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

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    color: #333;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.main-container {
    max-width: 500px;
    width: 100%;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    animation: slideIn 0.6s ease;
}

.header {
    background: linear-gradient(135deg, #4169E1 0%, #1E90FF 100%);
    color: white;
    padding: 30px;
    text-align: center;
    position: relative;
}

.header h1 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 10px;
}

.header p {
    font-size: 14px;
    opacity: 0.9;
}

.user-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 36px;
    color: white;
    margin: 0 auto 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
}

.form-container {
    padding: 40px;
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #495057;
    font-size: 14px;
}

.form-group input {
    width: 100%;
    padding: 16px 20px;
    border: 2px solid #e9ecef;
    border-radius: 12px;
    font-size: 16px;
    transition: all 0.3s ease;
    background: #fff;
    color: #333;
}

.form-group input:focus {
    outline: none;
    border-color: #4169E1;
    box-shadow: 0 0 0 3px rgba(65, 105, 225, 0.1);
}

.form-group input[readonly] {
    background: #f8f9fa;
    color: #6c757d;
    cursor: not-allowed;
}

.button-group {
    display: flex;
    gap: 15px;
    margin-top: 30px;
}

.btn {
    flex: 1;
    padding: 16px 24px;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
}

.btn-primary {
    background: linear-gradient(135deg, #4169E1 0%, #1E90FF 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(65, 105, 225, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(65, 105, 225, 0.4);
}

.btn-danger {
    background: linear-gradient(135deg, #dc3545 0%, #c82333 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(220, 53, 69, 0.3);
}

.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(220, 53, 69, 0.4);
}

.btn:active {
    transform: translateY(0);
}

.loading {
    pointer-events: none;
    opacity: 0.7;
}

.loading::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    margin: auto;
    border: 2px solid transparent;
    border-top-color: #ffffff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.info-card {
    background: #f8f9fa;
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 25px;
    border-left: 4px solid #4169E1;
}

.info-card h3 {
    font-size: 16px;
    color: #333;
    margin-bottom: 8px;
}

.info-card p {
    font-size: 14px;
    color: #666;
    line-height: 1.5;
}

.divider {
    height: 1px;
    background: #e9ecef;
    margin: 30px 0;
}

/* 반응형 */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }

    .main-container {
        margin: 10px;
        border-radius: 16px;
    }

    .form-container {
        padding: 30px 20px;
    }

    .header {
        padding: 25px 20px;
    }

    .header h1 {
        font-size: 24px;
    }

    .user-avatar {
        width: 60px;
        height: 60px;
        font-size: 28px;
        margin-bottom: 15px;
    }

    .button-group {
        flex-direction: column;
        gap: 12px;
    }
}

/* 성공/에러 메시지 */
.message {
    padding: 12px 16px;
    border-radius: 8px;
    margin-bottom: 20px;
    font-size: 14px;
    font-weight: 500;
}

.message.success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.message.error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* 입력 필드 포커스 효과 */
.form-group {
    position: relative;
}

.form-group input:focus + .focus-border {
    transform: scaleX(1);
}

.focus-border {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: #4169E1;
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

/* 로딩 상태 */
.btn.loading {
    position: relative;
    color: transparent;
}

.btn.loading::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    top: 50%;
    left: 50%;
    margin-left: -10px;
    margin-top: -10px;
    border: 2px solid transparent;
    border-top-color: #ffffff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}