feat: 使用 Flask 重构网站，增加登录注册功能 🐶

- Python Flask 3.1 后端
- 用户注册/登录功能
- SQLite 数据库
- 响应式设计
- 默认管理员: yunxiafei / xu123654

static/css/style.css

@@ -0,0 +1,235 @@
+* {
+    margin: 0;
+    padding: 0;
+    box-sizing: border-box;
+}
+
+body {
+    min-height: 100vh;
+    display: flex;
+    justify-content: center;
+    align-items: center;
+    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
+    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
+}
+
+.container {
+    text-align: center;
+    padding: 60px 40px;
+    background: rgba(255, 255, 255, 0.95);
+    border-radius: 20px;
+    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
+    max-width: 600px;
+    width: 90%;
+    animation: fadeIn 0.6s ease-out;
+}
+
+@keyframes fadeIn {
+    from {
+        opacity: 0;
+        transform: translateY(30px);
+    }
+    to {
+        opacity: 1;
+        transform: translateY(0);
+    }
+}
+
+.avatar {
+    width: 120px;
+    height: 120px;
+    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
+    border-radius: 50%;
+    margin: 0 auto 30px;
+    display: flex;
+    justify-content: center;
+    align-items: center;
+    font-size: 60px;
+    color: white;
+    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.4);
+}
+
+h1 {
+    font-size: 42px;
+    color: #333;
+    margin-bottom: 15px;
+    font-weight: 700;
+}
+
+.welcome {
+    font-size: 24px;
+    color: #667eea;
+    margin-bottom: 25px;
+    font-weight: 500;
+}
+
+.message {
+    font-size: 16px;
+    color: #666;
+    line-height: 1.8;
+    margin-bottom: 30px;
+}
+
+.auth-buttons {
+    display: flex;
+    gap: 15px;
+    justify-content: center;
+    margin-bottom: 20px;
+}
+
+.btn {
+    display: inline-block;
+    padding: 12px 30px;
+    border-radius: 25px;
+    text-decoration: none;
+    font-size: 16px;
+    font-weight: 600;
+    cursor: pointer;
+    transition: all 0.3s ease;
+    border: none;
+}
+
+.btn-primary {
+    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
+    color: white;
+}
+
+.btn-primary:hover {
+    transform: translateY(-2px);
+    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.5);
+}
+
+.btn-secondary {
+    background: white;
+    color: #667eea;
+    border: 2px solid #667eea;
+}
+
+.btn-secondary:hover {
+    background: #667eea;
+    color: white;
+}
+
+.btn-danger {
+    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a5a 100%);
+    color: white;
+}
+
+.btn-danger:hover {
+    transform: translateY(-2px);
+    box-shadow: 0 5px 20px rgba(238, 90, 90, 0.5);
+}
+
+.btn-full {
+    width: 100%;
+}
+
+.footer {
+    font-size: 14px;
+    color: #999;
+    padding-top: 20px;
+    border-top: 1px solid #eee;
+    margin-top: 20px;
+}
+
+.footer span {
+    color: #667eea;
+    font-weight: 600;
+}
+
+.sparkle {
+    animation: sparkle 2s infinite;
+}
+
+@keyframes sparkle {
+    0%, 100% { opacity: 1; }
+    50% { opacity: 0.5; }
+}
+
+/* 表单样式 */
+.auth-container {
+    max-width: 400px;
+}
+
+.form-group {
+    margin-bottom: 20px;
+}
+
+.form-group input {
+    width: 100%;
+    padding: 15px 20px;
+    border: 2px solid #eee;
+    border-radius: 25px;
+    font-size: 16px;
+    transition: border-color 0.3s ease;
+    outline: none;
+}
+
+.form-group input:focus {
+    border-color: #667eea;
+}
+
+.auth-link {
+    margin-top: 20px;
+    color: #666;
+    font-size: 14px;
+}
+
+.auth-link a {
+    color: #667eea;
+    text-decoration: none;
+    font-weight: 600;
+}
+
+.auth-link a:hover {
+    text-decoration: underline;
+}
+
+/* 消息提示 */
+.flash-success {
+    background: #d4edda;
+    color: #155724;
+    padding: 12px 20px;
+    border-radius: 10px;
+    margin-bottom: 20px;
+    border: 1px solid #c3e6cb;
+}
+
+.flash-error {
+    background: #f8d7da;
+    color: #721c24;
+    padding: 12px 20px;
+    border-radius: 10px;
+    margin-bottom: 20px;
+    border: 1px solid #f5c6cb;
+}
+
+.flash-messages {
+    position: fixed;
+    top: 20px;
+    right: 20px;
+    z-index: 1000;
+}
+
+/* 响应式 */
+@media (max-width: 480px) {
+    .container {
+        padding: 40px 25px;
+    }
+    
+    h1 {
+        font-size: 32px;
+    }
+    
+    .welcome {
+        font-size: 20px;
+    }
+    
+    .auth-buttons {
+        flex-direction: column;
+    }
+    
+    .btn {
+        width: 100%;
+    }
+}