html,
body {
    margin: 0;
    padding: 0;
    width: 100%;
    overflow-x: hidden;
    background: #050816;
    color: white;
    font-family: Arial, Helvetica, sans-serif;
}

* {
    box-sizing: border-box;
}

.bookshelf-ai-landing {
    width: 100%;
    min-height: 100vh;
}

/* =====================================
   NAVBAR
===================================== */
.bookshelf-ai-navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 80px;
    display: flex;
    justify-content: center;
    background: rgba(5, 8, 22, 0.78);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    z-index: 1000;
}

.bookshelf-ai-navbar-inner {
    width: 100%;
    max-width: 1300px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 24px;
}

.bookshelf-ai-logo {
    font-size: 24px;
    font-weight: 700;
    letter-spacing: 0.5px;
}

.bookshelf-ai-navbar-links {
    display: flex;
    align-items: center;
    gap: 24px;
}

.bookshelf-ai-nav-link {
    color: #cbd5e1;
    text-decoration: none;
    font-size: 15px;
    transition: color 0.3s;
}

.bookshelf-ai-nav-link:hover {
    color: white;
}

.bookshelf-ai-navbar-btn {
    background: white;
    color: black;
    text-decoration: none;
    padding: 10px 20px;
    border-radius: 10px;
    font-size: 15px;
    font-weight: 700;
    transition: 0.3s;
    display: inline-block;
}

.bookshelf-ai-navbar-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(255, 255, 255, 0.15);
}

/* =====================================
   HERO SECTION
===================================== */
.bookshelf-ai-hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 140px 24px 80px 24px;
    text-align: center;
    background: radial-gradient(circle at top, rgba(59, 130, 246, 0.15), transparent 60%);
}

.bookshelf-ai-hero-content {
    width: 100%;
    max-width: 900px;
    margin: auto;
}

.bookshelf-ai-badge {
    display: inline-block;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.10);
    padding: 8px 16px;
    border-radius: 30px;
    margin-bottom: 24px;
    font-size: 13px;
    color: #94a3b8;
    letter-spacing: 0.5px;
}

.bookshelf-ai-hero-title {
    font-size: 4.5rem; /* Better fluid scale for desktops */
    line-height: 1.1;
    font-weight: 800;
    margin-top: 0;
    margin-bottom: 24px;
    letter-spacing: -1px;
}

.bookshelf-ai-hero-subtitle {
    max-width: 750px;
    margin: auto;
    color: #cbd5e1;
    font-size: 20px;
    line-height: 1.6;
}

.bookshelf-ai-hero-buttons {
    margin-top: 40px;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
}

.bookshelf-ai-primary-btn {
    background: white;
    color: black;
    text-decoration: none;
    padding: 14px 30px;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 700;
    transition: 0.3s;
    display: inline-block;
}

.bookshelf-ai-primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(255, 255, 255, 0.2);
}

.bookshelf-ai-secondary-btn {
    background: transparent;
    color: white;
    text-decoration: none;
    border: 1px solid rgba(255, 255, 255, 0.20);
    padding: 14px 30px;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    transition: 0.3s;
    display: inline-block;
}

.bookshelf-ai-secondary-btn:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(255, 255, 255, 0.4);
}

/* =====================================
   COMMON SECTION WIDTH
===================================== */
.bookshelf-ai-features-section,
.bookshelf-ai-preview-section,
.bookshelf-ai-trust-section,
.bookshelf-ai-cta-section {
    width: 100%;
    max-width: 1240px;
    margin: auto;
    padding-left: 24px;
    padding-right: 24px;
}

/* =====================================
   SECTION TITLES
===================================== */
.bookshelf-ai-section-title {
    text-align: center;
    font-size: 42px;
    font-weight: 700;
    margin-top: 0;
    margin-bottom: 48px;
    letter-spacing: -0.5px;
}

/* =====================================
   FEATURES
===================================== */
.bookshelf-ai-features-section {
    padding-top: 100px;
    padding-bottom: 100px;
}

.bookshelf-ai-features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
}

.bookshelf-ai-feature-card {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 20px;
    padding: 32px;
    transition: 0.3s ease;
}

.bookshelf-ai-feature-card:hover {
    transform: translateY(-4px);
    border-color: rgba(255, 255, 255, 0.15);
    background: rgba(255, 255, 255, 0.04);
}

.bookshelf-ai-feature-card h3 {
    font-size: 22px;
    margin-top: 0;
    margin-bottom: 14px;
    font-weight: 600;
}

.bookshelf-ai-feature-card p {
    color: #94a3b8;
    line-height: 1.6;
    font-size: 16px;
    margin: 0;
}

/* =====================================
   PREVIEW SECTION
===================================== */
.bookshelf-ai-preview-section {
    padding-top: 100px;
    padding-bottom: 100px;
    text-align: center;
}

.bookshelf-ai-preview-text {
    max-width: 700px;
    margin: -24px auto 48px auto;
    color: #cbd5e1;
    font-size: 18px;
    line-height: 1.6;
}

.bookshelf-ai-preview-card {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 24px;
    overflow: hidden;
    padding: 12px;
    max-width: 1000px;
    margin: 0 auto;
}

.bookshelf-ai-preview-image {
    width: 100%;
    height: auto;
    border-radius: 16px;
    display: block;
}

/* =====================================
   TRUST SECTION
===================================== */
.bookshelf-ai-trust-section {
    padding-top: 80px;
    padding-bottom: 100px;
}

.bookshelf-ai-trust-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}

.bookshelf-ai-trust-card {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: 20px;
    padding: 32px;
}

.bookshelf-ai-trust-card h3 {
    font-size: 20px;
    margin-top: 0;
    margin-bottom: 14px;
    font-weight: 600;
}

.bookshelf-ai-trust-card p {
    color: #94a3b8;
    line-height: 1.6;
    font-size: 15px;
    margin: 0;
}

/* =====================================
   CTA SECTION
===================================== */
.bookshelf-ai-cta-section {
    text-align: center;
    padding-top: 100px;
    padding-bottom: 140px;
}

.bookshelf-ai-cta-section h2 {
    font-size: 42px;
    font-weight: 800;
    margin-top: 0;
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.bookshelf-ai-cta-section p {
    max-width: 700px;
    margin: auto;
    color: #cbd5e1;
    font-size: 18px;
    line-height: 1.6;
}

/* =====================================
   FOOTER
===================================== */
.bookshelf-ai-footer {
    width: 100%;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    padding: 48px 24px;
    text-align: center;
}

.bookshelf-ai-footer-links {
    margin-bottom: 24px;
}

.bookshelf-ai-footer-links a {
    color: #64748b;
    text-decoration: none;
    margin: 0 12px;
    font-size: 14px;
    transition: 0.3s;
}

.bookshelf-ai-footer-links a:hover {
    color: white;
}

.bookshelf-ai-footer p {
    margin: 0;
    font-size: 14px;
}

/* =====================================
   RESPONSIVE DESIGN
===================================== */
@media(max-width: 768px) {
    .bookshelf-ai-navbar-inner {
        padding: 0 16px;
    }

    .bookshelf-ai-logo {
        font-size: 20px;
    }

    .bookshelf-ai-navbar-links {
        gap: 16px;
    }

    .bookshelf-ai-navbar-btn {
        padding: 8px 14px;
        font-size: 14px;
    }

    .bookshelf-ai-hero {
        padding-top: 120px;
    }

    .bookshelf-ai-hero-title {
        font-size: 40px;
    }

    .bookshelf-ai-hero-subtitle {
        font-size: 16px;
    }

    .bookshelf-ai-section-title {
        font-size: 30px;
        margin-bottom: 36px;
    }

    .bookshelf-ai-preview-text {
        font-size: 16px;
        margin-bottom: 32px;
    }

    .bookshelf-ai-feature-card,
    .bookshelf-ai-trust-card {
        padding: 24px;
    }

    .bookshelf-ai-cta-section h2 {
        font-size: 32px;
    }
    
    .bookshelf-ai-cta-section p {
        font-size: 16px;
    }
}