/* ==========================================
   더 깊은 독서 - 온라인 독서토론 수업
   CSS Stylesheet
   ========================================== */

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Primary Colors - 신뢰감 있는 청색 계열 */
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --primary-light: #60a5fa;
    
    /* Secondary Colors - 따뜻한 주황 계열 */
    --secondary-color: #f59e0b;
    --secondary-dark: #d97706;
    --secondary-light: #fbbf24;
    
    /* Accent Colors */
    --accent-green: #10b981;
    --accent-red: #ef4444;
    --accent-purple: #8b5cf6;
    
    /* Neutral Colors */
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-500: #6b7280;
    --gray-700: #374151;
    --gray-900: #111827;
    
    /* Background & Text */
    --bg-color: #ffffff;
    --text-color: #1f2937;
    --text-light: #6b7280;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    
    /* Transitions */
    --transition: all 0.3s ease;
}

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    overflow-x: hidden;
}

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

/* ==========================================
   Hero Section
   ========================================== */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 80px 20px 100px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1440 320"><path fill="rgba(255,255,255,0.05)" d="M0,96L48,112C96,128,192,160,288,160C384,160,480,128,576,112C672,96,768,96,864,112C960,128,1056,160,1152,160C1248,160,1344,128,1392,112L1440,96L1440,320L1392,320C1344,320,1248,320,1152,320C1056,320,960,320,864,320C768,320,672,320,576,320C480,320,384,320,288,320C192,320,96,320,48,320L0,320Z"></path></svg>') no-repeat bottom;
    background-size: cover;
    opacity: 0.5;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.badge {
    display: inline-block;
    background: var(--secondary-color);
    color: white;
    padding: 8px 20px;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 20px;
    box-shadow: var(--shadow-lg);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.book-icon {
    font-size: 3rem;
    display: block;
    margin-bottom: 10px;
}

.hero-title {
    font-size: 3rem;
    font-weight: 900;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 500;
    margin-bottom: 20px;
    opacity: 0.95;
}

.hero-description {
    font-size: 1.2rem;
    margin-bottom: 40px;
    opacity: 0.9;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 40px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 16px 32px;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: var(--radius-lg);
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    box-shadow: var(--shadow-lg);
}

.btn-primary {
    background: var(--secondary-color);
    color: white;
}

.btn-primary:hover {
    background: var(--secondary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.btn-secondary {
    background: white;
    color: var(--primary-color);
}

.btn-secondary:hover {
    background: var(--gray-100);
    transform: translateY(-2px);
}

.hero-badge-list {
    display: flex;
    gap: 30px;
    justify-content: center;
    flex-wrap: wrap;
}

.badge-item {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1rem;
}

.badge-item i {
    color: var(--secondary-color);
    font-size: 1.2rem;
}

/* ==========================================
   Schedule Section
   ========================================== */
.schedule-section {
    padding: 60px 20px;
    background: var(--gray-50);
}

.schedule-box {
    background: white;
    border-radius: var(--radius-xl);
    padding: 40px;
    box-shadow: var(--shadow-lg);
    border: 3px solid var(--primary-color);
}

.schedule-box h3 {
    font-size: 1.8rem;
    color: var(--primary-color);
    margin-bottom: 30px;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

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

.schedule-item {
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--primary-color) 100%);
    color: white;
    padding: 25px;
    border-radius: var(--radius-lg);
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.schedule-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.schedule-item .day {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 10px;
}

.schedule-item .time {
    font-size: 1.1rem;
    margin-bottom: 8px;
}

.schedule-item .grade {
    font-size: 0.95rem;
    opacity: 0.9;
    background: rgba(255, 255, 255, 0.2);
    padding: 5px 10px;
    border-radius: 20px;
    display: inline-block;
    margin-top: 5px;
}

.schedule-note {
    text-align: center;
    color: var(--accent-red);
    font-weight: 600;
    font-size: 1rem;
}

/* ==========================================
   Section Common Styles
   ========================================== */
.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-number {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    width: 50px;
    height: 50px;
    line-height: 50px;
    border-radius: 50%;
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.section-title {
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 15px;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--text-light);
}

/* ==========================================
   Why Section
   ========================================== */
.why-section {
    padding: 80px 20px;
    background: white;
}

.comparison-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 40px;
}

.comparison-card {
    border-radius: var(--radius-xl);
    padding: 40px;
    box-shadow: var(--shadow-lg);
    transition: var(--transition);
}

.comparison-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.comparison-card.offline {
    background: linear-gradient(135deg, #fee2e2 0%, #fecaca 100%);
    border: 2px solid var(--accent-red);
}

.comparison-card.online {
    background: linear-gradient(135deg, #dbeafe 0%, #bfdbfe 100%);
    border: 2px solid var(--primary-color);
}

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

.card-header i {
    font-size: 2.5rem;
}

.comparison-card.offline .card-header i {
    color: var(--accent-red);
}

.comparison-card.online .card-header i {
    color: var(--primary-color);
}

.card-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
}

.comparison-list {
    list-style: none;
}

.comparison-list li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    margin-bottom: 18px;
    font-size: 1.05rem;
    line-height: 1.6;
}

.comparison-list i {
    font-size: 1.3rem;
    margin-top: 3px;
    flex-shrink: 0;
}

.comparison-card.offline .comparison-list i {
    color: var(--accent-red);
}

.comparison-card.online .comparison-list i {
    color: var(--accent-green);
}

/* ==========================================
   Process Section
   ========================================== */
.process-section {
    padding: 80px 20px;
    background: var(--gray-50);
}

.process-flow {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 20px;
}

.process-step {
    flex: 1;
    min-width: 200px;
    max-width: 250px;
    background: white;
    padding: 35px 25px;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    text-align: center;
    transition: var(--transition);
    position: relative;
}

.process-step:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.step-number {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.step-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--primary-color) 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
}

.step-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 12px;
}

.step-description {
    color: var(--text-light);
    font-size: 0.95rem;
    line-height: 1.6;
}

.process-arrow {
    color: var(--primary-color);
    font-size: 2rem;
    flex-shrink: 0;
}

/* ==========================================
   Media Section
   ========================================== */
.media-section {
    padding: 80px 20px;
    background: white;
}

.media-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 40px;
}

.media-card {
    background: var(--gray-50);
    border-radius: var(--radius-xl);
    padding: 40px;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.media-card:hover {
    box-shadow: var(--shadow-xl);
}

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

.media-header i {
    font-size: 2.5rem;
    color: var(--accent-red);
}

.media-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
}

.video-placeholder {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 60px 30px;
    border-radius: var(--radius-lg);
    text-align: center;
    margin-bottom: 20px;
    cursor: pointer;
    transition: var(--transition);
}

.video-placeholder:hover {
    transform: scale(1.02);
}

.video-placeholder i {
    font-size: 4rem;
    margin-bottom: 15px;
    opacity: 0.9;
}

.video-placeholder p {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.video-placeholder small {
    font-size: 0.9rem;
    opacity: 0.8;
}

.workbook-preview {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
}

.workbook-page {
    flex: 1;
    background: white;
    border-radius: var(--radius-md);
    padding: 20px;
    box-shadow: var(--shadow-sm);
}

.page-header {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--primary-light);
}

.page-content {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.activity-item {
    font-size: 0.95rem;
    color: var(--text-color);
    padding: 8px;
    background: var(--gray-50);
    border-radius: var(--radius-sm);
}

.media-description {
    color: var(--text-light);
    line-height: 1.7;
}

/* ==========================================
   FAQ Section
   ========================================== */
.faq-section {
    padding: 80px 20px;
    background: var(--gray-50);
}

.faq-content {
    max-width: 1000px;
    margin: 0 auto;
}

.expertise-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 30px;
}

.expertise-card {
    background: white;
    padding: 35px 25px;
    border-radius: var(--radius-xl);
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.expertise-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-xl);
}

.expertise-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, var(--secondary-light) 0%, var(--secondary-color) 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
}

.expertise-card h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--gray-900);
}

.expertise-card p {
    color: var(--text-light);
    line-height: 1.7;
}

/* ==========================================
   Offer Section
   ========================================== */
.offer-section {
    padding: 80px 20px;
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
    color: white;
}

.offer-box {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.offer-badge {
    display: inline-block;
    background: var(--accent-red);
    color: white;
    padding: 10px 25px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 25px;
    animation: bounce 1s infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.offer-title {
    font-size: 2.5rem;
    font-weight: 900;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
}

.offer-title .highlight {
    color: #fef3c7;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.offer-description {
    font-size: 1.2rem;
    margin-bottom: 40px;
    line-height: 1.8;
    opacity: 0.95;
}

.price-box {
    background: rgba(255, 255, 255, 0.2);
    padding: 30px;
    border-radius: var(--radius-xl);
    margin-bottom: 20px;
    backdrop-filter: blur(10px);
}

.original-price {
    font-size: 1.2rem;
    text-decoration: line-through;
    opacity: 0.8;
    margin-bottom: 15px;
}

.discount-price {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
}

.discount-price .arrow {
    font-size: 2rem;
}

.discount-price .amount {
    font-size: 3rem;
    font-weight: 900;
}

.discount-price .period {
    font-size: 1.5rem;
}

.offer-note {
    font-size: 1rem;
    opacity: 0.9;
}

/* ==========================================
   Application Section
   ========================================== */
.application-section {
    padding: 80px 20px;
    background: white;
}

.application-form-wrapper {
    max-width: 800px;
    margin: 0 auto;
}

.application-form {
    background: var(--gray-50);
    padding: 50px;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
    margin-bottom: 25px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group.full-width {
    grid-column: 1 / -1;
}

.form-group label {
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.form-group label i {
    color: var(--primary-color);
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: 14px 18px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: 'Noto Sans KR', sans-serif;
    transition: var(--transition);
    background: white;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.checkbox-group {
    margin-top: 10px;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    font-weight: 500;
}

.checkbox-label input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
}

.submit-btn {
    width: 100%;
    background: var(--primary-color);
    color: white;
    padding: 18px;
    font-size: 1.2rem;
    font-weight: 700;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    box-shadow: var(--shadow-md);
    margin-top: 15px;
}

.submit-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.form-success {
    background: white;
    padding: 60px 40px;
    border-radius: var(--radius-xl);
    text-align: center;
    box-shadow: var(--shadow-lg);
}

.success-icon {
    font-size: 5rem;
    color: var(--accent-green);
    margin-bottom: 20px;
}

.form-success h3 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 15px;
}

.form-success p {
    font-size: 1.1rem;
    color: var(--text-light);
    line-height: 1.8;
}

/* ==========================================
   Contact Section
   ========================================== */
.contact-section {
    padding: 60px 20px;
    background: var(--gray-50);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    max-width: 1000px;
    margin: 0 auto;
}

.contact-card {
    background: white;
    padding: 35px 25px;
    border-radius: var(--radius-xl);
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.contact-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.contact-card i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.contact-card h3 {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--gray-900);
}

.contact-card p {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.contact-card small {
    font-size: 0.9rem;
    color: var(--text-light);
}

/* ==========================================
   Footer
   ========================================== */
.footer {
    background: var(--gray-900);
    color: white;
    padding: 50px 20px;
    text-align: center;
}

.footer-content {
    max-width: 800px;
    margin: 0 auto;
}

.footer-logo h3 {
    font-size: 1.8rem;
    margin-bottom: 10px;
}

.footer-logo p {
    font-size: 1.1rem;
    opacity: 0.8;
    margin-bottom: 30px;
}

.footer-info p {
    font-size: 0.95rem;
    opacity: 0.7;
    margin-bottom: 8px;
}

/* ==========================================
   Floating Button
   ========================================== */
.floating-btn {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: var(--secondary-color);
    color: white;
    width: 70px;
    height: 70px;
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 3px;
    text-decoration: none;
    box-shadow: var(--shadow-xl);
    transition: var(--transition);
    z-index: 1000;
}

.floating-btn:hover {
    transform: scale(1.1);
    background: var(--secondary-dark);
}

.floating-btn i {
    font-size: 1.5rem;
}

.floating-btn span {
    font-size: 0.75rem;
    font-weight: 600;
}

/* ==========================================
   Back to Top Button
   ========================================== */
.back-to-top {
    position: fixed;
    bottom: 120px;
    right: 30px;
    background: var(--primary-color);
    color: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    border: none;
    display: none;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--shadow-lg);
    transition: var(--transition);
    z-index: 1000;
}

.back-to-top.show {
    display: flex;
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
}

.back-to-top i {
    font-size: 1.3rem;
}

/* ==========================================
   Responsive Design
   ========================================== */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.2rem;
    }
    
    .hero-subtitle {
        font-size: 1.2rem;
    }
    
    .hero-description {
        font-size: 1rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: 15px;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .hero-badge-list {
        flex-direction: column;
        gap: 15px;
    }
    
    .schedule-box {
        padding: 25px;
    }
    
    .schedule-box h3 {
        font-size: 1.4rem;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .process-arrow {
        transform: rotate(90deg);
    }
    
    .workbook-preview {
        flex-direction: column;
    }
    
    .offer-title {
        font-size: 1.8rem;
    }
    
    .discount-price .amount {
        font-size: 2.2rem;
    }
    
    .application-form {
        padding: 30px 20px;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .floating-btn {
        width: 60px;
        height: 60px;
        bottom: 20px;
        right: 20px;
    }
    
    .floating-btn i {
        font-size: 1.3rem;
    }
    
    .floating-btn span {
        font-size: 0.7rem;
    }
    
    .back-to-top {
        bottom: 95px;
        right: 20px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 60px 15px 80px;
    }
    
    .hero-title {
        font-size: 1.8rem;
    }
    
    .book-icon {
        font-size: 2.5rem;
    }
    
    .comparison-card,
    .media-card,
    .expertise-card {
        padding: 25px;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .offer-title {
        font-size: 1.5rem;
    }
}