/* --- Variables & Reset --- */
:root {
    /* Palette */
    --primary: #FF6F61;       /* Vibrant Coral */
    --secondary: #FFD166;     /* Sunshine Yellow */
    --accent: #4D96FF;        /* Bright Blue */
    --bg-body: #F9FAFB;       /* Soft White/Grey */
    --bg-white: #FFFFFF;
    
    /* Typography */
    --text-dark: #2D3748;
    --text-light: #FFFFFF;
    --font-heading: 'Nunito', sans-serif;
    --font-body: 'Open Sans', sans-serif;
    
    /* Spacing & UI */
    --radius-pill: 50px;
    --radius-card: 16px;
    --shadow-soft: 0 10px 30px rgba(0, 0, 0, 0.05);
    --shadow-hover: 0 15px 35px rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: var(--font-body);
    background-color: var(--bg-body);
    color: var(--text-dark);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, .logo {
    font-family: var(--font-heading);
    font-weight: 800; /* Extra bold for friendly look */
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* --- Buttons --- */
.btn {
    display: inline-block;
    padding: 0.8rem 2.5rem;
    border-radius: var(--radius-pill);
    text-decoration: none;
    font-weight: 700;
    font-size: 1rem;
    border: none;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.15);
}

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

.btn-secondary {
    background-color: var(--text-dark);
    color: var(--secondary);
}

/* --- Navbar --- */
.navbar {
    background-color: var(--bg-white);
    padding: 1.2rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 15px rgba(0,0,0,0.03);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    color: var(--primary);
    text-decoration: none;
    letter-spacing: -0.5px;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 600;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--primary);
}

/* --- Hero Section --- */
.hero {
    background: linear-gradient(135deg, var(--primary) 0%, #FF8E85 100%);
    color: var(--text-light);
    text-align: center;
    padding: 6rem 0;
    position: relative;
    overflow: hidden;
}

.hero h1 {
    font-size: 3.5rem;
    line-height: 1.1;
    margin-bottom: 1rem;
}

.subhead {
    font-size: 1.25rem;
    margin-bottom: 2.5rem;
    opacity: 0.95;
    font-weight: 400;
}

/* --- Features Grid --- */
.features {
    padding: 5rem 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.feature-card {
    background: var(--bg-white);
    padding: 2.5rem 2rem;
    border-radius: var(--radius-card);
    text-align: center;
    box-shadow: var(--shadow-soft);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

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

.icon {
    font-size: 2.5rem;
    color: var(--accent);
    margin-bottom: 1.5rem;
}

.feature-card h3 {
    margin-bottom: 0.75rem;
    font-size: 1.25rem;
}

/* --- Newsletter Section --- */
.newsletter {
    background-color: var(--accent); /* Bright Blue Band */
    color: var(--text-light);
    text-align: center;
    padding: 4rem 0;
}

.newsletter h2 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.newsletter p {
    margin-bottom: 2rem;
    font-size: 1.1rem;
}

.newsletter-form input {
    padding: 0.8rem 1.5rem;
    border-radius: var(--radius-pill);
    border: none;
    width: 300px;
    margin-right: 0.5rem;
    font-family: var(--font-body);
}

/* --- Footer --- */
.footer {
    background-color: var(--bg-white);
    padding: 2rem 0;
    border-top: 1px solid #eee;
    font-size: 0.9rem;
    color: #666;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.social-links a {
    color: var(--text-dark);
    margin-left: 1rem;
    font-size: 1.1rem;
    transition: color 0.2s;
}

.social-links a:hover {
    color: var(--primary);
}

/* --- Responsiveness --- */
@media (max-width: 768px) {
    .nav-links {
        display: none; /* Hidden for simplicity on mobile view */
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr; /* Stack vertically */
    }
    
    .newsletter-form input {
        width: 100%;
        margin-bottom: 1rem;
        margin-right: 0;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    .social-links a {
        margin: 0 0.5rem;
    }
}

/* --- Page Header (Books Page) --- */
.page-header {
    background-color: #FFF5F5; /* Light tint of primary */
    padding: 4rem 0 2rem;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
}

/* --- Book Grid --- */
.books-section {
    padding: 4rem 0;
}

.book-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 2rem;
}

.book-card {
    background: var(--bg-white);
    border-radius: var(--radius-card);
    overflow: hidden;
    box-shadow: var(--shadow-soft);
    transition: transform 0.3s ease;
    display: flex;
    flex-direction: column;
}

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

.book-cover {
    height: 260px;
    background-color: #E2E8F0; /* Gray placeholder */
    display: flex;
    align-items: center;
    justify-content: center;
    color: #A0AEC0;
}

.book-details {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.book-details h3 {
    font-size: 1.2rem;
    margin-bottom: 0.25rem;
}

.book-subtitle {
    font-size: 0.9rem;
    color: #718096;
    margin-bottom: 0.75rem;
}

.price {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 1.2rem;
}

.book-details .btn {
    margin-top: auto;
    width: 100%;
    text-align: center;
}

/* --- Homepage New Sections --- */
.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--text-dark);
}

/* Activity Corner */
.activity-corner {
    background-color: #FFF9E6; /* Pale Yellow */
    padding: 5rem 0;
}

.activity-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.download-card {
    background: var(--bg-white);
    padding: 2.5rem;
    border-radius: var(--radius-card);
    text-align: center;
    box-shadow: var(--shadow-soft);
    border: 2px dashed var(--secondary);
}

.download-card p {
    margin-bottom: 1.5rem;
}

/* Trust & Promises */
.trust-badges {
    padding: 4rem 0;
    background-color: #f9f9f9;
    text-align: center;
}

.trust-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.trust-item i {
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: 1rem;
}

@media (max-width: 768px) {
    .activity-layout, .trust-grid {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
}

/* --- Utilities --- */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}