const std::string& server, c
             }),
         }),
 
-        preprocess_html(req, server, post.emojis, post.content),
+        contents,
     });
     return div;
 }