/* 现代化设计风格 - 渐变色彩与圆润设计 */

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #2d3748;
    position: relative;
    overflow-x: hidden;
}

/* 动态背景动画 */
.background-animation {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, #feca57);
    background-size: 400% 400%;
    animation: gradientShift 15s ease infinite;
    z-index: -1;
    opacity: 0.1;
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
    position: relative;
    z-index: 1;
}

.survey-form {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 24px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    animation: slideUp 0.8s ease-out;
}

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

/* 헤더 스타일 */
.header {
    text-align: center;
    margin-bottom: 50px;
    position: relative;
}

.icon {
    font-size: 4rem;
    margin-bottom: 20px;
    display: block;
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateY(0);
    }
    40% {
        transform: translateY(-10px);
    }
    60% {
        transform: translateY(-5px);
    }
}



.subtitle {
    font-size: 1.1rem;
    color: #718096;
    font-weight: 400;
}

/* 질문 카드 스타일 */
.question-card {
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
    border-radius: 20px;
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.5);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.question-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #ff6b6b, #4ecdc4, #45b7d1);
    border-radius: 20px 20px 0 0;
}

.question-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.question-header {
    display: flex;
    align-items: center;
    margin-bottom: 25px;
    gap: 15px;
}

.question-number {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 1.1rem;
    flex-shrink: 0;
}

h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: #2d3748;
    line-height: 1.5;
}

/* 옵션 그리드 */
.options-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 15px;
    margin-bottom: 25px;
}

.option-card {
    background: white;
    border: 2px solid #e2e8f0;
    border-radius: 16px;
    padding: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.option-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transition: left 0.5s ease;
}

.option-card:hover::before {
    left: 100%;
}

.option-card:hover {
    border-color: #667eea;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.15);
}

.option-card input[type="radio"] {
    display: none;
}

.option-card input[type="radio"]:checked + .option-content {
    color: #667eea;
}

.option-card input[type="radio"]:checked {
    background: linear-gradient(135deg, #667eea, #764ba2);
    border-color: #667eea;
}

.option-card:has(input[type="radio"]:checked) {
    background: linear-gradient(135deg, #f0f4ff, #e6f3ff);
    border-color: #667eea;
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.2);
}

.option-content {
    display: flex;
    align-items: center;
    gap: 12px;
    position: relative;
    z-index: 1;
}

.option-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.option-content span {
    font-weight: 500;
    font-size: 1rem;
    line-height: 1.4;
}

/* 简单文本输入 */
.text-input-modern {
    margin-top: 20px;
}

.text-input-modern input {
    width: 100%;
    padding: 16px 20px;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
    font-size: 1rem;
    background: white;
    transition: all 0.3s ease;
    outline: none;
}

.text-input-modern input:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* 제출 버튼 */
.submit-section {
    text-align: center;
    margin-top: 50px;
    padding-top: 40px;
    border-top: 1px solid #e2e8f0;
}

.submit-btn-modern {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 50px;
    padding: 18px 40px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 10px;
    transition: all 0.3s ease;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.3);
    position: relative;
    overflow: hidden;
}

.submit-btn-modern::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.submit-btn-modern:hover::before {
    left: 100%;
}

.submit-btn-modern:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.4);
}

.submit-btn-modern:active {
    transform: translateY(-1px);
}

.btn-icon {
    font-size: 1.2rem;
    animation: sparkle 2s infinite;
}

@keyframes sparkle {
    0%, 100% { transform: scale(1) rotate(0deg); }
    50% { transform: scale(1.1) rotate(180deg); }
}

/* 반응형 디자인 */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .survey-form {
        padding: 25px;
        border-radius: 20px;
    }
    
    h1 {
        font-size: 2.2rem;
    }
    
    .question-card {
        padding: 20px;
    }
    
    .options-grid {
        grid-template-columns: 1fr;
    }
    
    .option-card {
        padding: 15px;
    }
    
    .submit-btn-modern {
        padding: 15px 30px;
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .survey-form {
        padding: 20px;
    }
    
    h1 {
        font-size: 1.8rem;
    }
    
    .question-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
    
    .question-number {
        align-self: flex-start;
    }
    
    .option-content {
        flex-direction: column;
        text-align: center;
        gap: 8px;
    }
}

/* 스크롤바 스타일링 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f5f9;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(135deg, #667eea, #764ba2);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, #5a67d8, #6b46c1);
}

/* 로딩 애니메이션 */
@keyframes pulse {
    0% { opacity: 1; }
    50% { opacity: 0.5; }
    100% { opacity: 1; }
}

.loading {
    animation: pulse 1.5s infinite;
}