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

:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --text-color: #333;
    --light-bg: #f8f9fa;
    --white: #ffffff;
    --gray: #6c757d;
    --light-gray: #e9ecef;
    --dark-gray: #495057;
    --success-color: #28a745;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 20px rgba(0, 0, 0, 0.15);
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--white);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

section {
    padding: 80px 0;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 20px;
    color: var(--primary-color);
}

.section-subtitle {
    text-align: center;
    font-size: 1.2rem;
    color: var(--gray);
    margin-bottom: 40px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

/* Navigation */
.navbar {
    background-color: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 15px 0;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

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

.nav-menu a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: var(--secondary-color);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--primary-color);
    transition: all 0.3s;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--primary-color) 100%);
    color: var(--white);
    padding: 120px 0;
    text-align: center;
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 20px;
    font-weight: 500;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 40px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    opacity: 0.95;
}

.cta-button {
    display: inline-block;
    padding: 15px 40px;
    background-color: var(--accent-color);
    color: var(--white);
    text-decoration: none;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 600;
    transition: all 0.3s;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.cta-button:hover {
    background-color: #c0392b;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

/* About Section */
.about {
    background-color: var(--light-bg);
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-text h3 {
    font-size: 1.8rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.about-text p {
    font-size: 1.1rem;
    margin-bottom: 20px;
    line-height: 1.8;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.stat-item {
    text-align: center;
    padding: 20px;
    background-color: var(--white);
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 10px;
}

.stat-label {
    display: block;
    font-size: 1rem;
    color: var(--gray);
}

/* Experience Section */
.experience-timeline {
    max-width: 800px;
    margin: 0 auto;
}

.timeline-item {
    display: grid;
    grid-template-columns: 150px 1fr;
    gap: 30px;
    margin-bottom: 40px;
    position: relative;
}

.timeline-item:not(:last-child)::after {
    content: '';
    position: absolute;
    left: 75px;
    top: 60px;
    bottom: -40px;
    width: 2px;
    background-color: var(--light-gray);
}

.timeline-year {
    font-weight: 700;
    color: var(--secondary-color);
    font-size: 1.1rem;
}

.timeline-content {
    background-color: var(--white);
    padding: 25px;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.timeline-content h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 1.5rem;
}

.timeline-content p {
    color: var(--dark-gray);
    line-height: 1.7;
}

/* Teaching Focus Section */
.teaching-focus {
    background-color: var(--light-bg);
}

.focus-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.focus-card {
    background-color: var(--white);
    padding: 35px;
    border-radius: 10px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: all 0.3s;
}

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

.focus-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.focus-card h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 1.5rem;
}

.focus-card p {
    color: var(--dark-gray);
    line-height: 1.7;
}

/* Materials Section */
.materials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
    max-width: 1000px;
    margin: 0 auto;
}

.material-card {
    background-color: var(--light-bg);
    padding: 35px;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.material-card h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.material-card ul {
    list-style: none;
}

.material-card li {
    margin-bottom: 15px;
    padding-left: 25px;
    position: relative;
    line-height: 1.7;
}

.material-card li::before {
    content: '📚';
    position: absolute;
    left: 0;
    top: 0;
}

.material-card strong {
    color: var(--secondary-color);
}

/* Intro Video Section */
.intro-video {
    background-color: var(--light-bg);
}

.video-container {
    max-width: 800px;
    margin: 0 auto;
}

.video-placeholder {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    padding: 100px 40px;
    border-radius: 15px;
    text-align: center;
    color: var(--white);
}

.video-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.video-placeholder p {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.video-placeholder small {
    font-size: 1rem;
    opacity: 0.9;
}

/* Class Types Section */
.class-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.class-card {
    background-color: var(--white);
    padding: 35px;
    border-radius: 10px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: all 0.3s;
    border-top: 4px solid var(--secondary-color);
}

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

.class-card h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 1.5rem;
}

.class-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.class-card > p {
    color: var(--dark-gray);
    margin-bottom: 20px;
    line-height: 1.7;
}

.class-features {
    list-style: none;
    text-align: left;
}

.class-features li {
    padding: 8px 0;
    color: var(--dark-gray);
}

/* Testimonials Section */
.testimonials {
    background-color: var(--light-bg);
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.testimonial-card {
    background-color: var(--white);
    padding: 30px;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.testimonial-stars {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: #f39c12;
}

.testimonial-text {
    font-style: italic;
    margin-bottom: 20px;
    line-height: 1.7;
    color: var(--dark-gray);
}

.testimonial-author {
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.testimonial-author strong {
    color: var(--primary-color);
}

.testimonial-author span {
    color: var(--gray);
    font-size: 0.9rem;
}

/* FAQ Section */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background-color: var(--white);
    margin-bottom: 15px;
    border-radius: 10px;
    box-shadow: var(--shadow);
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 20px;
    background-color: var(--white);
    border: none;
    text-align: left;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--primary-color);
    transition: background-color 0.3s;
}

.faq-question:hover {
    background-color: var(--light-bg);
}

.faq-toggle {
    font-size: 1.5rem;
    font-weight: 400;
    color: var(--secondary-color);
    transition: transform 0.3s;
}

.faq-item.active .faq-toggle {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

.faq-answer p {
    padding: 0 20px 20px;
    color: var(--dark-gray);
    line-height: 1.7;
}

/* Contact Section */
.contact {
    background-color: var(--light-bg);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 50px;
    max-width: 1100px;
    margin: 0 auto;
}

.contact-info {
    background-color: var(--white);
    padding: 35px;
    border-radius: 10px;
    box-shadow: var(--shadow);
    height: fit-content;
}

.contact-info h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.contact-info p {
    margin-bottom: 15px;
    color: var(--dark-gray);
    line-height: 1.7;
}

.support-note {
    margin-top: 30px;
    padding: 20px;
    background-color: var(--light-bg);
    border-radius: 8px;
    border-left: 4px solid var(--secondary-color);
}

.support-note strong {
    color: var(--primary-color);
    display: block;
    margin-bottom: 10px;
}

.note-text {
    font-size: 0.9rem;
    color: var(--gray);
    margin-top: 15px;
}

.contact-form-wrapper {
    background-color: var(--white);
    padding: 35px;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--primary-color);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--light-gray);
    border-radius: 5px;
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--secondary-color);
}

.form-group input.error,
.form-group select.error,
.form-group textarea.error {
    border-color: var(--accent-color);
}

.error-message {
    display: block;
    color: var(--accent-color);
    font-size: 0.875rem;
    margin-top: 5px;
    min-height: 20px;
}

.submit-button {
    width: 100%;
    padding: 15px;
    background-color: var(--secondary-color);
    color: var(--white);
    border: none;
    border-radius: 5px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.submit-button:hover {
    background-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.success-message {
    display: none;
    padding: 15px;
    background-color: var(--success-color);
    color: var(--white);
    border-radius: 5px;
    margin-top: 20px;
    text-align: center;
}

.success-message.show {
    display: block;
}

/* Footer */
.footer {
    background-color: var(--primary-color);
    color: var(--white);
    text-align: center;
    padding: 30px 0;
}

.footer p {
    margin-bottom: 10px;
    opacity: 0.9;
}

/* Responsive Design */
@media (max-width: 992px) {
    .section-title {
        font-size: 2rem;
    }

    .contact-content {
        grid-template-columns: 1fr;
    }

    .timeline-item {
        grid-template-columns: 120px 1fr;
        gap: 20px;
    }

    .timeline-item:not(:last-child)::after {
        left: 60px;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--white);
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow);
    }

    .nav-menu.active {
        display: flex;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .hero-content h1 {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    section {
        padding: 60px 0;
    }

    .materials-grid,
    .focus-grid,
    .class-grid,
    .testimonials-grid {
        grid-template-columns: 1fr;
    }

    .timeline-item {
        grid-template-columns: 1fr;
    }

    .timeline-item:not(:last-child)::after {
        display: none;
    }

    .about-stats {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-content h1 {
        font-size: 1.5rem;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .cta-button {
        padding: 12px 30px;
        font-size: 1rem;
    }

    .container {
        padding: 0 15px;
    }
}