<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Classs Robotics — Robotics &amp; AI Summer Camp</title>
    <link rel="preconnect" href="https://fonts.googleapis.com">
    <link href="https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=Space+Grotesk:wght@400;500;600;700&display=swap" rel="stylesheet">
    <style>
/* ================================================
   CLASSS ROBOTICS — Global Styles
   ================================================ */
:root {
    --primary: #e8a527;
    --primary-dark: #c48a1a;
    --dark: #0b1e3d;
    --dark2: #122a50;
    --dark3: #1a3565;
    --white: #ffffff;
    --light: #f4f7fc;
    --gray: #6b7c93;
    --gray-light: #dce3ed;
    --radius: 12px;
    --radius-lg: 20px;
    --shadow: 0 4px 24px rgba(0,0,0,0.08);
    --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
    --transition: 0.3s cubic-bezier(.4,0,.2,1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body { font-family: 'Inter', sans-serif; color: #333; background: var(--white); line-height: 1.6; overflow-x: hidden; }
img { max-width: 100%; height: auto; display: block; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: 100px 0; }
.center { text-align: center; }

.section-tag {
    display: inline-block;
    font-size: 14px; font-weight: 600; text-transform: uppercase;
    letter-spacing: 3px; color: var(--primary);
    margin-bottom: 12px;
}
.section-title {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 42px; font-weight: 700; line-height: 1.2;
    color: var(--dark); margin-bottom: 20px;
}
.section-title span { color: var(--primary); }
.section-subtitle {
    font-size: 17px; color: var(--gray); max-width: 600px; margin: 0 auto 50px;
    text-align: center;
}

.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 14px 32px; border-radius: 8px; font-weight: 600;
    font-size: 15px; transition: var(--transition); cursor: pointer;
    border: none; letter-spacing: 0.3px;
}
.btn-primary { background: var(--primary); color: var(--white); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(232,165,39,0.35); }
.btn-outline { border: 2px solid rgba(255,255,255,0.4); color: var(--white); background: transparent; }
.btn-outline:hover { background: rgba(255,255,255,0.1); border-color: var(--white); }
.btn-full { width: 100%; }

.navbar {
    position: fixed; top: 0; left: 0; width: 100%; z-index: 1000;
    padding: 18px 0; transition: var(--transition);
}
.navbar.scrolled {
    background: rgba(11,30,61,0.97); backdrop-filter: blur(12px);
    padding: 12px 0; box-shadow: 0 2px 20px rgba(0,0,0,0.15);
}
.nav-container {
    max-width: 1200px; margin: 0 auto; padding: 0 24px;
    display: flex; align-items: center; justify-content: space-between;
}
.nav-logo { display: flex; align-items: center; gap: 14px; }
.logo-icon {
    width: 80px;
    height: 80px;
    object-fit: contain;
    filter: brightness(1.1) contrast(1.1);
}
.logo-text {
    font-family: 'Space Grotesk', sans-serif; font-size: 20px;
    font-weight: 700; color: var(--white); letter-spacing: 2px;
}
.logo-text span { color: var(--primary); }
.nav-links { display: flex; gap: 32px; }
.nav-links a {
    color: rgba(255,255,255,0.8); font-size: 14px; font-weight: 500;
    transition: var(--transition); position: relative;
}
.nav-links a:hover { color: var(--primary); }
.nav-links a::after {
    content: ''; position: absolute; bottom: -4px; left: 0; width: 0;
    height: 2px; background: var(--primary); transition: var(--transition);
}
.nav-links a:hover::after { width: 100%; }
.nav-cta {
    padding: 10px 24px; background: var(--primary); color: var(--white);
    border-radius: 8px; font-size: 14px; font-weight: 600;
    transition: var(--transition);
}
.nav-cta:hover { background: var(--primary-dark); transform: translateY(-1px); }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 4px; }
.nav-toggle span {
    display: block; width: 26px; height: 3px; background: var(--white);
    border-radius: 3px; margin: 5px 0; transition: var(--transition);
}
.nav-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px,6px); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px,-6px); }

.hero {
    position: relative; min-height: 100vh; display: flex; align-items: center;
    background: url('assets/images/hero-tech.jpeg') center/cover no-repeat;
    overflow: hidden;
}
.hero-overlay {
    position: absolute; inset: 0;
    background: linear-gradient(135deg, rgba(11,30,61,0.82) 0%, rgba(18,42,80,0.75) 50%, rgba(26,53,101,0.7) 100%);
}
.hero-content {
    position: relative; z-index: 2; max-width: 1200px; margin: 0 auto;
    padding: 120px 24px 80px; display: grid;
    grid-template-columns: 1fr 1fr; gap: 60px; align-items: center;
}
.hero-badge {
    display: inline-block; background: rgba(232,165,39,0.15);
    border: 1px solid rgba(232,165,39,0.3); color: var(--primary);
    padding: 8px 20px; border-radius: 50px; font-size: 14px;
    font-weight: 600; margin-bottom: 24px;
}
.hero-title {
    font-family: 'Space Grotesk', sans-serif; font-size: 62px;
    font-weight: 800; color: var(--white); line-height: 1.1;
    margin-bottom: 24px;
}
.hero-title .highlight { color: var(--primary); }
.hero-sub {
    font-size: 18px; color: rgba(255,255,255,0.65); line-height: 1.7;
    margin-bottom: 36px; max-width: 500px;
}
.hero-buttons { display: flex; gap: 16px; margin-bottom: 48px; }
.hero-stats { display: flex; gap: 40px; }
.hero-stat { display: flex; flex-direction: column; }
.hero-stat strong { font-size: 28px; color: var(--primary); font-weight: 800; }
.hero-stat span { font-size: 13px; color: rgba(255,255,255,0.5); }
.hero-image { position: relative; }
.hero-image img {
    border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
    width: 100%; height: 480px; object-fit: cover;
}

.hero-contact-card {
    position: absolute; top: 280px; left: 0; z-index: 10;
    background: linear-gradient(135deg, rgba(232,165,39,0.98) 0%, rgba(232,165,39,0.95) 100%);
    backdrop-filter: blur(20px);
    border-radius: 0 20px 20px 0; padding: 28px 32px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.25), 0 0 0 1px rgba(232,165,39,0.2);
    min-width: 280px;
    max-width: 320px;
    height: 300px;
    border: 3px solid transparent;
    background-clip: padding-box;
    animation: slideInLeft 0.6s ease-out;
}
.hero-contact-card::before {
    content: '';
    position: absolute;
    top: -3px; right: -3px; bottom: -3px; left: -3px;
    background: linear-gradient(135deg, var(--primary) 0%, #f4b942 100%);
    border-radius: 20px;
    z-index: -1;
}
.hero-contact-card h3 {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 20px; color: var(--dark); margin-bottom: 20px;
    text-align: center; font-weight: 700;
    display: flex; align-items: center; justify-content: center; gap: 8px;
}
.hero-contact-item {
    display: flex; align-items: center; gap: 14px;
    padding: 16px; margin-bottom: 12px;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    border-radius: 12px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid rgba(232,165,39,0.1);
    position: relative;
    overflow: hidden;
}
.hero-contact-item::before {
    content: '';
    position: absolute;
    top: 0; left: -100%; width: 100%; height: 100%;
    background: linear-gradient(90deg, transparent, rgba(232,165,39,0.1), transparent);
    transition: left 0.5s;
}
.hero-contact-item:hover::before {
    left: 100%;
}
.hero-contact-item:hover {
    background: linear-gradient(135deg, rgba(232,165,39,0.08) 0%, rgba(232,165,39,0.05) 100%);
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(232,165,39,0.2);
    border-color: var(--primary);
}
.hero-contact-item:last-child {
    margin-bottom: 0;
}
.hero-contact-icon {
    font-size: 24px; width: 50px; height: 50px;
    display: flex; align-items: center; justify-content: center;
    background: linear-gradient(135deg, var(--primary) 0%, #f4b942 100%);
    border-radius: 12px;
    flex-shrink: 0;
    box-shadow: 0 4px 12px rgba(232,165,39,0.3);
}
.hero-contact-text {
    display: flex; flex-direction: column; gap: 4px;
}
.hero-contact-text strong {
    font-size: 11px; color: var(--gray);
    font-weight: 700; text-transform: uppercase;
    letter-spacing: 1px;
}
.hero-contact-text span {
    font-size: 15px; color: var(--dark);
    font-weight: 600;
    font-family: 'Space Grotesk', sans-serif;
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.about { background: var(--light); }
.about-grid {
    display: grid; grid-template-columns: 1fr 1fr;
    gap: 60px; align-items: center;
}
.about-images { position: relative; height: 500px; }
.about-img {
    border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
    object-fit: cover; position: absolute;
}
.about-img-1 { width: 320px; height: 380px; top: 0; left: 0; z-index: 2; }
.about-img-2 {
    width: 280px; height: 320px; bottom: 0; right: 0;
    border: 5px solid var(--white);
}
.about-desc { font-size: 16px; color: var(--gray); line-height: 1.8; margin-bottom: 32px; }
.about-features { display: flex; flex-direction: column; gap: 20px; }
.about-feature {
    display: flex; gap: 16px; align-items: flex-start;
    padding: 16px; border-radius: var(--radius); background: var(--white);
    box-shadow: var(--shadow); transition: var(--transition);
    opacity: 0; transform: translateY(20px);
}
.about-feature.visible { opacity: 1; transform: translateY(0); }
.af-icon {
    font-size: 28px; flex-shrink: 0; width: 50px; height: 50px;
    display: flex; align-items: center; justify-content: center;
    background: rgba(232,165,39,0.1); border-radius: 10px;
}
.about-feature strong { font-size: 15px; color: var(--dark); display: block; margin-bottom: 4px; }
.about-feature p { font-size: 13px; color: var(--gray); margin: 0; }

.programs { background: var(--white); }
.programs-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; }
.program-card {
    border-radius: var(--radius-lg); overflow: hidden;
    background: var(--white); box-shadow: var(--shadow);
    transition: var(--transition); position: relative;
    opacity: 0; transform: translateY(30px);
}
.program-card.visible { opacity: 1; transform: translateY(0); }
.program-card:hover { transform: translateY(-8px); box-shadow: var(--shadow-lg); }
.program-card.featured { border: 2px solid var(--primary); }
.program-badge {
    position: absolute; top: 16px; left: 16px; z-index: 3;
    background: var(--primary); color: var(--white);
    padding: 6px 16px; border-radius: 50px; font-size: 12px;
    font-weight: 700; text-transform: uppercase; letter-spacing: 1px;
}
.program-img { width: 100%; height: 240px; object-fit: cover; }
.program-body { padding: 28px; }
.program-body h3 {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 22px; font-weight: 700; color: var(--dark); margin-bottom: 6px;
}
.program-age { font-size: 14px; color: var(--primary); font-weight: 600; margin-bottom: 20px; }
.program-list { margin-bottom: 24px; }
.program-list li {
    padding: 8px 0; font-size: 14px; color: var(--gray);
    border-bottom: 1px solid var(--gray-light);
    padding-left: 24px; position: relative;
}
.program-list li::before {
    content: '✓'; position: absolute; left: 0; color: var(--primary); font-weight: 700;
}

.curriculum-section { background: var(--dark); }
.curriculum-section .section-tag { color: var(--primary); }
.curriculum-section .section-title { color: var(--white); }
.curriculum-section .section-title span { color: var(--primary); }
.curriculum-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.curr-card {
    background: rgba(255,255,255,0.06); border: 1px solid rgba(255,255,255,0.1);
    border-radius: var(--radius-lg); padding: 32px; transition: var(--transition);
    opacity: 0; transform: translateY(20px);
}
.curr-card.visible { opacity: 1; transform: translateY(0); }
.curr-card:hover {
    background: rgba(255,255,255,0.1); transform: translateY(-4px);
    border-color: var(--primary);
}
.curr-num {
    font-family: 'Space Grotesk', sans-serif; font-size: 42px;
    font-weight: 700; color: var(--primary); opacity: 0.4; margin-bottom: 12px;
}
.curr-card h4 {
    font-size: 18px; color: var(--white); margin-bottom: 12px;
    font-family: 'Space Grotesk', sans-serif;
}
.curr-card p { font-size: 14px; color: rgba(255,255,255,0.55); line-height: 1.7; }

.why-us { background: var(--light); }
.why-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; margin-top: 50px; }
.why-card {
    background: var(--white); border-radius: var(--radius-lg); padding: 36px 28px;
    text-align: center; box-shadow: var(--shadow); transition: var(--transition);
    opacity: 0; transform: translateY(20px);
}
.why-card.visible { opacity: 1; transform: translateY(0); }
.why-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.why-icon {
    font-size: 40px; width: 72px; height: 72px; margin: 0 auto 16px;
    display: flex; align-items: center; justify-content: center;
    background: rgba(232,165,39,0.1); border-radius: 16px;
}
.why-card h4 {
    font-family: 'Space Grotesk', sans-serif; font-size: 17px;
    color: var(--dark); margin-bottom: 10px;
}
.why-card p { font-size: 14px; color: var(--gray); line-height: 1.6; }

.pdf-downloads {
    display: flex; gap: 20px; justify-content: center; align-items: center;
    margin: 30px auto 50px; flex-wrap: wrap;
}
.pdf-download-link {
    display: inline-flex; align-items: center; gap: 10px;
    padding: 14px 24px; background: var(--primary); color: var(--white);
    border-radius: 10px; font-size: 15px; font-weight: 600;
    transition: var(--transition); box-shadow: var(--shadow);
    border: 2px solid var(--primary);
}
.pdf-download-link:hover {
    background: var(--primary-dark); transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(232,165,39,0.4);
}
.pdf-icon {
    font-size: 24px; display: flex; align-items: center;
}

.contact { background: var(--dark); }
.contact .section-tag { color: var(--primary); }
.contact .section-title { color: var(--white); }
.contact .section-title span { color: var(--primary); }
.contact-grid {
    display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: start;
}
.contact-desc { font-size: 16px; color: rgba(255,255,255,0.6); line-height: 1.8; margin-bottom: 32px; }
.contact-details { display: flex; flex-direction: column; gap: 20px; }
.cd-item { display: flex; gap: 16px; align-items: flex-start; }
.cd-icon {
    font-size: 24px; width: 48px; height: 48px; flex-shrink: 0;
    display: flex; align-items: center; justify-content: center;
    background: rgba(232,165,39,0.12); border-radius: 12px;
}
.cd-item strong { font-size: 14px; color: var(--white); display: block; margin-bottom: 2px; }
.cd-item p { font-size: 13px; color: rgba(255,255,255,0.5); margin: 0; }
.contact-form {
    background: #ffffff; border: 1px solid rgba(0,0,0,0.1);
    border-radius: var(--radius-lg); padding: 36px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.1);
}
.contact-form h3 {
    font-family: 'Space Grotesk', sans-serif; font-size: 22px;
    color: #1a1a2e; margin-bottom: 24px;
}
.contact-form input,
.contact-form select,
.contact-form textarea {
    width: 100%; padding: 14px 16px; border-radius: 8px;
    border: 1px solid #d1d5db; background: #f9fafb;
    color: #1a1a2e; font-size: 14px; font-family: 'Inter', sans-serif;
    margin-bottom: 14px; transition: var(--transition); outline: none;
}
.contact-form input::placeholder,
.contact-form textarea::placeholder { color: #9ca3af; }
.contact-form select { color: #9ca3af; }
.contact-form select option { background: #ffffff; color: #1a1a2e; }
.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus { border-color: var(--primary); background: #ffffff; box-shadow: 0 0 0 3px rgba(232,165,39,0.15); }

.radio-group {
    margin-bottom: 14px;
}
.radio-label-title {
    display: block;
    color: #1a1a2e;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 12px;
}
.radio-option {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 16px;
    margin-bottom: 8px;
    background: #f9fafb;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}
.radio-option:hover {
    background: #fef9ee;
    border-color: var(--primary);
}
.radio-option input[type="radio"],
.radio-option input[type="checkbox"] {
    width: 18px;
    height: 18px;
    margin: 0;
    cursor: pointer;
    accent-color: var(--primary);
}
.radio-option span {
    color: #374151;
    font-size: 14px;
    flex: 1;
}
.radio-option input[type="radio"]:checked + span,
.radio-option input[type="checkbox"]:checked + span {
    color: #b45309;
    font-weight: 600;
}

/* Success Modal */
.success-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(10px);
    z-index: 10000;
    justify-content: center;
    align-items: center;
    animation: fadeIn 0.3s ease;
}
.success-modal.active {
    display: flex;
}
.modal-content {
    background: linear-gradient(135deg, #0b1e3d 0%, #1a3565 100%);
    border-radius: 20px;
    padding: 50px 40px;
    max-width: 500px;
    width: 90%;
    text-align: center;
    position: relative;
    border: 2px solid rgba(232, 165, 39, 0.3);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    animation: slideUp 0.4s ease;
}
.modal-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--primary) 0%, #f4b942 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
    font-size: 40px;
    animation: scaleIn 0.5s ease 0.2s both;
}
.modal-title {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 28px;
    font-weight: 700;
    color: var(--white);
    margin-bottom: 16px;
}
.modal-message {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.6;
    margin-bottom: 32px;
}
.modal-close-btn {
    background: linear-gradient(135deg, var(--primary) 0%, #f4b942 100%);
    color: var(--dark);
    border: none;
    padding: 14px 36px;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    font-family: 'Inter', sans-serif;
}
.modal-close-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(232, 165, 39, 0.4);
}
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}
@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}
@keyframes scaleIn {
    from {
        transform: scale(0);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

.footer { background: #071428; padding: 60px 0 0; }
.footer-grid {
    display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px;
    padding-bottom: 40px; border-bottom: 1px solid rgba(255,255,255,0.08);
}
.footer-brand h3 {
    font-family: 'Space Grotesk', sans-serif; font-size: 20px;
    color: var(--white); margin-bottom: 14px;
}
.footer-brand h3 span { color: var(--primary); }
.footer-brand p { font-size: 14px; color: rgba(255,255,255,0.45); line-height: 1.7; }
.footer-links h4 {
    font-size: 15px; color: var(--white); margin-bottom: 18px;
    font-family: 'Space Grotesk', sans-serif;
}
.footer-links a {
    display: block; font-size: 14px; color: rgba(255,255,255,0.45);
    padding: 5px 0; transition: var(--transition);
}
.footer-links a:hover { color: var(--primary); padding-left: 4px; }
.footer-bottom { text-align: center; padding: 24px 0; }
.footer-bottom p { font-size: 13px; color: rgba(255,255,255,0.3); }

@media (max-width: 1024px) {
    .hero-content { grid-template-columns: 1fr; text-align: center; gap: 40px; }
    .hero-sub { margin: 0 auto 36px; }
    .hero-buttons { justify-content: center; }
    .hero-stats { justify-content: center; }
    .hero-image img { height: 360px; }
    .about-grid { grid-template-columns: 1fr; gap: 40px; }
    .about-images { height: 380px; display: flex; gap: 16px; justify-content: center; }
    .about-img { position: relative; }
    .about-img-1 { width: 50%; height: 360px; }
    .about-img-2 { width: 50%; height: 360px; }
    .curriculum-grid { grid-template-columns: repeat(2, 1fr); }
    .why-grid { grid-template-columns: repeat(2, 1fr); }
    .contact-grid { grid-template-columns: 1fr; gap: 40px; }
    .footer-grid { grid-template-columns: 1fr 1fr; gap: 30px; }
    .hero-contact-card {
        right: 20px; top: 100px; min-width: 260px; padding: 24px;
    }
    .hero-contact-card h3 { font-size: 18px; }
    .hero-contact-text span { font-size: 14px; }
}

@media (max-width: 768px) {
    .section { padding: 70px 0; }
    .section-title { font-size: 32px; }
    .logo-icon { width: 70px; height: 70px; }
    .logo-text { font-size: 18px; }
    .nav-links {
        display: none; flex-direction: column; position: absolute;
        top: 100%; left: 0; width: 100%; background: var(--dark);
        padding: 20px 24px; gap: 16px;
        box-shadow: 0 8px 24px rgba(0,0,0,0.2);
    }
    .nav-links.active { display: flex; }
    .nav-cta { display: none; }
    .nav-toggle { display: block; }
    .hero { min-height: auto; position: relative; }
    .hero-content {
        padding: 80px 24px 40px;
        display: flex;
        flex-direction: column;
    }
    .hero-text { order: 1; }
    .hero-image { order: 3; margin-top: 30px; }
    .hero-title { font-size: 40px; }
    .hero-stats { gap: 24px; }
    .hero-stat strong { font-size: 22px; }
    .programs-grid { grid-template-columns: 1fr; }
    .curriculum-grid { grid-template-columns: 1fr; }
    .why-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    .pdf-downloads { flex-direction: column; gap: 12px; }
    .pdf-download-link { width: 100%; max-width: 320px; justify-content: center; }
    .hero-contact-card {
        display: none;
    }
    .hero-contact-card h3 { font-size: 17px; margin-bottom: 16px; }
    .hero-contact-item { padding: 14px 12px; gap: 12px; }
    .hero-contact-icon { width: 45px; height: 45px; font-size: 22px; }
    .hero-contact-text strong { font-size: 10px; }
    .hero-contact-text span { font-size: 13px; }
}

@media (max-width: 480px) {
    .hero-title { font-size: 32px; }
    .hero-sub { font-size: 15px; }
    .hero-buttons { flex-direction: column; }
    .hero-stats { flex-direction: column; gap: 12px; }
    .hero-image img { height: 260px; }
    .section-title { font-size: 26px; }
    .contact-form { padding: 24px; }
}

/* ===================== BOOK VIEWER SECTION ===================== */
.book-viewer-section {
    background: linear-gradient(135deg, #0b1e3d 0%, #1a3565 50%, #0b1e3d 100%);
    padding: 80px 0 60px;
    text-align: center;
}
.book-viewer-section .section-tag { color: var(--primary); font-size: 14px; font-weight: 600; letter-spacing: 2px; text-transform: uppercase; margin-bottom: 12px; }
.book-viewer-section .section-title { font-family: 'Space Grotesk', sans-serif; font-size: 36px; font-weight: 800; color: var(--white); margin-bottom: 16px; }
.book-viewer-section .section-title span { color: var(--primary); }
.book-viewer-section .section-subtitle { color: rgba(255,255,255,0.6); font-size: 16px; margin-bottom: 40px; }

/* --- Realistic Book Container --- */
.book-container {
    max-width: 1060px;
    margin: 0 auto 40px;
    position: relative;
    user-select: none;
    perspective: 2000px;
}
.book-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
}
.the-book {
    width: 1006px;
    height: 520px;
    position: relative;
    transform-style: preserve-3d;
}
/* Left & right static pages */
.book-page-static {
    position: absolute;
    top: 0;
    width: 500px;
    height: 520px;
    background: #fff;
    overflow: hidden;
}
.book-page-static.left {
    left: 0;
    border-radius: 8px 0 0 8px;
    box-shadow: -6px 6px 25px rgba(0,0,0,0.25);
}
.book-page-static.right {
    right: 0;
    border-radius: 0 8px 8px 0;
    box-shadow: 6px 6px 25px rgba(0,0,0,0.25);
}
.book-page-static img {
    width: 100%; height: 100%;
    object-fit: contain;
    display: block;
    background: #fff;
}
/* Center spine */
.book-spine {
    position: absolute;
    left: 50%;
    top: 0;
    width: 6px;
    height: 100%;
    transform: translateX(-50%);
    background: linear-gradient(180deg, #c9b97a 0%, #8B7355 50%, #c9b97a 100%);
    box-shadow: 2px 0 8px rgba(0,0,0,0.3), -2px 0 8px rgba(0,0,0,0.3);
    z-index: 20;
    border-radius: 1px;
}
/* Inner shadow overlays for realism */
.book-page-static.left::after {
    content: '';
    position: absolute;
    top: 0; right: 0;
    width: 40px; height: 100%;
    background: linear-gradient(to left, rgba(0,0,0,0.08), transparent);
    pointer-events: none;
}
.book-page-static.right::before {
    content: '';
    position: absolute;
    top: 0; left: 0;
    width: 40px; height: 100%;
    background: linear-gradient(to right, rgba(0,0,0,0.08), transparent);
    pointer-events: none;
    z-index: 2;
}
/* === Flip page (the turning page) === */
.flip-page {
    position: absolute;
    top: 0;
    width: 500px;
    height: 520px;
    transform-style: preserve-3d;
    z-index: 15;
    pointer-events: none;
}
.flip-page-front, .flip-page-back {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    backface-visibility: hidden;
    overflow: hidden;
    background: #fff;
}
.flip-page-front { z-index: 2; }
.flip-page-back {
    transform: rotateY(180deg);
    z-index: 1;
}
.flip-page-front img, .flip-page-back img {
    width: 100%; height: 100%;
    object-fit: contain;
    display: block;
    background: #fff;
}
/* Shadow on flipping page */
.flip-page-front::after, .flip-page-back::after {
    content: '';
    position: absolute;
    top: 0;
    width: 60px; height: 100%;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.3s;
}
.flip-page-front::after {
    right: 0;
    background: linear-gradient(to left, rgba(0,0,0,0.15), transparent);
}
.flip-page-back::after {
    left: 0;
    background: linear-gradient(to right, rgba(0,0,0,0.15), transparent);
}
.flip-page.flipping .flip-page-front::after,
.flip-page.flipping .flip-page-back::after {
    opacity: 1;
}
/* Page curl shadow on the book surface */
.book-page-static .page-shadow {
    position: absolute;
    top: 0;
    width: 80px; height: 100%;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.3s;
    z-index: 3;
}
.book-page-static.left .page-shadow {
    right: 0;
    background: linear-gradient(to left, rgba(0,0,0,0.12), transparent);
}
.book-page-static.right .page-shadow {
    left: 0;
    background: linear-gradient(to right, rgba(0,0,0,0.12), transparent);
}
/* Page edge lines for book thickness */
.book-edge {
    position: absolute;
    top: 6px;
    width: 10px;
    height: calc(100% - 12px);
    z-index: 5;
    pointer-events: none;
}
.book-edge.left-edge {
    left: -10px;
    border-radius: 4px 0 0 4px;
    background: linear-gradient(to right, #e8e0cc, #f5f0e3);
    box-shadow: -2px 2px 6px rgba(0,0,0,0.15);
}
.book-edge.right-edge {
    right: -10px;
    border-radius: 0 4px 4px 0;
    background: linear-gradient(to left, #e8e0cc, #f5f0e3);
    box-shadow: 2px 2px 6px rgba(0,0,0,0.15);
}
/* Page corner fold hint */
.page-corner {
    position: absolute;
    bottom: 0; right: 0;
    width: 30px; height: 30px;
    cursor: pointer;
    pointer-events: all;
    z-index: 25;
}
.page-corner::before {
    content: '';
    position: absolute;
    bottom: 0; right: 0;
    width: 0; height: 0;
    border-style: solid;
    border-width: 0 0 24px 24px;
    border-color: transparent transparent rgba(0,0,0,0.06) transparent;
    transition: border-width 0.3s;
}
.page-corner:hover::before {
    border-width: 0 0 34px 34px;
}
/* Nav buttons */
.book-nav {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 28px;
    margin-top: 28px;
}
.book-nav-btn {
    background: rgba(255,255,255,0.08);
    border: 2px solid rgba(255,255,255,0.15);
    color: var(--white);
    width: 56px; height: 56px;
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    backdrop-filter: blur(4px);
}
.book-nav-btn:hover { background: var(--primary); border-color: var(--primary); color: var(--dark); transform: scale(1.1); }
.book-nav-btn:disabled { opacity: 0.25; cursor: not-allowed; transform: none; }
.book-nav-btn:disabled:hover { background: rgba(255,255,255,0.08); border-color: rgba(255,255,255,0.15); color: var(--white); transform: none; }
.book-page-info {
    color: rgba(255,255,255,0.65);
    font-size: 14px;
    font-weight: 500;
    min-width: 160px;
    letter-spacing: 0.5px;
}
/* Action buttons row */
.book-actions {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 16px;
    margin-top: 20px;
    flex-wrap: wrap;
}
.book-action-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 50px;
    font-size: 15px;
    font-weight: 600;
    font-family: 'Inter', sans-serif;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    border: 2px solid rgba(255,255,255,0.2);
    background: rgba(255,255,255,0.06);
    color: var(--white);
    backdrop-filter: blur(4px);
}
.book-action-btn:hover {
    background: rgba(255,255,255,0.15);
    border-color: rgba(255,255,255,0.4);
    transform: translateY(-2px);
}
.book-action-btn svg {
    width: 18px; height: 18px;
    fill: currentColor;
}
.book-action-btn.download-btn:hover { border-color: #4CAF50; color: #4CAF50; }
.book-action-btn.fullscreen-btn:hover { border-color: var(--primary); color: var(--primary); }

/* Fullscreen PDF Modal */
.pdf-fullscreen-modal {
    display: none;
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: rgba(0,0,0,0.92);
    backdrop-filter: blur(12px);
    z-index: 10001;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    padding: 20px;
    animation: fadeIn 0.3s ease;
}
.pdf-fullscreen-modal.active { display: flex; }
.pdf-fullscreen-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    max-width: 1200px;
    margin-bottom: 16px;
    padding: 0 10px;
}
.pdf-fullscreen-title {
    color: var(--white);
    font-family: 'Space Grotesk', sans-serif;
    font-size: 20px;
    font-weight: 700;
}
.pdf-fullscreen-close {
    width: 44px; height: 44px;
    border-radius: 50%;
    background: rgba(255,255,255,0.1);
    border: 2px solid rgba(255,255,255,0.2);
    color: var(--white);
    font-size: 22px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}
.pdf-fullscreen-close:hover { background: #e74c3c; border-color: #e74c3c; }
.pdf-fullscreen-body {
    width: 100%;
    max-width: 1200px;
    flex: 1;
    min-height: 0;
    display: flex;
    justify-content: center;
    align-items: center;
}
.pdf-fullscreen-body img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 8px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.5);
    background: #fff;
}
.pdf-fullscreen-nav {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
    margin-top: 16px;
    padding-bottom: 10px;
}
.pdf-fs-nav-btn {
    background: rgba(255,255,255,0.1);
    border: 2px solid rgba(255,255,255,0.2);
    color: var(--white);
    width: 48px; height: 48px;
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-size: 18px;
    cursor: pointer;
    transition: all 0.3s ease;
}
.pdf-fs-nav-btn:hover { background: var(--primary); border-color: var(--primary); color: var(--dark); }
.pdf-fs-nav-btn:disabled { opacity: 0.25; cursor: not-allowed; }
.pdf-fs-nav-btn:disabled:hover { background: rgba(255,255,255,0.1); border-color: rgba(255,255,255,0.2); color: var(--white); }
.pdf-fs-page-info {
    color: rgba(255,255,255,0.7);
    font-size: 14px;
    font-weight: 500;
    min-width: 120px;
}
.pdf-fs-download {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 22px;
    background: rgba(76,175,80,0.15);
    border: 2px solid rgba(76,175,80,0.4);
    color: #4CAF50;
    border-radius: 50px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.3s ease;
    font-family: 'Inter', sans-serif;
}
.pdf-fs-download:hover { background: #4CAF50; color: #fff; border-color: #4CAF50; }
.pdf-fs-download svg { width: 16px; height: 16px; fill: currentColor; }

.book-enroll-btn {
    display: inline-block;
    margin-top: 36px;
    padding: 18px 48px;
    background: linear-gradient(135deg, var(--primary) 0%, #f4b942 100%);
    color: var(--dark);
    font-size: 18px;
    font-weight: 700;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 8px 30px rgba(232,165,39,0.4);
    animation: pulseGlow 2s ease-in-out infinite;
    font-family: 'Inter', sans-serif;
}
.book-enroll-btn:hover { transform: translateY(-3px); box-shadow: 0 12px 40px rgba(232,165,39,0.6); }
@keyframes pulseGlow {
    0%, 100% { box-shadow: 0 8px 30px rgba(232,165,39,0.4); }
    50% { box-shadow: 0 8px 40px rgba(232,165,39,0.7); }
}

/* Camp Video Section */
.camp-video-block {
    margin-top: 60px;
    text-align: center;
}
.camp-video-block .video-label {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: var(--primary);
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 14px;
}
.camp-video-block .video-label svg {
    width: 20px; height: 20px; fill: var(--primary);
}
.camp-video-block .video-heading {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 28px;
    font-weight: 700;
    color: var(--white);
    margin-bottom: 28px;
}
.camp-video-block .video-heading span { color: var(--primary); }
.camp-video-wrapper {
    position: relative;
    max-width: 820px;
    margin: 0 auto;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0,0,0,0.45), 0 0 0 1px rgba(255,255,255,0.06);
    background: #000;
    aspect-ratio: 16 / 9;
    cursor: pointer;
}
.camp-video-wrapper iframe {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    border: none;
}
.camp-video-wrapper::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 16px;
    border: 1px solid rgba(255,255,255,0.08);
    pointer-events: none;
    z-index: 2;
}
/* Thumbnail overlay */
.video-thumb {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 3;
    cursor: pointer;
    transition: opacity 0.4s ease;
}
.video-thumb img {
    width: 100%; height: 100%;
    object-fit: cover;
    display: block;
}
.video-thumb::after {
    content: '';
    position: absolute;
    inset: 0;
    background: rgba(0,0,0,0.3);
    transition: background 0.3s ease;
}
.video-thumb:hover::after {
    background: rgba(0,0,0,0.15);
}
.video-play-btn {
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    z-index: 4;
    width: 80px; height: 80px;
    background: rgba(232,165,39,0.95);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 8px 30px rgba(232,165,39,0.5), 0 0 0 8px rgba(232,165,39,0.15);
    transition: all 0.3s ease;
}
.video-thumb:hover .video-play-btn {
    transform: translate(-50%, -50%) scale(1.1);
    box-shadow: 0 10px 40px rgba(232,165,39,0.6), 0 0 0 12px rgba(232,165,39,0.2);
}
.video-play-btn svg {
    width: 32px; height: 32px;
    fill: var(--dark);
    margin-left: 4px;
}
.video-thumb.hidden {
    opacity: 0;
    pointer-events: none;
}
@media (max-width: 650px) {
    .camp-video-block { margin-top: 40px; }
    .camp-video-block .video-heading { font-size: 22px; margin-bottom: 20px; }
    .camp-video-wrapper { border-radius: 12px; }
    .video-play-btn { width: 60px; height: 60px; }
    .video-play-btn svg { width: 24px; height: 24px; }
}

/* Enrollment Form Modal */
.enroll-modal {
    display: none;
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: rgba(0,0,0,0.8);
    backdrop-filter: blur(10px);
    z-index: 10000;
    justify-content: center;
    align-items: center;
    animation: fadeIn 0.3s ease;
    overflow-y: auto;
    padding: 20px;
}
.enroll-modal.active { display: flex; }
.enroll-modal-inner {
    position: relative;
    max-width: 520px;
    width: 100%;
    animation: slideUp 0.4s ease;
}
.enroll-modal-close {
    position: absolute;
    top: -16px; right: -16px;
    width: 40px; height: 40px;
    background: var(--primary);
    color: var(--dark);
    border: none;
    border-radius: 50%;
    font-size: 20px;
    font-weight: 700;
    cursor: pointer;
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 15px rgba(0,0,0,0.3);
    transition: all 0.3s ease;
}
.enroll-modal-close:hover { transform: scale(1.1); }

/* Book viewer responsive */
@media (max-width: 1100px) {
    .the-book { width: 806px; height: 420px; }
    .book-page-static { width: 400px; height: 420px; }
    .flip-page { width: 400px; height: 420px; }
}
@media (max-width: 860px) {
    .the-book { width: 606px; height: 320px; }
    .book-page-static { width: 300px; height: 320px; }
    .flip-page { width: 300px; height: 320px; }
    .book-edge { display: none; }
}
@media (max-width: 650px) {
    .the-book { width: 92vw; height: 60vw; }
    .book-page-static.left { display: none; }
    .book-spine { display: none; }
    .book-page-static.right { left: 0; right: 0; width: 100%; border-radius: 8px; }
    .book-page-static.right::before { display: none; }
    .flip-page { width: 100%; height: 100%; }
    .book-edge { display: none; }
    .book-viewer-section { padding: 50px 0 40px; }
    .book-enroll-btn { padding: 16px 36px; font-size: 16px; }
    .enroll-modal-close { top: -12px; right: -4px; }
    .book-nav-btn { width: 44px; height: 44px; font-size: 16px; }
    .book-actions { gap: 10px; }
    .book-action-btn { padding: 10px 20px; font-size: 13px; }
    .pdf-fullscreen-title { font-size: 16px; }
}
    </style>

</head>
<body>

<!-- ===================== NAVBAR ===================== -->
<nav class="navbar" id="navbar">
    <div class="nav-container">
        <a href="#" class="nav-logo">
            <img src="assets/images/logo.png" alt="Classs Robotics Logo" class="logo-icon">
            <span class="logo-text">CLASSS <span>ROBOTICS</span></span>
        </a>
        <ul class="nav-links" id="navLinks">
            <li><a href="#home">Home</a></li>
            <li><a href="#about">About</a></li>
            <li><a href="#programs">Programs</a></li>
            <li><a href="#curriculum">Curriculum</a></li>
            <li><a href="#contact">Contact</a></li>
        </ul>
        <a href="#book-viewer" class="nav-cta">Enroll Now</a>
        <button class="nav-toggle" id="navToggle" aria-label="Toggle menu">
            <span></span><span></span><span></span>
        </button>
    </div>
</nav>

<!-- ===================== HERO ===================== -->
<section class="hero" id="home">
     <!-- Contact Card -->
        <div class="hero-contact-card" style="display: none;">
            <h3>📞 Quick Contact</h3>
            <a href="tel:+919480551221" class="hero-contact-item">
                <div class="hero-contact-icon">📞</div>
                <div class="hero-contact-text">
                    <strong>Phone</strong>
                    <span>9480551221, 9187389981</span>
                </div>
            </a>
            <a href="mailto:classsrobotics12@gmail.com" class="hero-contact-item">
                <div class="hero-contact-icon">📧</div>
                <div class="hero-contact-text">
                    <strong>Email</strong>
                    <span>classsrobotics12@gmail.com</span>
                </div>
            </a>
        </div>
    <div class="hero-overlay"></div>

    <div class="hero-content">
       

        <div class="hero-text">
            <p class="hero-badge">🚀 Summer 2026 — Registrations Open</p>
            <h1 class="hero-title">
                Robotics &amp; AI<br>
                <span class="highlight">Summer Camp</span>
            </h1>
            <p class="hero-sub">Empowering young minds through hands-on robotics, coding &amp; artificial intelligence. Build real robots, learn real skills.</p>
            <div class="hero-buttons">
                <a href="#programs" class="btn btn-primary">Explore Programs</a>
                <a href="#about" class="btn btn-outline">Learn More</a>
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            <div class="hero-stats">
                <div class="hero-stat"><strong>500+</strong><span>Students Trained</span></div>
                <div class="hero-stat"><strong>15+</strong><span>Robot Projects</span></div>
                <div class="hero-stat"><strong>2</strong><span>Skill Levels</span></div>
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        <div class="hero-image">
            <img src="assets/images/img1.jpeg" alt="Robotics Summer Camp">
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<!-- ===================== ABOUT ===================== -->
<section class="section about" id="about">
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                <img src="assets/images/img8.jpeg" alt="Students building robots" class="about-img about-img-1">
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                <p class="section-tag">About Our Camp</p>
                <h2 class="section-title">Where Young Minds Meet <span>Future Technology</span></h2>
                <p class="about-desc">Classs Robotics Summer Camp is a premier hands-on STEM education program designed for students aged 8–16. Our camp bridges the gap between classroom learning and real-world innovation through exciting robotics and AI projects.</p>
                <div class="about-features">
                    <div class="about-feature">
                        <div class="af-icon">🤖</div>
                        <div><strong>Hands-On Building</strong><p>Students build and program real robots from scratch</p></div>
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                    <div class="about-feature">
                        <div class="af-icon">🧠</div>
                        <div><strong>AI &amp; Sensors</strong><p>Explore artificial intelligence, sensors &amp; automation</p></div>
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                        <div class="af-icon">💻</div>
                        <div><strong>Coding Skills</strong><p>Learn block coding, Arduino programming &amp; Python</p></div>
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                        <div class="af-icon">🏆</div>
                        <div><strong>Competitions</strong><p>Showcase skills in robot challenges &amp; earn certificates</p></div>
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</section>

<!-- ===================== BOOK VIEWER ===================== -->
<section class="book-viewer-section" id="book-viewer">
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        <p class="section-tag">Explore Our Camp</p>
        <h2 class="section-title">Robotics Summer Camp <span>Presentation</span></h2>
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                <a class="book-action-btn download-btn" href="docs/ROBOTICS SUMMER CAMP ppt (1).pdf" download title="Download PDF">
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        <button class="book-enroll-btn" onclick="openEnrollModal()">🎓 Enroll Now</button>

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                Watch Our Camp
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            <h3 class="video-heading">See What <span>Students Build</span></h3>
            <div class="camp-video-wrapper">
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            Download
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<!-- ===================== PROGRAMS ===================== -->
<section class="section programs" id="programs">
    <div class="container">
        <p class="section-tag center">Our Programs</p>
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        <p class="section-subtitle">Structured curriculum designed for beginners and advanced learners</p>

        <!-- PDF Downloads -->
        <div class="pdf-downloads">
            <a href="docs/Level 1- curriculum (1).pdf" target="_blank" class="pdf-download-link" download>
                <span class="pdf-icon">📄</span>
                <span>Level 1 Curriculum PDF</span>
            </a>
            <a href="docs/Level 2- Curriculum(1).pdf" target="_blank" class="pdf-download-link" download>
                <span class="pdf-icon">📄</span>
                <span>Level 2 Curriculum PDF</span>
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            <a href="docs/ROBOTICS SUMMER CAMP ppt (1).pdf" target="_blank" class="pdf-download-link" download>
                <span class="pdf-icon">📄</span>
                <span>Summer Camp Presentation</span>
            </a>
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            <div class="program-card">
                <div class="program-badge">Beginner</div>
                <img src="assets/images/img5.jpeg" alt="Level 1 Robotics" class="program-img">
                <div class="program-body">
                    <h3>Level 1 — Foundation</h3>
                    <p class="program-age">Ages 8–12 · 2 Weeks</p>
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                        <li>Introduction to Robotics &amp; STEM Basics</li>
                        <li>Robot Mechanics — Gears, Motors &amp; Wheels</li>
                        <li>Block-Based Coding (Scratch / mBlock)</li>
                        <li>Sensor Basics — Light, Sound &amp; Touch</li>
                        <li>Build Your First Line-Following Robot</li>
                        <li>Mini Project &amp; Showcase Day</li>
                    </ul>
                    <a href="#book-viewer" class="btn btn-primary btn-full">Enroll in Level 1</a>
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            <div class="program-card featured">
                <div class="program-badge">Advanced</div>
                <img src="assets/images/img6.jpeg" alt="Level 2 Robotics" class="program-img">
                <div class="program-body">
                    <h3>Level 2 — Advanced Builder</h3>
                    <p class="program-age">Ages 12–16 · 3 Weeks</p>
                    <ul class="program-list">
                        <li>Advanced Robot Design &amp; 3D Modeling</li>
                        <li>Arduino Programming &amp; Circuit Design</li>
                        <li>AI Fundamentals — Machine Learning Basics</li>
                        <li>Bluetooth / WiFi Controlled Robots</li>
                        <li>Obstacle Avoidance &amp; Autonomous Navigation</li>
                        <li>Final Competition &amp; Certification</li>
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                    <a href="#book-viewer" class="btn btn-primary btn-full">Enroll in Level 2</a>
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            </div>
        </div>
    </div>
</section>

<!-- ===================== CURRICULUM ===================== -->
<section class="section curriculum-section" id="curriculum">
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            <div class="curr-card">
                <div class="curr-num">01</div>
                <h4>Robotics Fundamentals</h4>
                <p>Understanding robot anatomy — chassis, wheels, motors, power supply. Hands-on assembly of basic robot platforms.</p>
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            <div class="curr-card">
                <div class="curr-num">02</div>
                <h4>Electronics &amp; Circuits</h4>
                <p>Introduction to breadboards, LEDs, resistors, and basic circuit design. Students build working circuits.</p>
            </div>
            <div class="curr-card">
                <div class="curr-num">03</div>
                <h4>Programming &amp; Logic</h4>
                <p>Block coding for beginners, Arduino C for advanced. Conditional logic, loops, and sensor-driven programs.</p>
            </div>
            <div class="curr-card">
                <div class="curr-num">04</div>
                <h4>Sensors &amp; Automation</h4>
                <p>Working with ultrasonic, IR, light &amp; temperature sensors. Building robots that react to their environment.</p>
            </div>
            <div class="curr-card">
                <div class="curr-num">05</div>
                <h4>AI &amp; Smart Robotics</h4>
                <p>Introduction to artificial intelligence concepts. Voice control, object detection &amp; decision-making algorithms.</p>
            </div>
            <div class="curr-card">
                <div class="curr-num">06</div>
                <h4>Project &amp; Competition</h4>
                <p>Students design, build &amp; program a complete robot for the final showcase competition. Certificates awarded.</p>
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        </div>
    </div>
</section>

<!-- ===================== WHY CHOOSE US ===================== -->
<section class="section why-us">
    <div class="container">
        <p class="section-tag center">Why Classs Robotics?</p>
        <h2 class="section-title center">The <span>Smart Choice</span> for Your Child</h2>
        <div class="why-grid">
            <div class="why-card"><div class="why-icon">👨‍🏫</div><h4>Expert Mentors</h4><p>Industry-trained instructors with passion for teaching young innovators</p></div>
            <div class="why-card"><div class="why-icon">🔬</div><h4>Real Equipment</h4><p>Professional-grade robotics kits, sensors, Arduino boards &amp; 3D printers</p></div>
            <div class="why-card"><div class="why-icon">👥</div><h4>Small Batches</h4><p>Limited students per batch for personalized attention</p></div>
            <div class="why-card"><div class="why-icon">📜</div><h4>Certification</h4><p>Recognized completion certificates to boost your child's portfolio</p></div>
            <div class="why-card"><div class="why-icon">🎯</div><h4>Project-Based</h4><p>Learn by doing — every session ends with a working robot or project</p></div>
            <div class="why-card"><div class="why-icon">🛡️</div><h4>Safe Environment</h4><p>Supervised, child-friendly labs with safety protocols in place</p></div>
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    </div>
</section>

<!-- ===================== CTA / CONTACT ===================== -->
<section class="section contact" id="contact">
    <div class="container">
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            <div class="contact-info">
                <p class="section-tag">Get In Touch</p>
                <h2 class="section-title">Ready to Build the <span>Future?</span></h2>
                <p class="contact-desc">Enroll your child in the most exciting summer camp experience. Limited seats available — register today!</p>
                <div class="contact-details">
                    <div class="cd-item"><span class="cd-icon">📍</span><div><strong>Location</strong><p>Bengaluru, Karnataka</p></div></div>
                    <div class="cd-item"><span class="cd-icon">📞</span><div><strong>Phone</strong><p>9480551221, 9187389981</p></div></div>
                    <div class="cd-item"><span class="cd-icon">📧</span><div><strong>Email</strong><p>classsrobotics12@gmail.com</p></div></div>
                    <div class="cd-item"><span class="cd-icon">🕐</span><div><strong>Camp Dates</strong><p>April 1 — May 30</p></div></div>
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                <h3><span class="logo-icon">⚙️</span> CLASSS <span>ROBOTICS</span></h3>
                <p>Empowering the next generation of innovators through robotics, coding &amp; AI education.</p>
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        'docs/slides/9.jpg','docs/slides/10.jpg','docs/slides/11.jpg','docs/slides/12.jpg'
    ];
    var total = pages.length;
    var current = 0;
    var animating = false;
    var DURATION = 800;

    var leftImg = document.getElementById('leftImg');
    var rightImg = document.getElementById('rightImg');
    var flipPageEl = document.getElementById('flipPage');
    var flipFront = document.getElementById('flipFront').querySelector('img');
    var flipBack = document.getElementById('flipBack').querySelector('img');
    var leftShadow = document.getElementById('leftShadow');
    var rightShadow = document.getElementById('rightShadow');
    var btnPrev = document.getElementById('btnPrev');
    var btnNext = document.getElementById('btnNext');
    var pageInfo = document.getElementById('pageInfo');
    var corner = document.getElementById('pageCorner');

    pages.forEach(function(s){ var i = new Image(); i.src = s; });

    function isMobile() { return window.innerWidth <= 650; }

    function updateView() {
        if (isMobile()) {
            // Single page mode on mobile
            rightImg.src = pages[current];
            rightImg.alt = 'Page ' + (current + 1);
            rightImg.style.visibility = 'visible';
            pageInfo.textContent = 'Page ' + (current + 1) + ' of ' + total;
            btnPrev.disabled = (current <= 0);
            btnNext.disabled = (current >= total - 1);
            corner.style.display = (current < total - 1) ? 'block' : 'none';
        } else {
            // Two-page spread on desktop
            leftImg.src = pages[current];
            leftImg.alt = 'Page ' + (current + 1);
            if (current + 1 < total) {
                rightImg.src = pages[current + 1];
                rightImg.alt = 'Page ' + (current + 2);
                rightImg.style.visibility = 'visible';
                corner.style.display = 'block';
            } else {
                rightImg.style.visibility = 'hidden';
                corner.style.display = 'none';
            }
            var end = Math.min(current + 2, total);
            pageInfo.textContent = 'Pages ' + (current + 1) + '\u2013' + end + ' of ' + total;
            btnPrev.disabled = (current <= 0);
            btnNext.disabled = (current + 2 >= total);
        }
    }

    function animateFlip(direction) {
        // direction: 1 = next, -1 = prev
        var step = isMobile() ? 1 : 2;
        if (direction === 1) {
            if (isMobile()) {
                if (animating || current >= total - 1) return;
            } else {
                if (animating || current + 2 >= total) return;
            }
        } else {
            if (animating || current <= 0) return;
        }
        animating = true;

        if (isMobile()) {
            // Simple crossfade for mobile single page
            var targetIdx = current + direction;
            rightImg.style.transition = 'opacity 0.4s';
            rightImg.style.opacity = '0';
            setTimeout(function() {
                current = targetIdx;
                updateView();
                rightImg.style.opacity = '1';
                setTimeout(function() {
                    rightImg.style.transition = '';
                    animating = false;
                }, 400);
            }, 400);
            return;
        }

        // Desktop 3D flip
        if (direction === 1) {
            var nextLeft = current + step;
            var nextRight = current + step + 1;
            flipFront.src = pages[current + 1];
            flipBack.src = pages[nextLeft];
            flipPageEl.style.left = '50%';
            flipPageEl.style.right = 'auto';
            flipPageEl.style.transformOrigin = 'left center';
            flipPageEl.style.transform = 'rotateY(0deg)';
            flipPageEl.style.display = 'block';
            flipPageEl.classList.add('flipping');
            rightShadow.style.opacity = '0';
            if (nextRight < total) { rightImg.src = pages[nextRight]; }
            else { rightImg.style.visibility = 'hidden'; }
        } else {
            var prevLeft = current - step;
            var prevRight = current - 1;
            flipBack.src = pages[current];
            flipFront.src = pages[prevRight];
            flipPageEl.style.left = 'auto';
            flipPageEl.style.right = '50%';
            flipPageEl.style.transformOrigin = 'right center';
            flipPageEl.style.transform = 'rotateY(0deg)';
            flipPageEl.style.display = 'block';
            flipPageEl.classList.add('flipping');
            leftShadow.style.opacity = '0';
            leftImg.src = pages[prevLeft];
        }

        var startTime = performance.now();
        function tick(now) {
            var elapsed = now - startTime;
            var progress = Math.min(elapsed / DURATION, 1);
            var ease = progress < 0.5
                ? 2 * progress * progress
                : 1 - Math.pow(-2 * progress + 2, 2) / 2;
            var angle = direction === 1 ? ease * -180 : ease * 180;
            flipPageEl.style.transform = 'rotateY(' + angle + 'deg)';
            var shadow = Math.sin(progress * Math.PI) * 0.7;
            if (direction === 1) {
                leftShadow.style.opacity = shadow;
                rightShadow.style.opacity = shadow * 0.5;
            } else {
                rightShadow.style.opacity = shadow;
                leftShadow.style.opacity = shadow * 0.5;
            }
            if (progress < 1) {
                requestAnimationFrame(tick);
            } else {
                flipPageEl.style.display = 'none';
                flipPageEl.classList.remove('flipping');
                leftShadow.style.opacity = '0';
                rightShadow.style.opacity = '0';
                current = direction === 1 ? current + step : current - step;
                updateView();
                animating = false;
            }
        }
        requestAnimationFrame(tick);
    }

    window.flipNext = function() { animateFlip(1); };
    window.flipPrev = function() { animateFlip(-1); };

    updateView();
    window.addEventListener('resize', function() { updateView(); });

    document.addEventListener('keydown', function(e) {
        if (document.getElementById('pdfFullscreenModal').classList.contains('active')) return;
        if (e.key === 'ArrowRight') flipNext();
        if (e.key === 'ArrowLeft') flipPrev();
    });

    // Swipe support for mobile
    var touchStartX = 0;
    var bookEl = document.getElementById('theBook');
    bookEl.addEventListener('touchstart', function(e) {
        touchStartX = e.changedTouches[0].screenX;
    }, {passive: true});
    bookEl.addEventListener('touchend', function(e) {
        var diff = e.changedTouches[0].screenX - touchStartX;
        if (Math.abs(diff) > 50) {
            if (diff < 0) flipNext();
            else flipPrev();
        }
    }, {passive: true});
})();

// ===================== FULLSCREEN PDF VIEWER =====================
(function() {
    var slides = [
        'docs/slides/1.jpg','docs/slides/2.jpg','docs/slides/3.jpg','docs/slides/4.jpg',
        'docs/slides/5.jpg','docs/slides/6.jpg','docs/slides/7.jpg','docs/slides/8.jpg',
        'docs/slides/9.jpg','docs/slides/10.jpg','docs/slides/11.jpg','docs/slides/12.jpg'
    ];
    var fsTotal = slides.length;
    var fsCurrent = 0;

    var modal = document.getElementById('pdfFullscreenModal');
    var fsImg = document.getElementById('pdfFsImage');
    var fsInfo = document.getElementById('pdfFsInfo');
    var fsPrev = document.getElementById('pdfFsPrev');
    var fsNext = document.getElementById('pdfFsNext');

    function fsUpdate() {
        fsImg.src = slides[fsCurrent];
        fsInfo.textContent = 'Page ' + (fsCurrent + 1) + ' of ' + fsTotal;
        fsPrev.disabled = (fsCurrent <= 0);
        fsNext.disabled = (fsCurrent >= fsTotal - 1);
    }

    window.openFullscreenPDF = function() {
        fsCurrent = 0;
        fsUpdate();
        modal.classList.add('active');
        document.body.style.overflow = 'hidden';
    };

    window.closeFullscreenPDF = function() {
        modal.classList.remove('active');
        document.body.style.overflow = '';
    };

    window.pdfFsNav = function(dir) {
        var next = fsCurrent + dir;
        if (next < 0 || next >= fsTotal) return;
        fsCurrent = next;
        fsUpdate();
    };

    // Close on backdrop click
    modal.addEventListener('click', function(e) {
        if (e.target === modal) closeFullscreenPDF();
    });

    // Keyboard nav in fullscreen
    document.addEventListener('keydown', function(e) {
        if (!modal.classList.contains('active')) return;
        if (e.key === 'Escape') closeFullscreenPDF();
        if (e.key === 'ArrowRight') pdfFsNav(1);
        if (e.key === 'ArrowLeft') pdfFsNav(-1);
    });

    // Swipe in fullscreen
    var fsTouchX = 0;
    modal.addEventListener('touchstart', function(e) {
        fsTouchX = e.changedTouches[0].screenX;
    }, {passive: true});
    modal.addEventListener('touchend', function(e) {
        var diff = e.changedTouches[0].screenX - fsTouchX;
        if (Math.abs(diff) > 50) {
            if (diff < 0) pdfFsNav(1);
            else pdfFsNav(-1);
        }
    }, {passive: true});
})();


</script>
</body>
</html>