/* book.css - Table of Contents Layout */

.toc-container {
    max-width: 1200px;
    margin: 80px auto 40px;
    padding: 0 20px;
    width: 100%;
}

.toc-header {
    margin-bottom: 40px;
}

.toc-header h1 {
    font-size: 2.5rem;
    font-weight: 300;
    margin-bottom: 10px;
}

.toc-header h2 {
    font-size: 3rem;
    font-weight: 600;
    color: var(--accent-color);
}

.lessons-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.lesson-card {
    display: flex;
    flex-direction: column;
    padding: 30px;
    border-radius: 20px;
    text-decoration: none;
    color: #fff;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    min-height: 180px;
    justify-content: flex-end;
    position: relative;
    overflow: hidden;
}

.lesson-card:hover {
    transform: translateY(-5px) scale(1.02);
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
}

.lesson-card .emoji {
    font-size: 3rem;
    position: absolute;
    top: 20px;
    right: 20px;
    opacity: 0.8;
}

.lesson-num {
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 10px;
    opacity: 0.8;
    font-weight: 600;
}

.lesson-title {
    font-size: 1.8rem;
    font-weight: 700;
    line-height: 1.2;
}

/* Vibrant colors for cards */
.color-1 { background: linear-gradient(135deg, #FF9A9E 0%, #FECFEF 100%); color: #333; }
.color-2 { background: linear-gradient(135deg, #a18cd1 0%, #fbc2eb 100%); }
.color-3 { background: linear-gradient(135deg, #84fab0 0%, #8fd3f4 100%); color: #333; }
.color-4 { background: linear-gradient(135deg, #fccb90 0%, #d57eeb 100%); }
.color-5 { background: linear-gradient(135deg, #e0c3fc 0%, #8ec5fc 100%); color: #333; }
.color-6 { background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%); }
.color-7 { background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%); color: #333; }
.color-8 { background: linear-gradient(135deg, #fa709a 0%, #fee140 100%); }
.color-9 { background: linear-gradient(135deg, #30cfd0 0%, #330867 100%); }
.color-10 { background: linear-gradient(135deg, #a1c4fd 0%, #c2e9fb 100%); color: #333; }
.color-11 { background: linear-gradient(135deg, #ff0844 0%, #ffb199 100%); }
.color-12 { background: linear-gradient(135deg, #96fbc4 0%, #f9f586 100%); color: #333; }
.color-13 { background: linear-gradient(135deg, #2af598 0%, #009efd 100%); }

/* Responsive styles */
@media (max-width: 600px) {
    .toc-header h1 {
        font-size: 2rem;
    }
    .toc-header h2 {
        font-size: 2.2rem;
    }
    .lessons-grid {
        grid-template-columns: 1fr;
    }
    .lesson-card {
        min-height: 140px;
        padding: 20px;
    }
    .lesson-title {
        font-size: 1.5rem;
    }
    .lesson-card .emoji {
        font-size: 2.5rem;
    }
}