diff --git a/conf/sqlite_serve.conf b/conf/sqlite_serve.conf
index 5ba9784..fc7b502 100644
--- a/conf/sqlite_serve.conf
+++ b/conf/sqlite_serve.conf
@@ -32,15 +32,15 @@ http {
     server {
         listen 8080;
         server_name localhost;
-        
+
         root "server_root";
         charset utf-8;
 
-        # Serve static CSS file
-        location /static/ {
-            add_header "Content-Type" "text/css; charset=utf-8";
-            add_header "Cache-Control" "public, max-age=31536000";
-        }
+        # # Serve static CSS file
+        # location /static/ {
+        #     add_header "Content-Type" "text/css; charset=utf-8";
+        #     add_header "Cache-Control" "public, max-age=31536000";
+        # }
 
         # Homepage - Redirect to catalog
         location = / {
@@ -49,7 +49,7 @@ http {
 
         # Browse all books
         location = /books {
-            add_header "Content-Type" "text/html; charset=utf-8";
+            # add_header "Content-Type" "text/html; charset=utf-8";
             add_header "Cache-Control" "public, max-age=300";
             sqlite_db "book_catalog.db";
             sqlite_query "SELECT * FROM books ORDER BY rating DESC, title";
@@ -58,7 +58,7 @@ http {
 
         # Book detail by ID (named parameter)
         location = /book {
-            add_header "Content-Type" "text/html; charset=utf-8";
+            # add_header "Content-Type" "text/html; charset=utf-8";
             add_header "Cache-Control" "public, max-age=300";
             sqlite_db "book_catalog.db";
             sqlite_query "SELECT * FROM books WHERE id = :book_id";
@@ -68,7 +68,6 @@ http {
 
         # Filter by genre (named parameter)
         location = /genre {
-            add_header "Content-Type" "text/html; charset=utf-8";
             add_header "Cache-Control" "public, max-age=300";
             sqlite_db "book_catalog.db";
             sqlite_query "SELECT * FROM books WHERE genre = :genre ORDER BY rating DESC, title";
@@ -78,7 +77,6 @@ http {
 
         # Search by title (named parameter with LIKE)
         location = /search {
-            add_header "Content-Type" "text/html; charset=utf-8";
             sqlite_db "book_catalog.db";
             sqlite_query "SELECT * FROM books WHERE title LIKE '%' || :q || '%' ORDER BY rating DESC";
             sqlite_param :q $arg_q;
@@ -87,7 +85,6 @@ http {
 
         # Filter by minimum rating (named parameter)
         location = /top {
-            add_header "Content-Type" "text/html; charset=utf-8";
             sqlite_db "book_catalog.db";
             sqlite_query "SELECT * FROM books WHERE rating >= :min_rating ORDER BY rating DESC, title";
             sqlite_param :min_rating $arg_min;
@@ -96,7 +93,6 @@ http {
 
         # Year range filter (multiple named parameters)
         location = /era {
-            add_header "Content-Type" "text/html; charset=utf-8";
             sqlite_db "book_catalog.db";
             sqlite_query "SELECT * FROM books WHERE year >= :from AND year <= :to ORDER BY year DESC, title";
             sqlite_param :from $arg_from;
@@ -111,4 +107,3 @@ http {
         }
     }
 }
-
diff --git a/src/nginx_helpers.rs b/src/nginx_helpers.rs
index e674cf0..b141e59 100644
--- a/src/nginx_helpers.rs
+++ b/src/nginx_helpers.rs
@@ -1,5 +1,6 @@
 //! NGINX-specific helper functions
 
+use crate::content_type::ContentType;
 use crate::logging;
 use ngx::core::Buffer;
 use ngx::ffi::ngx_chain_t;
@@ -28,16 +29,16 @@ pub fn get_doc_root_and_uri(request: &mut Request) -> Result<(String, String), S
 
 /// Send HTML response
 pub fn send_response(request: &mut Request, body: &str) -> Status {
-    send_response_with_content_type(request, body, "text/html; charset=utf-8")
+    send_response_with_content_type(request, body, &ContentType::Html)
 }
 
-/// Send JSON response  
+/// Send JSON response
 pub fn send_json_response(request: &mut Request, body: &str) -> Status {
-    send_response_with_content_type(request, body, "application/json; charset=utf-8")
+    send_response_with_content_type(request, body, &ContentType::Json)
 }
 
 /// Create and send nginx response buffer with specified content type
-fn send_response_with_content_type(request: &mut Request, body: &str, _content_type: &str) -> Status {
+fn send_response_with_content_type(request: &mut Request, body: &str, content_type: &ContentType) -> Status {
     // Create output buffer
     let mut buf = match request.pool().create_buffer_from_str(body) {
         Some(buf) => buf,
@@ -54,9 +55,10 @@ fn send_response_with_content_type(request: &mut Request, body: &str, _content_t
 
     request.discard_request_body();
     request.set_status(http::HTTPStatus::OK);
-    
+
     // Set content type (nginx will handle it based on add_header in config or auto-detection)
     // For now, we rely on nginx config to set Content-Type via add_header directive
+    request.add_header_out("Content-Type", content_type.content_type_header());
 
     let rc = request.send_header();
     if rc == Status::NGX_ERROR || rc > Status::NGX_OK || request.header_only() {