/* Theme Variables */
:root {
    /* Colors */
    --bg-color: #ffffff;
    --text-color: #1a202c;
    --text-secondary: #4a5568;
    --accent-color: #48bb78;
    --accent-hover: #38a169;
    --card-bg: #f7fafc;
    --card-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --border-color: #e2e8f0;
    --module-bg: #ffffff;
    --module-border: #e2e8f0;
    --module-hover: #f8fafc;
    --header-bg: linear-gradient(135deg, #1a202c, #2d3748);
    --footer-bg: #1a202c;
    --footer-text: #f8f9fa;
    --code-bg: #f1f5f9;
    --code-color: #1e293b;
    --hero-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --tab-bg: #f1f5f9;
    --tab-active-bg: #4f46e5;
    --tab-text: #4a5568;
    --tab-active-text: #ffffff;
    --video-btn-bg: #9f7aea;
    --video-btn-hover: #805ad5;
    --code-btn-bg: #4299e1;
    --code-btn-hover: #3182ce;
    --study-btn-bg: #48bb78;
    --study-btn-hover: #38a169;
    --primary-color: #1a202c;
    --secondary-color: #2d3748;
    --light-text: #f8f9fa;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --border-radius: 12px;
    --transition: all 0.3s ease;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    --font-main: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    --font-code: 'Fira Code', 'Courier New', monospace;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    padding: 0;
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Skip link styles */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--primary-color);
    color: var(--light-text);
    padding: 8px 16px;
    z-index: 100;
    transition: var(--transition);
}

.skip-link:focus {
    top: 0;
}

/* Focus styles for better keyboard navigation */
a:focus, button:focus, input:focus, select:focus, textarea:focus {
    outline: 3px solid var(--accent-color);
    outline-offset: 2px;
}

/* Ensure focus is visible for keyboard users */
[tabindex="-1"]:focus {
    outline: none !important;
}

/* Header Styles */
header {
    background: var(--header-bg);
    color: white;
    padding: 16px 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

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

header h1 {
    font-size: 1.8rem;
    font-weight: 700;
    margin: 0;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 30px;
}

nav a {
    color: var(--light-text);
    text-decoration: none;
    font-weight: 600;
    font-size: 1rem;
    transition: var(--transition);
}

nav a:hover {
    color: var(--accent-color);
}

.social-links {
    display: flex;
    gap: 10px;
    align-items: center;
}

.social-icon, .flag {
    width: 28px;
    height: 20px;
    object-fit: cover;
    border-radius: 3px;
    transition: transform 0.3s ease;
}

.social-icon:hover, .flag:hover {
    transform: scale(1.2);
}

.header-spacer {
    height: 80px;
}

/* Hero Section */
#hero {
    background: url('../images/hero-bg.jpg') no-repeat center/cover;
    position: relative;
    color: white;
    text-align: center;
    padding: 140px 20px;
}

#hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    z-index: 1;
}

#hero .container {
    position: relative;
    z-index: 2;
}

#hero h2 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 24px;
    animation: slideInUp 1s ease-out;
}

#hero p {
    font-size: 1.25rem;
    margin-bottom: 24px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.free-lesson-message {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--accent-color);
    margin-bottom: 24px;
}

.btn {
    background: #4299e1;
    color: white;
    padding: 14px 32px;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    display: inline-block;
    margin: 12px;
}

.btn:hover {
    background: #3182ce;
    transform: translateY(-3px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.free-lesson-btn {
    background: var(--study-btn-bg);
    color: var(--primary-color);
}

.free-lesson-btn:hover {
    background: var(--study-btn-hover);
}

.secondary-btn {
    background: transparent;
    border: 2px solid white;
}

.secondary-btn:hover {
    background: white;
    color: var(--primary-color);
}

.youtube-btn {
    background: #ff0000;
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 32px;
}

.youtube-btn:hover {
    background: #cc0000;
    transform: translateY(-3px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.youtube-btn img {
    width: 28px;
    height: 20px;
    object-fit: cover;
}

/* Course Section */
#course {
    padding: 120px 20px;
    background: var(--bg-color);
}

#course h2 {
    font-size: 3rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 40px;
    color: var(--text-color);
}

#course > p {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 40px;
    font-size: 1.15rem;
    color: var(--text-secondary);
}

.module {
    background: var(--module-bg);
    border: 1px solid var(--module-border);
    border-radius: var(--border-radius);
    padding: 24px;
    margin-bottom: 24px;
    box-shadow: var(--card-shadow);
    transition: var(--transition);
}

.module:hover {
    background: var(--module-hover);
    transform: translateY(-5px);
}

.module h3 {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 16px;
}

.module p {
    font-size: 1.15rem;
    margin-bottom: 16px;
    color: var(--text-secondary);
}

.module ul {
    list-style: disc;
    padding-left: 24px;
    margin-bottom: 16px;
    font-size: 1.1rem;
    color: var(--text-secondary);
}

.module-buttons {
    display: flex;
    gap: 10px;
    margin-top: 16px;
    flex-wrap: wrap;
}

.module-buttons a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 20px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: 6px;
    transition: var(--transition);
    flex: 1;
    min-width: 120px;
    text-align: center;
    border: none;
    cursor: pointer;
}

.module .video-btn {
    background: var(--video-btn-bg);
    color: white;
}

.module .video-btn:hover {
    background: var(--video-btn-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.module .code-btn {
    background: var(--code-btn-bg);
    color: white;
}

.module .code-btn:hover {
    background: var(--code-btn-hover);
    transform: translateY(-2px);
}

.module .study-btn {
    background: var(--study-btn-bg);
    color: white;
}

.module .study-btn:hover {
    background: var(--study-btn-hover);
    transform: translateY(-2px);
}

/* Anniversary Banner */
#anniversary-banner {
    background: var(--card-bg);
    color: var(--text-color);
    text-align: center;
    padding: 40px 20px;
    margin: 20px 0;
    position: relative;
    overflow: hidden;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

#anniversary-banner h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 20px;
}

#anniversary-banner p {
    font-size: 1.2rem;
    margin-bottom: 20px;
    color: var(--text-secondary);
}

#anniversary-banner .neon-text {
    font-size: 4rem;
    font-weight: 700;
    color: #00ffcc;
    text-shadow: 0 0 10px #00ffcc, 0 0 20px #00ffcc, 0 0 30px #00ffcc;
    animation: neonGlow 1.5s ease-in-out infinite alternate;
}

@keyframes neonGlow {
    from {
        text-shadow: 0 0 5px #00ffcc, 0 0 10px #00ffcc, 0 0 15px #00ffcc;
    }
    to {
        text-shadow: 0 0 10px #00ffcc, 0 0 20px #00ffcc, 0 0 30px #00ffcc;
    }
}

/* About Section */
#about {
    padding: 120px 20px;
    background: var(--bg-color);
}

#about h2 {
    font-size: 3rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 40px;
    color: var(--text-color);
}

.about-content {
    display: flex;
    gap: 48px;
    align-items: center;
}

.about-img {
    width: 350px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.about-img:hover {
    transform: scale(1.05);
}

.about-text p {
    margin-bottom: 20px;
    font-size: 1.15rem;
    color: var(--text-secondary);
}

.about-text strong {
    color: #4299e1;
}

.about-text ul {
    list-style: disc;
    padding-left: 24px;
    font-size: 1.15rem;
}

/* Games Section */
#games {
    padding: 120px 20px;
    background: var(--bg-color);
}

#games h2 {
    font-size: 3rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 40px;
    color: var(--text-color);
}

#games > p {
    text-align: center;
    font-size: 1.25rem;
    margin-bottom: 48px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    color: var(--text-secondary);
}

.games-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--spacing-md);
}

.game-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    text-align: center;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    opacity: 0;
    animation: fadeInUp 0.6s ease forwards;
}

.game-card:nth-child(1) { animation-delay: 0.1s; }
.game-card:nth-child(2) { animation-delay: 0.2s; }
.game-card:nth-child(3) { animation-delay: 0.3s; }
.game-card:nth-child(4) { animation-delay: 0.4s; }
.game-card:nth-child(5) { animation-delay: 0.5s; }
.game-card:nth-child(6) { animation-delay: 0.6s; }
.game-card:nth-child(7) { animation-delay: 0.7s; }
.game-card:nth-child(8) { animation-delay: 0.8s; }

.game-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.15);
}

.game-img {
    width: 100%;
    aspect-ratio: 16 / 9;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 16px;
    transition: transform 0.4s ease;
}

.game-img:hover {
    transform: scale(1.08);
}

.game-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 12px;
}

.game-info {
    padding: var(--spacing-md);
}

.game-info span {
    display: block;
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.game-info strong {
    color: var(--text-color);
}

.game-btn {
    background: #4299e1;
    color: white;
    padding: 12px 24px;
    font-size: 1rem;
    transition: var(--transition);
}

.game-btn:hover {
    background: #3182ce;
    transform: translateY(-2px);
}

/* YouTube Videos Section */
#youtube-videos {
    padding: 60px 0;
    background-color: var(--bg-color);
}

.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 30px;
}

.video-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}

.video-thumbnail {
    position: relative;
    display: block;
    overflow: hidden;
}

.video-thumbnail img {
    width: 100%;
    height: auto;
    aspect-ratio: 16 / 9;
    object-fit: cover;
}

.play-button {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    background: rgba(255, 0, 0, 0.7);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.3s ease;
}

.play-button:hover {
    background: rgba(255, 0, 0, 0.9);
}

.video-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-color);
    margin: 16px 16px 8px;
    text-align: left;
}

.video-description {
    font-size: 1rem;
    color: var(--text-secondary);
    margin: 0 16px 16px;
    text-align: left;
}

/* Contact Section */
#contact {
    padding: 120px 20px;
    background: var(--header-bg);
    color: white;
    text-align: center;
}

#contact h2 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 40px;
}

#contact p {
    font-size: 1.25rem;
    margin-bottom: 32px;
}

.contact-info {
    list-style: none;
    margin: 0 auto 40px;
    padding: 0;
    text-align: center;
    max-width: 600px;
}

.contact-info li {
    font-size: 1.2rem;
    margin-bottom: 16px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.contact-info a {
    color: var(--accent-color);
    text-decoration: none;
    transition: var(--transition);
}

.contact-info a:hover {
    color: var(--accent-hover);
}

/* Footer */
footer {
    background: var(--footer-bg);
    color: var(--footer-text);
    text-align: center;
    padding: 32px 0;
}

footer p {
    font-size: 1rem;
    margin: 0;
}

/* Animations */
@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive Design */
@media (max-width: 1024px) {
    .games-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    #hero h2 {
        font-size: 2.5rem;
    }

    .about-content {
        flex-direction: column;
        text-align: center;
    }

    .about-img {
        width: 300px;
    }
}

@media (max-width: 768px) {
    .about-content {
        flex-direction: column;
        text-align: center;
    }

    .about-img {
        margin: 0 auto;
    }

    header h1 {
        font-size: 1.75rem;
    }

    nav ul {
        flex-direction: column;
        text-align: center;
        gap: 12px;
    }

    nav {
        display: flex;
        flex-direction: column;
        align-items: center;
    }

    .social-links {
        justify-content: center;
        margin-top: 12px;
    }

    #hero {
        padding: 100px 20px 60px;
    }

    #hero h2 {
        font-size: 2rem;
    }

    .free-lesson-message {
        font-size: 1.2rem;
    }

    .games-grid {
        grid-template-columns: 1fr;
    }

    .videos-grid {
        grid-template-columns: 1fr;
    }

    .video-card {
        max-width: 100%;
    }

    .video-title {
        font-size: 1.1rem;
    }

    .video-description {
        font-size: 0.9rem;
    }

    .btn {
        padding: 12px 24px;
        font-size: 1rem;
    }

    .youtube-btn img {
        width: 24px;
        height: 17px;
    }

    .module-buttons {
        flex-direction: column;
    }

    .module-buttons a {
        width: 100%;
        margin-bottom: 8px;
    }
}

/* Print Styles */
@media print {
    header, footer {
        display: none;
    }

    .header-spacer {
        height: 0;
    }
}