* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: Arial, sans-serif;
            background-color: #f5f5f5;
            height: 100vh;
            display: block;
            margin: 0;
            padding: 0;
        }

        header {
            background-color: #4CAF50;
            color: white;
            padding: 20px 0;
            text-align: center;
            font-size: 24px;
            font-weight: bold;
        }

        .form-container {
            background-color: #fff;
            padding: 30px;
            border-radius: 10px;
            box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
            width: 100%;
            max-width: 800px;
            margin: 30px auto; /* 폼을 가운데 정렬 */
        }

        h1 {
            text-align: center;
            margin-bottom: 20px;
            color: #4CAF50;
        }

        label {
            display: block;
            margin-bottom: 8px;
            font-weight: bold;
            color: #333;
        }

        input[type="email"], input[type="password"], input[type="text"], select {
            width: 100%;
            padding: 12px;
            margin-bottom: 20px;
            border: 1px solid #ddd;
            border-radius: 4px;
            font-size: 16px;
        }

        .error-message {
            color: red;
            font-size: 12px;
            margin-top: -15px;
            margin-bottom: 20px;
            display: none;
        }

        button { 
            padding: 12px;
            background-color: #4CAF50;
            color: white;
            border: none;
            border-radius: 4px;
            font-size: 16px;
            cursor: pointer;
        }
    
        .but {
            width: 100%;   
        }
        button:hover {
            background-color: #45a049;
        }

        .form-footer {
            text-align: center;
            margin-top: 15px;
        }

        .form-footer a {
            color: #4CAF50;
            text-decoration: none;
        }

        .form-footer a:hover {
            text-decoration: underline;
        }

        /* 반응형 디자인 */
        @media (max-width: 600px) {
            .form-container {
                padding: 20px;
            }

            input[type="email"], input[type="password"], input[type="text"], select {
                padding: 14px;
            }

            button {
                padding: 14px;
            } 
        }
        .footer {
            width: 100%;
            position: absolute; 
        }
        /* 모달 창 스타일 */
        .modal {
            display: none; /* 기본적으로 숨김 */
            position: fixed;
            z-index: 1000;
            left: 0;
            top: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(0, 0, 0, 0.9); /* 어두운 배경 */
            overflow: auto;
        }
        
        .modal-content {
            display: block;
            margin: auto;
            width: 90%;
            height: 80vh; /* 화면 높이의 80%까지 제한 */
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            border-radius: 8px;
            background: white;
            padding: 10px;
            
        }
        
        .close {
            position: absolute;
            top: 20px;
            right: 35px;
            color: #fff;
            font-size: 40px;
            font-weight: bold;
            transition: 0.3s;
            cursor: pointer;
        }
        
        .close:hover,
        .close:focus {
            color: #bbb;
            text-decoration: none;
        }