diff --git a/src/components/wallet/InventoryTab.jsx b/src/components/wallet/InventoryTab.jsx
index 710c53f..c3eb772 100644
--- a/src/components/wallet/InventoryTab.jsx
+++ b/src/components/wallet/InventoryTab.jsx
@@ -1,4 +1,4 @@
-import { useState, useEffect } from 'react';
+import { useState, useEffect, useCallback } from 'react';
 import { getInventory } from '../../api/chain';
 import { useToast } from '../toast/useToast';
 
@@ -7,14 +7,16 @@ export default function InventoryTab() {
   const [inventory, setInventory] = useState(null);
   const [loading, setLoading] = useState(true);
 
-  useEffect(() => {
-    let cancelled = false;
+  const load = useCallback(() => {
+    setLoading(true);
     getInventory()
-      .then((data) => { if (!cancelled) setInventory(data); })
-      .catch(() => { if (!cancelled) toast.error('인벤토리를 불러오지 못했습니다.'); })
-      .finally(() => { if (!cancelled) setLoading(false); });
-    return () => { cancelled = true; };
-  }, []); // eslint-disable-line react-hooks/exhaustive-deps
+      .then(setInventory)
+      .catch(() => toast.error('인벤토리를 불러오지 못했습니다.'))
+      .finally(() => setLoading(false));
+  }, [toast]);
+
+  // eslint-disable-next-line react-hooks/set-state-in-effect
+  useEffect(() => { load(); }, [load]);
 
   if (loading) return <div className="wallet-spinner">불러오는 중...</div>;
 
diff --git a/src/components/wallet/WalletSummary.css b/src/components/wallet/WalletSummary.css
new file mode 100644
index 0000000..689c054
--- /dev/null
+++ b/src/components/wallet/WalletSummary.css
@@ -0,0 +1,51 @@
+.wallet-summary {
+  background: rgba(186, 205, 176, 0.06);
+  border: 1px solid rgba(186, 205, 176, 0.15);
+  border-radius: 10px;
+  padding: 20px 24px;
+  margin-bottom: 32px;
+  cursor: pointer;
+  transition: border-color 0.2s, background 0.2s;
+}
+
+.wallet-summary:hover {
+  border-color: rgba(186, 205, 176, 0.3);
+  background: rgba(186, 205, 176, 0.09);
+}
+
+.wallet-summary-title {
+  font-size: 0.75rem;
+  text-transform: uppercase;
+  color: rgba(255, 255, 255, 0.4);
+  letter-spacing: 0.08em;
+  margin: 0 0 12px;
+}
+
+.wallet-summary-balance {
+  font-size: 1.8rem;
+  font-weight: 700;
+  color: #BACDB0;
+  margin: 0;
+}
+
+.wallet-summary-stats {
+  display: flex;
+  gap: 24px;
+  margin-top: 12px;
+}
+
+.wallet-summary-stat {
+  font-size: 0.85rem;
+  color: rgba(255, 255, 255, 0.5);
+}
+
+.wallet-summary-stat strong {
+  color: rgba(255, 255, 255, 0.8);
+}
+
+@media (max-width: 768px) {
+  .wallet-summary-stats {
+    flex-direction: column;
+    gap: 8px;
+  }
+}
diff --git a/src/components/wallet/WalletSummary.jsx b/src/components/wallet/WalletSummary.jsx
index 01d283c..ca4feca 100644
--- a/src/components/wallet/WalletSummary.jsx
+++ b/src/components/wallet/WalletSummary.jsx
@@ -1,7 +1,7 @@
 import { useState, useEffect } from 'react';
 import { useNavigate } from 'react-router-dom';
 import { getBalance, getAssets, getInventory } from '../../api/chain';
-import '../../pages/WalletPage.css';
+import './WalletSummary.css';
 
 export default function WalletSummary() {
   const navigate = useNavigate();
diff --git a/src/pages/AdminPage.css b/src/pages/AdminPage.css
index 2e6ef46..e6146b9 100644
--- a/src/pages/AdminPage.css
+++ b/src/pages/AdminPage.css
@@ -147,4 +147,4 @@
   .admin-main {
     padding: 20px 12px 60px;
   }
-}
+}
\ No newline at end of file
diff --git a/src/pages/AuthPage.css b/src/pages/AuthPage.css
index a16860b..77cbe90 100644
--- a/src/pages/AuthPage.css
+++ b/src/pages/AuthPage.css
@@ -151,6 +151,13 @@
   border-color: rgba(186, 205, 176, 0.5);
 }
 
+.login-logo {
+  max-width: 120px;
+  height: auto;
+  margin: 0 auto 16px;
+  display: block;
+}
+
 .login-back {
   display: block;
   text-align: center;
diff --git a/src/pages/LoginPage.jsx b/src/pages/LoginPage.jsx
index 8d4316a..5debda0 100644
--- a/src/pages/LoginPage.jsx
+++ b/src/pages/LoginPage.jsx
@@ -14,6 +14,18 @@ export default function LoginPage() {
   const location = useLocation();
   const justRegistered = location.state?.registered;
 
+  const handleSSAFYLogin = async () => {
+    try {
+      const data = await getSSAFYLoginURL();
+      if (!data.url || !data.url.startsWith('https://')) {
+        throw new Error('유효하지 않은 로그인 URL입니다.');
+      }
+      window.location.href = data.url;
+    } catch {
+      setError('SSAFY 로그인 URL을 가져올 수 없습니다.');
+    }
+  };
+
   const handleSubmit = async (e) => {
     e.preventDefault();
     setError('');
@@ -84,17 +96,7 @@ export default function LoginPage() {
         <button
           type="button"
           className="btn-ssafy"
-          onClick={async () => {
-            try {
-              const data = await getSSAFYLoginURL();
-              if (!data.url || !data.url.startsWith('https://')) {
-                throw new Error('유효하지 않은 로그인 URL입니다.');
-              }
-              window.location.href = data.url;
-            } catch {
-              setError('SSAFY 로그인 URL을 가져올 수 없습니다.');
-            }
-          }}
+          onClick={handleSSAFYLogin}
         >
           SSAFY 계정으로 로그인
         </button>
diff --git a/src/pages/RegisterPage.jsx b/src/pages/RegisterPage.jsx
index 29c9fb9..29b13d4 100644
--- a/src/pages/RegisterPage.jsx
+++ b/src/pages/RegisterPage.jsx
@@ -5,6 +5,13 @@ import './AuthPage.css';
 
 const USERNAME_REGEX = /^[a-z0-9_-]{3,50}$/;
 
+function getPasswordStrength(pw) {
+  if (pw.length === 0) return { label: '', level: '' };
+  if (pw.length < 6) return { label: '약함', level: 'weak' };
+  if (pw.length < 10) return { label: '중간', level: 'medium' };
+  return { label: '강함', level: 'strong' };
+}
+
 export default function RegisterPage() {
   const [username, setUsername] = useState('');
   const [password, setPassword] = useState('');
@@ -18,13 +25,6 @@ export default function RegisterPage() {
   const showUsernameError = usernameTouched && username.length > 0 && !isUsernameValid;
   const showUsernameValid = usernameTouched && username.length > 0 && isUsernameValid;
 
-  const getPasswordStrength = (pw) => {
-    if (pw.length === 0) return { label: '', level: '' };
-    if (pw.length < 6) return { label: '약함', level: 'weak' };
-    if (pw.length < 10) return { label: '중간', level: 'medium' };
-    return { label: '강함', level: 'strong' };
-  };
-
   const passwordStrength = getPasswordStrength(password);
   const confirmMismatch = confirm.length > 0 && password !== confirm;
   const confirmMatch = confirm.length > 0 && password === confirm;
@@ -34,7 +34,7 @@ export default function RegisterPage() {
     setError('');
 
     const trimmed = username.trim().toLowerCase();
-    if (!trimmed) {
+    if (trimmed.length === 0) {
       setError('아이디를 입력해주세요.');
       return;
     }
@@ -42,7 +42,7 @@ export default function RegisterPage() {
       setError('아이디는 3자 이상이어야 합니다.');
       return;
     }
-    if (!/^[a-z0-9_-]+$/.test(trimmed)) {
+    if (!USERNAME_REGEX.test(trimmed)) {
       setError('아이디는 영문 소문자, 숫자, _, -만 사용 가능합니다.');
       return;
     }
@@ -70,7 +70,7 @@ export default function RegisterPage() {
     <div className="login-page">
       <div className="login-panel">
         <div className="login-header">
-          <img src="/images/logo.webp" alt="One of the Plans" style={{maxWidth: 120, height: 'auto', margin: '0 auto 16px', display: 'block'}} />
+          <img src="/images/logo.webp" alt="One of the Plans" className="login-logo" />
           <h1 className="game-title">One of the plans</h1>
           <p className="game-subtitle">MULTIPLAYER</p>
         </div>
@@ -128,12 +128,10 @@ export default function RegisterPage() {
               className={confirmMatch ? 'input-valid' : confirmMismatch ? 'input-invalid' : ''}
               aria-describedby="confirm-hint"
             />
-            {confirmMismatch && (
-              <span id="confirm-hint" className="input-hint input-hint-error">비밀번호가 일치하지 않습니다</span>
-            )}
-            {confirmMatch && (
-              <span id="confirm-hint" className="input-hint input-hint-success">비밀번호가 일치합니다 {'\u2713'}</span>
-            )}
+            <span id="confirm-hint" className={`input-hint ${confirmMismatch ? 'input-hint-error' : confirmMatch ? 'input-hint-success' : ''}`}>
+              {confirmMismatch && '비밀번호가 일치하지 않습니다'}
+              {confirmMatch && `비밀번호가 일치합니다 \u2713`}
+            </span>
           </div>
 
           {error && <p className="login-error" role="alert">{error}</p>}
diff --git a/src/pages/SSAFYCallbackPage.jsx b/src/pages/SSAFYCallbackPage.jsx
index f697dae..d693b5b 100644
--- a/src/pages/SSAFYCallbackPage.jsx
+++ b/src/pages/SSAFYCallbackPage.jsx
@@ -2,8 +2,9 @@ import { useEffect, useState, useRef } from 'react';
 import { useNavigate, useSearchParams } from 'react-router-dom';
 import { useAuth } from '../context/useAuth';
 import { ssafyCallback } from '../api/auth';
+import './AuthPage.css';
 
-// Inline styles are intentional for this simple callback/loading page — not worth a separate CSS file.
+// Inline styles are intentional for this simple callback/loading page — layout only, AuthPage.css handles buttons.
 export default function SSAFYCallbackPage() {
   const [error, setError] = useState('');
   const navigate = useNavigate();
@@ -39,7 +40,7 @@ export default function SSAFYCallbackPage() {
     return (
       <div style={{ textAlign: 'center', marginTop: '4rem' }}>
         <p style={{ color: '#e74c3c' }}>{error}</p>
-        <button onClick={() => navigate('/login', { replace: true })}>
+        <button className="btn-login" onClick={() => navigate('/login', { replace: true })}>
           로그인 페이지로 돌아가기
         </button>
       </div>
diff --git a/src/pages/WalletPage.css b/src/pages/WalletPage.css
index 22c06bd..74771a3 100644
--- a/src/pages/WalletPage.css
+++ b/src/pages/WalletPage.css
@@ -367,51 +367,6 @@
   background: rgba(186, 205, 176, 0.08);
 }
 
-/* Wallet summary card (HomePage) */
-.wallet-summary {
-  background: rgba(186, 205, 176, 0.06);
-  border: 1px solid rgba(186, 205, 176, 0.15);
-  border-radius: 10px;
-  padding: 20px 24px;
-  margin-bottom: 32px;
-  cursor: pointer;
-  transition: border-color 0.2s, background 0.2s;
-}
-
-.wallet-summary:hover {
-  border-color: rgba(186, 205, 176, 0.3);
-  background: rgba(186, 205, 176, 0.09);
-}
-
-.wallet-summary-title {
-  font-size: 0.75rem;
-  text-transform: uppercase;
-  color: rgba(255, 255, 255, 0.4);
-  letter-spacing: 0.08em;
-  margin: 0 0 12px;
-}
-
-.wallet-summary-balance {
-  font-size: 1.8rem;
-  font-weight: 700;
-  color: #BACDB0;
-  margin: 0;
-}
-
-.wallet-summary-stats {
-  display: flex;
-  gap: 24px;
-  margin-top: 12px;
-}
-
-.wallet-summary-stat {
-  font-size: 0.85rem;
-  color: rgba(255, 255, 255, 0.5);
-}
-
-.wallet-summary-stat strong {
-  color: rgba(255, 255, 255, 0.8);
-}
 
 .wallet-logo {
   height: 32px;
@@ -470,11 +425,6 @@
     align-items: stretch;
   }
 
-  .wallet-summary-stats {
-    flex-direction: column;
-    gap: 8px;
-  }
-
   .market-item {
     flex-direction: column;
     align-items: stretch;