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

body {
    font-family: 'Noto Sans KR', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
    color: white;
}

header h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

header p {
    font-size: 1.2rem;
    opacity: 0.9;
}

main {
    background: white;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

.input-section {
    margin-bottom: 30px;
}

#textInput {
    width: 100%;
    padding: 20px;
    border: 2px solid #e1e5e9;
    border-radius: 15px;
    font-size: 16px;
    font-family: inherit;
    resize: vertical;
    transition: border-color 0.3s ease;
    background: #f8f9fa;
}

#textInput:focus {
    outline: none;
    border-color: #667eea;
    background: white;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.stats-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    padding: 25px;
    border-radius: 15px;
    text-align: center;
    border: 1px solid #dee2e6;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}

.stat-card h3 {
    color: #495057;
    font-size: 1rem;
    margin-bottom: 10px;
    font-weight: 500;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: #667eea;
    margin-bottom: 5px;
}

.stat-card p {
    color: #6c757d;
    font-size: 0.9rem;
}

.options-section {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 15px;
}

.option-group {
    display: flex;
    gap: 20px;
}

.checkbox-label {
    display: flex;
    align-items: center;
    cursor: pointer;
    font-weight: 500;
    color: #495057;
}

.checkbox-label input[type="checkbox"] {
    display: none;
}

.checkmark {
    width: 20px;
    height: 20px;
    background: white;
    border: 2px solid #dee2e6;
    border-radius: 4px;
    margin-right: 8px;
    position: relative;
    transition: all 0.3s ease;
}

.checkbox-label input[type="checkbox"]:checked + .checkmark {
    background: #667eea;
    border-color: #667eea;
}

.checkbox-label input[type="checkbox"]:checked + .checkmark::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    font-size: 12px;
    font-weight: bold;
}

.clear-btn {
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a52 100%);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 25px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.clear-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(255, 107, 107, 0.4);
}

.duplicate-section {
    background: linear-gradient(135deg, #fff3e0 0%, #ffe0b2 100%);
    padding: 25px;
    border-radius: 15px;
    border-left: 5px solid #ff9800;
    margin-bottom: 20px;
}

.duplicate-section h3 {
    color: #e65100;
    margin-bottom: 15px;
    font-size: 1.2rem;
}

.duplicate-words {
    min-height: 60px;
}

.no-duplicates {
    color: #666;
    font-style: italic;
    margin: 0;
}

.duplicate-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: white;
    padding: 10px 15px;
    margin: 8px 0;
    border-radius: 8px;
    border-left: 4px solid #ff9800;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.duplicate-word-group {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.duplicate-word {
    font-weight: 600;
    color: #e65100;
    font-size: 1rem;
}

.duplicate-words-list {
    font-size: 0.8rem;
    color: #666;
    font-style: italic;
}

.duplicate-count {
    background: #ff9800;
    color: white;
    padding: 4px 8px;
    border-radius: 12px;
    font-size: 0.8rem;
    font-weight: 600;
}

.info-section {
    background: linear-gradient(135deg, #e3f2fd 0%, #bbdefb 100%);
    padding: 25px;
    border-radius: 15px;
    border-left: 5px solid #2196f3;
}

.info-section h3 {
    color: #1976d2;
    margin-bottom: 15px;
    font-size: 1.2rem;
}

.info-section ul {
    list-style: none;
    padding-left: 0;
}

.info-section li {
    padding: 8px 0;
    color: #424242;
    position: relative;
    padding-left: 20px;
}

.info-section li::before {
    content: '•';
    color: #2196f3;
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* SEO 콘텐츠 섹션 */
.seo-content {
    margin: 40px 0;
    padding: 30px;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border-radius: 15px;
}

.seo-content h2 {
    color: #495057;
    font-size: 1.8rem;
    margin-bottom: 25px;
    text-align: center;
}

.seo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.seo-item {
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.seo-item:hover {
    transform: translateY(-3px);
}

.seo-item h3 {
    color: #667eea;
    font-size: 1.2rem;
    margin-bottom: 10px;
}

.seo-item p {
    color: #6c757d;
    line-height: 1.6;
}

/* FAQ 섹션 */
.faq-section {
    margin: 40px 0;
    padding: 30px;
    background: linear-gradient(135deg, #e8f5e8 0%, #d4edda 100%);
    border-radius: 15px;
    border-left: 5px solid #28a745;
}

.faq-section h2 {
    color: #155724;
    font-size: 1.8rem;
    margin-bottom: 25px;
    text-align: center;
}

.faq-item {
    background: white;
    padding: 20px;
    margin: 15px 0;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.faq-item h3 {
    color: #28a745;
    font-size: 1.1rem;
    margin-bottom: 10px;
}

.faq-item p {
    color: #6c757d;
    line-height: 1.6;
}

footer {
    text-align: center;
    color: white;
    opacity: 0.8;
    font-size: 0.9rem;
}

/* 반응형 디자인 */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    main {
        padding: 20px;
    }
    
    .stats-section {
        grid-template-columns: repeat(2, 1fr);
        gap: 15px;
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    .options-section {
        flex-direction: column;
        gap: 20px;
        align-items: stretch;
    }
    
    .option-group {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .stats-section {
        grid-template-columns: 1fr;
    }
    
    .option-group {
        flex-direction: column;
        gap: 10px;
    }
}

/* 애니메이션 효과 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.stat-card {
    animation: fadeIn 0.6s ease forwards;
}

.stat-card:nth-child(1) { animation-delay: 0.1s; }
.stat-card:nth-child(2) { animation-delay: 0.2s; }
.stat-card:nth-child(3) { animation-delay: 0.3s; }
.stat-card:nth-child(4) { animation-delay: 0.4s; }