diff --git a/a11y/index.html b/a11y/index.html
index 12fa3e7..e525729 100644
--- a/a11y/index.html
+++ b/a11y/index.html
@@ -1,16 +1,14 @@
-<!doctype html>
-<html lang="en">
-
-<head>
-  <meta charset="UTF-8" />
-  <link rel="icon" type="image/svg+xml" href="/vite.svg" />
-  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Accessibility</title>
-</head>
-
-<body>
-  <div id="root"></div>
-  <script type="module" src="/src/main.tsx"></script>
-</body>
+<!DOCTYPE html>
+<html lang="ko">
+  <head>
+    <meta charset="UTF-8" />
+    <link rel="icon" type="image/svg+xml" href="/vite.svg" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Accessibility</title>
+  </head>
 
+  <body>
+    <div id="root"></div>
+    <script type="module" src="/src/main.tsx"></script>
+  </body>
 </html>
diff --git a/a11y/src/App.tsx b/a11y/src/App.tsx
index a8159f9..b8fecc8 100644
--- a/a11y/src/App.tsx
+++ b/a11y/src/App.tsx
@@ -6,11 +6,11 @@ import FlightBooking from "./components/FlightBooking";
 function App() {
   return (
     <div className="app">
-      <div className="app-main">
-        <div className="flight-booking-container">
+      <main className="app-main">
+        <section className="flight-booking-container">
           <FlightBooking />
-        </div>
-      </div>
+        </section>
+      </main>
     </div>
   );
 }
diff --git a/a11y/src/components/FlightBooking.css b/a11y/src/components/FlightBooking.css
index d9d6083..5235c41 100644
--- a/a11y/src/components/FlightBooking.css
+++ b/a11y/src/components/FlightBooking.css
@@ -34,7 +34,7 @@
   width: 30px;
   height: 30px;
   border-radius: 16px;
-  border: 1px solid #C0C0C0;
+  border: 1px solid #c0c0c0;
   background-color: #fff;
   cursor: pointer;
   display: flex;
@@ -61,3 +61,15 @@
   border-radius: 4px;
   cursor: pointer;
 }
+
+.visually-hidden {
+  position: absolute;
+  width: 1px;
+  height: 1px;
+  padding: 0;
+  margin: -1px;
+  overflow: hidden;
+  clip: rect(0, 0, 0, 0);
+  white-space: nowrap;
+  border: 0;
+}
diff --git a/a11y/src/components/FlightBooking.tsx b/a11y/src/components/FlightBooking.tsx
index 313cab3..d22311c 100644
--- a/a11y/src/components/FlightBooking.tsx
+++ b/a11y/src/components/FlightBooking.tsx
@@ -6,26 +6,51 @@ const MAX_PASSENGERS = 3;
 
 const FlightBooking = () => {
   const [adultCount, setAdultCount] = useState(1);
+  const [statusMessage, setStatusMessage] = useState("");
 
   const incrementCount = () => {
+    if (adultCount === MAX_PASSENGERS) {
+      setStatusMessage("최대 승객 수에 도달했습니다");
+      return;
+    }
+
     setAdultCount((prev) => Math.min(MAX_PASSENGERS, prev + 1));
   };
 
   const decrementCount = () => {
+    if (adultCount === 1) {
+      setStatusMessage("최소 1명의 승객이 필요합니다");
+      return;
+    }
+
     setAdultCount((prev) => Math.max(1, prev - 1));
   };
 
   return (
     <div className="flight-booking">
+      {statusMessage && (
+        <div className="visually-hidden" role="alert">
+          {statusMessage}
+        </div>
+      )}
+
       <h2 className="heading-2-text">항공권 예매</h2>
       <div className="passenger-count">
         <span className="body-text">성인</span>
         <div className="counter">
-          <button className="button-text" onClick={decrementCount}>
+          <button
+            className="button-text"
+            onClick={decrementCount}
+            aria-label="성인 승객 감소"
+          >
             -
           </button>
-          <span>{adultCount}</span>
-          <button className="button-text" onClick={incrementCount}>
+          <span aria-live="polite">{adultCount}</span>
+          <button
+            className="button-text"
+            onClick={incrementCount}
+            aria-label="성인 승객 증가"
+          >
             +
           </button>
         </div>
diff --git a/a11y/vite.config.ts b/a11y/vite.config.ts
index 9cc50ea..d8d4e6c 100644
--- a/a11y/vite.config.ts
+++ b/a11y/vite.config.ts
@@ -4,4 +4,7 @@ import react from "@vitejs/plugin-react";
 // https://vitejs.dev/config/
 export default defineConfig({
   plugins: [react()],
+  server: {
+    host: "0.0.0.0",
+  },
 });
