diff --git a/docs/requirements.md b/docs/requirements.md
new file mode 100644
index 0000000000..d1724225f3
--- /dev/null
+++ b/docs/requirements.md
@@ -0,0 +1,6 @@
+# 기능 요구 사항
+
+## 1단계 - HTTP 서버 구현하기
+- [x] 1\. GET `index.html` 응답하기
+- [x] 2\. CSS 지원하기
+- [x] 3\. Query String 파싱
diff --git a/study/build.gradle b/study/build.gradle
index 5c69542f84..7bdce4f751 100644
--- a/study/build.gradle
+++ b/study/build.gradle
@@ -19,7 +19,7 @@ repositories {
 dependencies {
     implementation 'org.springframework.boot:spring-boot-starter-web'
     implementation 'org.springframework.boot:spring-boot-starter-webflux'
-    implementation 'ch.qos.logback:logback-classic:1.5.7'
+    implementation 'org.springframework.boot:spring-boot-starter-thymeleaf'
     implementation 'org.apache.commons:commons-lang3:3.14.0'
     implementation 'com.fasterxml.jackson.core:jackson-databind:2.17.1'
     implementation 'pl.allegro.tech.boot:handlebars-spring-boot-starter:0.4.1'
diff --git a/study/src/main/java/cache/com/example/GreetingController.java b/study/src/main/java/cache/com/example/GreetingController.java
index c0053cda42..22a24c36e1 100644
--- a/study/src/main/java/cache/com/example/GreetingController.java
+++ b/study/src/main/java/cache/com/example/GreetingController.java
@@ -1,11 +1,12 @@
 package cache.com.example;
 
+import jakarta.servlet.http.HttpServletResponse;
+
 import org.springframework.http.CacheControl;
 import org.springframework.http.HttpHeaders;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.GetMapping;
 
-import jakarta.servlet.http.HttpServletResponse;
 
 @Controller
 public class GreetingController {
diff --git a/study/src/main/java/cache/com/example/cachecontrol/CacheControlInterceptor.java b/study/src/main/java/cache/com/example/cachecontrol/CacheControlInterceptor.java
new file mode 100644
index 0000000000..1f3c4d4e0d
--- /dev/null
+++ b/study/src/main/java/cache/com/example/cachecontrol/CacheControlInterceptor.java
@@ -0,0 +1,21 @@
+package cache.com.example.cachecontrol;
+
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+import org.springframework.lang.Nullable;
+import org.springframework.web.servlet.HandlerInterceptor;
+import org.springframework.web.servlet.ModelAndView;
+
+public class CacheControlInterceptor implements HandlerInterceptor {
+
+    @Override
+    public void postHandle(
+            HttpServletRequest request,
+            HttpServletResponse response,
+            Object handler,
+            @Nullable ModelAndView modelAndView
+    ) {
+        response.setHeader("Cache-Control", "no-cache, private");
+    }
+}
diff --git a/study/src/main/java/cache/com/example/cachecontrol/CacheWebConfig.java b/study/src/main/java/cache/com/example/cachecontrol/CacheWebConfig.java
index 305b1f1e1e..7959008433 100644
--- a/study/src/main/java/cache/com/example/cachecontrol/CacheWebConfig.java
+++ b/study/src/main/java/cache/com/example/cachecontrol/CacheWebConfig.java
@@ -9,5 +9,7 @@ public class CacheWebConfig implements WebMvcConfigurer {
 
     @Override
     public void addInterceptors(final InterceptorRegistry registry) {
+        registry.addInterceptor(new CacheControlInterceptor())
+                .addPathPatterns("/**");
     }
 }
diff --git a/study/src/main/java/cache/com/example/etag/EtagFilterConfiguration.java b/study/src/main/java/cache/com/example/etag/EtagFilterConfiguration.java
index 41ef7a3d9a..9c0f47b0ac 100644
--- a/study/src/main/java/cache/com/example/etag/EtagFilterConfiguration.java
+++ b/study/src/main/java/cache/com/example/etag/EtagFilterConfiguration.java
@@ -1,12 +1,19 @@
 package cache.com.example.etag;
 
+import org.springframework.boot.web.servlet.FilterRegistrationBean;
+import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.web.filter.ShallowEtagHeaderFilter;
 
 @Configuration
 public class EtagFilterConfiguration {
 
-//    @Bean
-//    public FilterRegistrationBean<ShallowEtagHeaderFilter> shallowEtagHeaderFilter() {
-//        return null;
-//    }
+    @Bean
+    public FilterRegistrationBean<ShallowEtagHeaderFilter> shallowEtagHeaderFilter() {
+        FilterRegistrationBean<ShallowEtagHeaderFilter> filterRegistrationBean = new FilterRegistrationBean<>();
+        filterRegistrationBean.setFilter(new ShallowEtagHeaderFilter());
+        filterRegistrationBean.addUrlPatterns("/etag");
+        filterRegistrationBean.addInitParameter("tag", "etag");
+        return filterRegistrationBean;
+    }
 }
diff --git a/study/src/main/java/cache/com/example/version/CacheBustingWebConfig.java b/study/src/main/java/cache/com/example/version/CacheBustingWebConfig.java
index 6da6d2c795..1ea48b7848 100644
--- a/study/src/main/java/cache/com/example/version/CacheBustingWebConfig.java
+++ b/study/src/main/java/cache/com/example/version/CacheBustingWebConfig.java
@@ -1,7 +1,10 @@
 package cache.com.example.version;
 
+import java.time.Duration;
+
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.http.CacheControl;
 import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
 
@@ -20,6 +23,8 @@ public CacheBustingWebConfig(ResourceVersion version) {
     @Override
     public void addResourceHandlers(final ResourceHandlerRegistry registry) {
         registry.addResourceHandler(PREFIX_STATIC_RESOURCES + "/" + version.getVersion() + "/**")
-                .addResourceLocations("classpath:/static/");
+                .addResourceLocations("classpath:/static/")
+                .setEtagGenerator(__ -> version.getVersion())
+                .setCacheControl(CacheControl.maxAge(Duration.ofDays(365)).cachePublic());
     }
 }
diff --git a/study/src/main/java/cache/com/example/version/ResourceVersion.java b/study/src/main/java/cache/com/example/version/ResourceVersion.java
index 27a2f22813..8c531e3efa 100644
--- a/study/src/main/java/cache/com/example/version/ResourceVersion.java
+++ b/study/src/main/java/cache/com/example/version/ResourceVersion.java
@@ -2,10 +2,11 @@
 
 import org.springframework.stereotype.Component;
 
-import jakarta.annotation.PostConstruct;
 import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;
 
+import jakarta.annotation.PostConstruct;
+
 @Component
 public class ResourceVersion {
 
diff --git a/study/src/main/resources/application.yml b/study/src/main/resources/application.yml
index 4e8655a962..4c735aea11 100644
--- a/study/src/main/resources/application.yml
+++ b/study/src/main/resources/application.yml
@@ -2,8 +2,12 @@ handlebars:
   suffix: .html
 
 server:
+  compression:
+    enabled: true
+    min-response-size: 10
   tomcat:
     accept-count: 1
     max-connections: 1
     threads:
+      min-spare: 2
       max: 2
diff --git a/study/src/test/java/study/FileTest.java b/study/src/test/java/study/FileTest.java
index e1b6cca042..e3f1b0bb88 100644
--- a/study/src/test/java/study/FileTest.java
+++ b/study/src/test/java/study/FileTest.java
@@ -1,13 +1,14 @@
 package study;
 
-import org.junit.jupiter.api.DisplayName;
-import org.junit.jupiter.api.Test;
+import static org.assertj.core.api.Assertions.assertThat;
 
+import java.io.IOException;
+import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.Collections;
 import java.util.List;
 
-import static org.assertj.core.api.Assertions.assertThat;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
 
 /**
  * 웹서버는 사용자가 요청한 html 파일을 제공 할 수 있어야 한다.
@@ -27,8 +28,9 @@ class FileTest {
     void resource_디렉터리에_있는_파일의_경로를_찾는다() {
         final String fileName = "nextstep.txt";
 
-        // todo
-        final String actual = "";
+        final var classLoader = getClass().getClassLoader();
+        final var url = classLoader.getResource(fileName);
+        final String actual = url.toString();
 
         assertThat(actual).endsWith(fileName);
     }
@@ -40,14 +42,14 @@ class FileTest {
      * File, Files 클래스를 사용하여 파일의 내용을 읽어보자.
      */
     @Test
-    void 파일의_내용을_읽는다() {
+    void 파일의_내용을_읽는다() throws IOException {
         final String fileName = "nextstep.txt";
 
-        // todo
-        final Path path = null;
+        final var classLoader = getClass().getClassLoader();
+        final var url = classLoader.getResource(fileName);
+        final Path path = Path.of(url.getPath());
 
-        // todo
-        final List<String> actual = Collections.emptyList();
+        final List<String> actual = Files.readAllLines(path);
 
         assertThat(actual).containsOnly("nextstep");
     }
diff --git a/study/src/test/java/study/IOStreamTest.java b/study/src/test/java/study/IOStreamTest.java
index 47a79356b6..9c15ad01d1 100644
--- a/study/src/test/java/study/IOStreamTest.java
+++ b/study/src/test/java/study/IOStreamTest.java
@@ -1,14 +1,26 @@
 package study;
 
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.atLeastOnce;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+
+import java.io.BufferedInputStream;
+import java.io.BufferedOutputStream;
+import java.io.BufferedReader;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FilterInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.nio.charset.StandardCharsets;
+
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Nested;
 import org.junit.jupiter.api.Test;
 
-import java.io.*;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.Mockito.*;
-
 /**
  * 자바는 스트림(Stream)으로부터 I/O를 사용한다.
  * 입출력(I/O)은 하나의 시스템에서 다른 시스템으로 데이터를 이동 시킬 때 사용한다.
@@ -54,6 +66,7 @@ class OutputStream_학습_테스트 {
              * OutputStream 객체의 write 메서드를 사용해서 테스트를 통과시킨다
              */
 
+            outputStream.write(bytes);
             final String actual = outputStream.toString();
 
             assertThat(actual).isEqualTo("nextstep");
@@ -78,6 +91,7 @@ class OutputStream_학습_테스트 {
              * flush를 사용해서 테스트를 통과시킨다.
              * ByteArrayOutputStream과 어떤 차이가 있을까?
              */
+            outputStream.flush();
 
             verify(outputStream, atLeastOnce()).flush();
             outputStream.close();
@@ -96,6 +110,7 @@ class OutputStream_학습_테스트 {
              * try-with-resources를 사용한다.
              * java 9 이상에서는 변수를 try-with-resources로 처리할 수 있다.
              */
+            try (outputStream) {}
 
             verify(outputStream, atLeastOnce()).close();
         }
@@ -128,7 +143,8 @@ class InputStream_학습_테스트 {
              * todo
              * inputStream에서 바이트로 반환한 값을 문자열로 어떻게 바꿀까?
              */
-            final String actual = "";
+            byte[] stream = inputStream.readAllBytes();
+            final String actual = new String(stream, StandardCharsets.UTF_8);
 
             assertThat(actual).isEqualTo("🤩");
             assertThat(inputStream.read()).isEqualTo(-1);
@@ -148,6 +164,7 @@ class InputStream_학습_테스트 {
              * try-with-resources를 사용한다.
              * java 9 이상에서는 변수를 try-with-resources로 처리할 수 있다.
              */
+            try (inputStream) {}
 
             verify(inputStream, atLeastOnce()).close();
         }
@@ -169,12 +186,12 @@ class FilterStream_학습_테스트 {
          * 버퍼 크기를 지정하지 않으면 버퍼의 기본 사이즈는 얼마일까?
          */
         @Test
-        void 필터인_BufferedInputStream를_사용해보자() {
+        void 필터인_BufferedInputStream를_사용해보자() throws IOException {
             final String text = "필터에 연결해보자.";
             final InputStream inputStream = new ByteArrayInputStream(text.getBytes());
-            final InputStream bufferedInputStream = null;
+            final InputStream bufferedInputStream = new BufferedInputStream(inputStream);
 
-            final byte[] actual = new byte[0];
+            final byte[] actual = bufferedInputStream.readAllBytes();
 
             assertThat(bufferedInputStream).isInstanceOf(FilterInputStream.class);
             assertThat(actual).isEqualTo("필터에 연결해보자.".getBytes());
@@ -197,16 +214,23 @@ class InputStreamReader_학습_테스트 {
          * 필터인 BufferedReader를 사용하면 readLine 메서드를 사용해서 문자열(String)을 한 줄 씩 읽어올 수 있다.
          */
         @Test
-        void BufferedReader를_사용하여_문자열을_읽어온다() {
+        void BufferedReader를_사용하여_문자열을_읽어온다() throws IOException {
             final String emoji = String.join("\r\n",
                     "😀😃😄😁😆😅😂🤣🥲☺️😊",
                     "😇🙂🙃😉😌😍🥰😘😗😙😚",
                     "😋😛😝😜🤪🤨🧐🤓😎🥸🤩",
                     "");
             final InputStream inputStream = new ByteArrayInputStream(emoji.getBytes());
+            final var inputStreamReader = new InputStreamReader(inputStream);
+            final BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
 
             final StringBuilder actual = new StringBuilder();
 
+            while (bufferedReader.ready()) {
+                actual.append(bufferedReader.readLine())
+                        .append("\r\n");
+            }
+
             assertThat(actual).hasToString(emoji);
         }
     }
diff --git a/tomcat/src/main/java/org/apache/coyote/http11/Http11Processor.java b/tomcat/src/main/java/org/apache/coyote/http11/Http11Processor.java
index bb14184757..783bc45a4d 100644
--- a/tomcat/src/main/java/org/apache/coyote/http11/Http11Processor.java
+++ b/tomcat/src/main/java/org/apache/coyote/http11/Http11Processor.java
@@ -1,17 +1,34 @@
 package org.apache.coyote.http11;
 
-import com.techcourse.exception.UncheckedServletException;
+import static org.apache.coyote.http11.http.MediaType.DEFAULT_CHARSET;
+import static org.apache.coyote.http11.http.MediaType.TEXT_CSS;
+import static org.apache.coyote.http11.http.MediaType.TEXT_HTML;
+
+import java.io.IOException;
+import java.net.Socket;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Map;
+import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
+
 import org.apache.coyote.Processor;
+import org.apache.coyote.http11.http.Headers;
+import org.apache.coyote.http11.http.HttpRequest;
+import org.apache.coyote.http11.http.HttpResponse;
+import org.apache.coyote.http11.http.HttpStatusCode;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.io.IOException;
-import java.net.Socket;
+import com.techcourse.db.InMemoryUserRepository;
+import com.techcourse.exception.UncheckedServletException;
 
 public class Http11Processor implements Runnable, Processor {
 
     private static final Logger log = LoggerFactory.getLogger(Http11Processor.class);
 
+    private static final ClassLoader CLASS_LOADER = ClassLoader.getSystemClassLoader();
+
     private final Socket connection;
 
     public Http11Processor(final Socket connection) {
@@ -29,19 +46,65 @@ public void process(final Socket connection) {
         try (final var inputStream = connection.getInputStream();
              final var outputStream = connection.getOutputStream()) {
 
-            final var responseBody = "Hello world!";
+            final var request = new HttpRequest(inputStream);
+
+            String body = mapResource(request);
 
-            final var response = String.join("\r\n",
-                    "HTTP/1.1 200 OK ",
-                    "Content-Type: text/html;charset=utf-8 ",
-                    "Content-Length: " + responseBody.getBytes().length + " ",
-                    "",
-                    responseBody);
+            final var headers = new Headers();
+            headers.put("Content-Type", contentType(request.getAccept()));
+            headers.put("Content-Type", DEFAULT_CHARSET);
+            headers.put("Content-Length", String.valueOf(body.getBytes().length));
 
-            outputStream.write(response.getBytes());
+            final var httpResponse = new HttpResponse(
+                    request.getHttpVersion(),
+                    HttpStatusCode.OK,
+                    headers,
+                    body
+            );
+
+            outputStream.write(httpResponse.getBytes());
             outputStream.flush();
         } catch (IOException | UncheckedServletException e) {
             log.error(e.getMessage(), e);
         }
     }
+
+    private String mapResource(final HttpRequest request) throws IOException {
+        String body = "";
+        if (Objects.equals(request.getPath(), "/")) {
+            body = "Hello world!";
+        }
+        if (Objects.equals(request.getPath(), "/index.html")) {
+            var url = CLASS_LOADER.getResource("static" + request.getPath());
+            body = Files.readString(Path.of(url.getPath()));
+        }
+        if (Objects.equals(request.getPath(), "/css/styles.css")) {
+            var url = CLASS_LOADER.getResource("static" + request.getPath());
+            body = Files.readString(Path.of(url.getPath()));
+        }
+        if (Objects.equals(request.getPath(), "/login")) {
+            var url = CLASS_LOADER.getResource("static" + request.getPath() + ".html");
+            body = Files.readString(Path.of(url.getPath()));
+            String queryString = request.getQueryString();
+            if (!queryString.isBlank()) {
+                Map<String, String> queryParams = new ConcurrentHashMap<>();
+                var params = queryString.split("&");
+                for (String param : params) {
+                    String[] keyValue = param.split("=");
+                    queryParams.put(keyValue[0], keyValue[1]);
+                }
+                var account = queryParams.get("username");
+                var user = InMemoryUserRepository.findByAccount(account).orElse(null);
+                log.info("user: {}", user);
+            }
+        }
+        return body;
+    }
+
+    private String contentType(final String accept) {
+        if (accept != null && accept.contains(TEXT_CSS)) {
+            return TEXT_CSS;
+        }
+        return TEXT_HTML;
+    }
 }
diff --git a/tomcat/src/main/java/org/apache/coyote/http11/http/Headers.java b/tomcat/src/main/java/org/apache/coyote/http11/http/Headers.java
new file mode 100644
index 0000000000..2d36ec60eb
--- /dev/null
+++ b/tomcat/src/main/java/org/apache/coyote/http11/http/Headers.java
@@ -0,0 +1,45 @@
+package org.apache.coyote.http11.http;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+public record Headers(Map<String, String> headers) {
+
+    private static final String DELIMITER = ": ";
+
+    public Headers() {
+        this(new LinkedHashMap<>());
+    }
+
+    public String get(final String name) {
+        return headers.get(name);
+    }
+
+    public void put(final String headerLine) {
+        if (!headerLine.contains(DELIMITER)) {
+            throw new IllegalArgumentException(headerLine);
+        }
+        final var split = headerLine.split(DELIMITER);
+        put(split[0], split[1]);
+    }
+
+    public void put(final String name, final String value) {
+        if (headers.containsKey(name)) {
+            headers.merge(name, value, (v1, v2) -> v1 + ";" + v2);
+            return;
+        }
+        headers.put(name, value);
+    }
+
+    @Override
+    public String toString() {
+        final var result = new StringBuilder();
+        for (String key : headers.keySet()) {
+            result.append(key)
+                    .append(": ")
+                    .append(headers.get(key))
+                    .append(" \r\n");
+        }
+        return result.toString();
+    }
+}
diff --git a/tomcat/src/main/java/org/apache/coyote/http11/http/HttpRequest.java b/tomcat/src/main/java/org/apache/coyote/http11/http/HttpRequest.java
new file mode 100644
index 0000000000..ed036d49ca
--- /dev/null
+++ b/tomcat/src/main/java/org/apache/coyote/http11/http/HttpRequest.java
@@ -0,0 +1,85 @@
+package org.apache.coyote.http11.http;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.StringJoiner;
+
+public class HttpRequest {
+
+    private final String method;
+    private final String requestURI;
+    private final String httpVersion;
+    private final Headers headers;
+    private final String body;
+
+    public HttpRequest(final InputStream inputStream) throws IOException {
+        final var reader = new InputStreamReader(inputStream);
+        final var buffer = new BufferedReader(reader);
+        final var requestLine = buffer.readLine();
+        final var requestLineSplit = requestLine.split(" ");
+        this.method = requestLineSplit[0];
+        this.requestURI = requestLineSplit[1];
+        this.httpVersion = requestLineSplit[2];
+        this.headers = createHeaders(buffer);
+        this.body = createBody(buffer);
+    }
+
+    private Headers createHeaders(final BufferedReader reader) throws IOException {
+        final var headers = new Headers();
+        var line = reader.readLine();
+        while (line != null && !line.isEmpty()) {
+            headers.put(line);
+            line = reader.readLine();
+        }
+        return headers;
+    }
+
+    private String createBody(final BufferedReader reader) throws IOException {
+        final var body = new StringJoiner("\r\n");
+        while (reader.ready()) {
+            var line = reader.readLine();
+            body.add(line);
+        }
+        return body.toString();
+    }
+
+    public String getPath() {
+        int index = requestURI.lastIndexOf("?");
+        if (index == -1) {
+            return requestURI;
+        }
+        return requestURI.substring(0, index);
+    }
+
+    public String getQueryString() {
+        int index = requestURI.lastIndexOf("?");
+        if (index == -1) {
+            return "";
+        }
+        return requestURI.substring(index + 1);
+    }
+
+    public String getHttpVersion() {
+        return httpVersion;
+    }
+
+    public String getAccept() {
+        return headers.get("Accept");
+    }
+
+    public String getBody() {
+        return body;
+    }
+
+    @Override
+    public String toString() {
+        final var result = new StringJoiner("\r\n");
+        final var requestLine = method + " " + requestURI + " " + httpVersion + " ";
+        return result.add(requestLine)
+                .add(headers.toString())
+                .add(body)
+                .toString();
+    }
+}
diff --git a/tomcat/src/main/java/org/apache/coyote/http11/http/HttpResponse.java b/tomcat/src/main/java/org/apache/coyote/http11/http/HttpResponse.java
new file mode 100644
index 0000000000..a52048074b
--- /dev/null
+++ b/tomcat/src/main/java/org/apache/coyote/http11/http/HttpResponse.java
@@ -0,0 +1,36 @@
+package org.apache.coyote.http11.http;
+
+import java.util.StringJoiner;
+
+public class HttpResponse {
+
+    private final String httpVersion;
+    private final HttpStatusCode httpStatusCode;
+    private final Headers headers;
+    private final String body;
+
+    public HttpResponse(String httpVersion, HttpStatusCode httpStatusCode, Headers headers, String body) {
+        this.httpVersion = httpVersion;
+        this.httpStatusCode = httpStatusCode;
+        this.headers = headers;
+        this.body = body;
+    }
+
+    public String getBody() {
+        return body;
+    }
+
+    public byte[] getBytes() {
+        return toString().getBytes();
+    }
+
+    @Override
+    public String toString() {
+        final var result = new StringJoiner("\r\n");
+        final var statusLine = httpVersion + " " + httpStatusCode + " ";
+        result.add(statusLine)
+                .add(headers.toString())
+                .add(body);
+        return result.toString();
+    }
+}
diff --git a/tomcat/src/main/java/org/apache/coyote/http11/http/HttpStatusCode.java b/tomcat/src/main/java/org/apache/coyote/http11/http/HttpStatusCode.java
new file mode 100644
index 0000000000..6ed1b100aa
--- /dev/null
+++ b/tomcat/src/main/java/org/apache/coyote/http11/http/HttpStatusCode.java
@@ -0,0 +1,23 @@
+package org.apache.coyote.http11.http;
+
+public enum HttpStatusCode {
+
+    OK(200, "OK");
+
+    private final int value;
+    private final String reasonPhrase;
+
+    HttpStatusCode(int value, String reasonPhrase) {
+        this.value = value;
+        this.reasonPhrase = reasonPhrase;
+    }
+
+    public int value() {
+        return value;
+    }
+
+    @Override
+    public String toString() {
+        return "%s %s".formatted(value, reasonPhrase);
+    }
+}
diff --git a/tomcat/src/main/java/org/apache/coyote/http11/http/MediaType.java b/tomcat/src/main/java/org/apache/coyote/http11/http/MediaType.java
new file mode 100644
index 0000000000..500ccb301a
--- /dev/null
+++ b/tomcat/src/main/java/org/apache/coyote/http11/http/MediaType.java
@@ -0,0 +1,8 @@
+package org.apache.coyote.http11.http;
+
+public class MediaType {
+
+    public static final String DEFAULT_CHARSET = "charset=utf-8";
+    public static final String TEXT_HTML = "text/html";
+    public static final String TEXT_CSS = "text/css";
+}
diff --git a/tomcat/src/test/java/org/apache/coyote/http11/Http11ProcessorTest.java b/tomcat/src/test/java/org/apache/coyote/http11/Http11ProcessorTest.java
index 2aba8c56e0..936768c5b0 100644
--- a/tomcat/src/test/java/org/apache/coyote/http11/Http11ProcessorTest.java
+++ b/tomcat/src/test/java/org/apache/coyote/http11/Http11ProcessorTest.java
@@ -1,14 +1,15 @@
 package org.apache.coyote.http11;
 
-import org.junit.jupiter.api.Test;
-import support.StubSocket;
+import static org.assertj.core.api.Assertions.assertThat;
 
 import java.io.File;
 import java.io.IOException;
 import java.net.URL;
 import java.nio.file.Files;
 
-import static org.assertj.core.api.Assertions.assertThat;
+import org.junit.jupiter.api.Test;
+
+import support.StubSocket;
 
 class Http11ProcessorTest {
 
@@ -35,7 +36,7 @@ void process() {
     @Test
     void index() throws IOException {
         // given
-        final String httpRequest= String.join("\r\n",
+        final String httpRequest = String.join("\r\n",
                 "GET /index.html HTTP/1.1 ",
                 "Host: localhost:8080 ",
                 "Connection: keep-alive ",
@@ -43,7 +44,7 @@ void index() throws IOException {
                 "");
 
         final var socket = new StubSocket(httpRequest);
-        final Http11Processor processor = new Http11Processor(socket);
+        final var processor = new Http11Processor(socket);
 
         // when
         processor.process(socket);
@@ -53,7 +54,35 @@ void index() throws IOException {
         var expected = "HTTP/1.1 200 OK \r\n" +
                 "Content-Type: text/html;charset=utf-8 \r\n" +
                 "Content-Length: 5564 \r\n" +
-                "\r\n"+
+                "\r\n" +
+                new String(Files.readAllBytes(new File(resource.getFile()).toPath()));
+
+        assertThat(socket.output()).isEqualTo(expected);
+    }
+
+    @Test
+    void css() throws IOException {
+        // given
+        final String httpRequest = String.join("\r\n",
+                "GET /css/styles.css HTTP/1.1 ",
+                "Host: localhost:8080 ",
+                "Accept: text/css,*/*;q=0.1 ",
+                "Connection: keep-alive ",
+                "",
+                "");
+
+        final var socket = new StubSocket(httpRequest);
+        final var processor = new Http11Processor(socket);
+
+        // when
+        processor.process(socket);
+
+        // then
+        final URL resource = getClass().getClassLoader().getResource("static/css/styles.css");
+        var expected = "HTTP/1.1 200 OK \r\n" +
+                "Content-Type: text/css;charset=utf-8 \r\n" +
+                "Content-Length: 211991 \r\n" +
+                "\r\n" +
                 new String(Files.readAllBytes(new File(resource.getFile()).toPath()));
 
         assertThat(socket.output()).isEqualTo(expected);