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

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: #333;
    background: #f0f2f5; /* Couleur unie */
    min-height: 100vh;
}

.ebook-note {
    font-size: 0.9rem;
    color: #666;
    margin-top: -1rem;
    margin-bottom: 1rem;
    padding-left: 28px; /* Align with checkbox text */
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background: white;
    min-height: 100vh;
    box-shadow: 0 0 50px rgba(0, 0, 0, 0.1);
}

.header {
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 100%);
    color: white;
    padding: 4rem 2rem;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.header::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 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="75" cy="75" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="50" cy="10" r="0.5" fill="rgba(255,255,255,0.05)"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>');
    opacity: 0.3;
}

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

.main-title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
    animation: fadeInUp 1s ease-out;
}

.subtitle {
    font-size: 1.5rem;
    font-weight: 300;
    margin-bottom: 1rem;
    opacity: 0.9;
    animation: fadeInUp 1s ease-out 0.2s both;
}

.author {
    font-size: 1.2rem;
    font-weight: 500;
    opacity: 0.8;
    animation: fadeInUp 1s ease-out 0.4s both;
}

.main-content {
    padding: 3rem 2rem;
}

.book-section {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
    margin-bottom: 4rem;
    align-items: start;
}

.book-cover {
    position: sticky;
    top: 2rem;
}

.cover-image {
    width: 100%;
    max-width: 400px;
    height: auto;
    border-radius: 15px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.cover-image:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: 0 30px 60px rgba(0, 0, 0, 0.2);
}

.book-info h2 {
    color: #2c3e50;
    font-size: 1.8rem;
    margin-bottom: 1rem;
    font-weight: 600;
    position: relative;
}

.book-info h2::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 50px;
    height: 3px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    border-radius: 2px;
}

.book-info p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.7;
    color: #555;
}

.author-info {
    margin-bottom: 3rem;
}

.purchase-section {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    padding: 3rem;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.purchase-title {
    text-align: center;
    color: #2c3e50;
    font-size: 2.2rem;
    margin-bottom: 2rem;
    font-weight: 600;
}

.selection-container {
    max-width: 600px;
    margin: 0 auto;
}

.step {
    margin-bottom: 2rem;
    animation: fadeInUp 0.6s ease-out;
}

.step h3 {
    color: #2c3e50;
    font-size: 1.4rem;
    margin-bottom: 1rem;
    font-weight: 500;
}

.region-buttons,
.format-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.region-btn,
.format-btn {
    background: white;
    border: 2px solid #e9ecef;
    padding: 1.5rem;
    border-radius: 15px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
    font-weight: 500;
    color: #2c3e50;
}

.region-btn:hover,
.format-btn:hover {
    border-color: #667eea;
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.15);
}

.region-btn.selected,
.format-btn.selected {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    border-color: #667eea;
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.3);
}

.flag,
.icon {
    font-size: 2rem;
}

.checkbox-container {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    margin-bottom: 2rem;
    cursor: pointer;
    font-size: 1rem;
    line-height: 1.5;
}

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

.checkmark {
    width: 20px;
    height: 20px;
    border: 2px solid #ddd;
    border-radius: 4px;
    position: relative;
    transition: all 0.3s ease;
    flex-shrink: 0;
    margin-top: 2px;
}

.checkbox-container:hover .checkmark {
    border-color: #667eea;
}

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

.checkbox-container 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;
}

.conditions-link {
    color: #667eea;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.conditions-link:hover {
    color: #764ba2;
    text-decoration: underline;
}

.purchase-btn {
    width: 100%;
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    border: none;
    padding: 1.5rem 2rem;
    border-radius: 15px;
    font-size: 1.2rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    position: relative;
    overflow: hidden;
}

.purchase-btn::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;
}

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

.purchase-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 35px rgba(102, 126, 234, 0.4);
}

.purchase-btn:disabled {
    background: #ccc;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.purchase-btn:disabled::before {
    display: none;
}

.btn-icon {
    font-size: 1.5rem;
    transition: transform 0.3s ease;
}

.purchase-btn:hover .btn-icon {
    transform: translateX(5px);
}

.footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 2rem;
    margin-top: auto;
}

.footer-link {
    color: #667eea;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-link:hover {
    color: #764ba2;
}

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

@media (max-width: 768px) {
    .main-title {
        font-size: 2rem;
    }
    
    .subtitle {
        font-size: 1.2rem;
    }
    
    .book-section {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .book-cover {
        text-align: center;
        position: static;
    }
    
    .cover-image {
        max-width: 300px;
    }
    
    .region-buttons,
    .format-buttons {
        grid-template-columns: 1fr;
    }
    
    .main-content {
        padding: 2rem 1rem;
    }
    
    .purchase-section {
        padding: 2rem 1.5rem;
    }
}