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

:root {
    --primary-color: #45b6fe;
    --secondary-color: #daf0ff;
    --white: #ffffff;
    --text-dark: #1a1a1a;
    --text-gray: #666666;
    --border-color: #e0e0e0;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.15);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    overflow-x: hidden;
}

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

/* Navigation */
.navbar {
    background: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 1rem 0;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

.logo i {
    font-size: 1.8rem;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

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

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

.nav-buttons {
    display: flex;
    gap: 1rem;
}

.mobile-auth-buttons {
    display: none;
    flex-direction: column;
    gap: 1rem;
    padding: 1rem 0;
    border-top: 1px solid var(--border-color);
    margin-top: 1rem;
}

.mobile-auth-buttons button {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    border-radius: 3px;
}

/* Buttons */
.btn-primary, .btn-secondary, .btn-outline {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

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

.btn-primary:hover {
    background: #2ea3ed;
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

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

.btn-outline {
    background: transparent;
    color: var(--white);
    border: 2px solid var(--white);
}

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

.btn-large {
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, #2ea3ed 100%);
    color: var(--white);
    padding: 6rem 0 4rem;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1440 320"><path fill="%23ffffff" fill-opacity="0.1" d="M0,96L48,112C96,128,192,160,288,160C384,160,480,128,576,122.7C672,117,768,139,864,144C960,149,1056,139,1152,128C1248,117,1344,107,1392,101.3L1440,96L1440,320L1392,320C1344,320,1248,320,1152,320C1056,320,960,320,864,320C768,320,672,320,576,320C480,320,384,320,288,320C192,320,96,320,48,320L0,320Z"></path></svg>');
    background-size: cover;
    background-position: bottom;
    opacity: 0.3;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero .highlight {
    color: var(--secondary-color);
}

.hero p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    opacity: 0.95;
}

.search-bar {
    display: flex;
    align-items: center;
    background: var(--white);
    border-radius: 50px;
    padding: 0.5rem 1rem;
    max-width: 600px;
    margin: 0 auto 2rem;
    box-shadow: var(--shadow-lg);
}

.search-bar i {
    color: var(--text-gray);
    margin-right: 1rem;
}

.search-bar input {
    flex: 1;
    border: none;
    outline: none;
    font-size: 1rem;
    padding: 0.5rem;
    color: var(--text-dark);
}

.search-bar button {
    padding: 0.75rem 2rem;
    border-radius: 50px;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-bottom: 3rem;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 4rem;
    margin-top: 3rem;
}

.stat h3 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.stat p {
    font-size: 1rem;
    opacity: 0.9;
}

/* Section Header */
.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-header h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.section-header p {
    font-size: 1.1rem;
    color: var(--text-gray);
}

/* Categories Section */
.categories {
    padding: 5rem 0;
    background: var(--secondary-color);
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 2rem;
}

.category-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    transition: all 0.3s;
    cursor: pointer;
}

.category-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.category-card.highlighted {
    background: var(--primary-color);
    transform: translateY(-10px) scale(1.05);
    box-shadow: 0 15px 40px rgba(69, 182, 254, 0.4);
}

.category-card.highlighted h3,
.category-card.highlighted p {
    color: var(--white);
}

.category-card.highlighted .category-icon {
    background: var(--white);
}

.category-card.highlighted .category-icon i {
    color: var(--primary-color);
}

.category-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--primary-color), #2ea3ed);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
}

.category-icon i {
    font-size: 2rem;
    color: var(--white);
}

.category-card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
}

.category-card p {
    color: var(--text-gray);
}

/* Courses Section */
.courses {
    padding: 5rem 0;
    background: var(--white);
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
}

.course-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s;
}

.course-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.course-image {
    position: relative;
    width: 100%;
    height: 200px;
    overflow: hidden;
}

.course-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s;
}

.course-card:hover .course-image img {
    transform: scale(1.1);
}

.course-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--primary-color);
    color: var(--white);
    padding: 0.4rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
}

.course-content {
    padding: 1.5rem;
}

.course-category {
    color: var(--primary-color);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.course-content h3 {
    font-size: 1.3rem;
    margin-bottom: 0.75rem;
    color: var(--text-dark);
}

.course-content p {
    color: var(--text-gray);
    margin-bottom: 1rem;
    font-size: 0.95rem;
}

.course-instructor {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.course-instructor img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
}

.course-instructor span {
    font-size: 0.95rem;
    color: var(--text-dark);
}

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

.rating {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.rating i {
    color: #ffc107;
}

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

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

/* Why Choose Section */
.why-choose {
    padding: 5rem 0;
    background: var(--secondary-color);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    transition: all 0.3s;
}

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

.feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--primary-color), #2ea3ed);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.feature-icon i {
    font-size: 2rem;
    color: var(--white);
}

.feature-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

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

/* Testimonials Section */
.testimonials {
    padding: 5rem 0;
    background: var(--white);
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
}

.testimonial-card {
    background: var(--secondary-color);
    padding: 2rem;
    border-radius: 12px;
    transition: all 0.3s;
}

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

.stars {
    display: flex;
    gap: 0.3rem;
    margin-bottom: 1rem;
}

.stars i {
    color: #ffc107;
}

.testimonial-card p {
    color: var(--text-dark);
    margin-bottom: 1.5rem;
    line-height: 1.7;
    font-style: italic;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.testimonial-author img {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    border: 3px solid var(--white);
}

.testimonial-author h4 {
    color: var(--text-dark);
    margin-bottom: 0.25rem;
}

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

/* Footer */
.footer {
    background: var(--text-dark);
    color: var(--white);
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.footer-logo i {
    font-size: 1.8rem;
}

.footer-section p {
    color: #cccccc;
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: var(--primary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    transition: all 0.3s;
}

.social-links a:hover {
    background: var(--white);
    color: var(--primary-color);
    transform: translateY(-3px);
}

.footer-section h3 {
    margin-bottom: 1.5rem;
    color: var(--white);
    font-size: 1.2rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.75rem;
}

.footer-section ul li a {
    color: #cccccc;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section ul li a:hover {
    color: var(--primary-color);
}

.contact-info li {
    display: flex;
    align-items: center;
    gap: 1rem;
    color: #cccccc;
}

.contact-info i {
    color: var(--primary-color);
    width: 20px;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #444444;
    color: #cccccc;
}

/* Responsive Design */
@media (max-width: 968px) {
    .nav-links {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 1rem 0;
        box-shadow: var(--shadow);
        display: none;
    }

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

    .nav-links a {
        padding: 0.75rem 2rem;
    }

    .mobile-auth-buttons {
        display: flex;
        padding: 1rem 2rem;
    }

    .hamburger {
        display: flex;
    }

    .hero h1 {
        font-size: 2.2rem;
    }

    .hero p {
        font-size: 1.1rem;
    }

    .hero-stats {
        gap: 2rem;
    }

    .stat h3 {
        font-size: 2rem;
    }

    .courses-grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    }
}

@media (max-width: 768px) {
    .hero {
        padding: 4rem 0 3rem;
    }

    .hero h1 {
        font-size: 1.8rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .btn-large {
        width: 100%;
        max-width: 300px;
    }

    .search-bar {
        flex-direction: column;
        border-radius: 12px;
        padding: 1rem;
    }

    .search-bar input {
        width: 100%;
        margin-bottom: 1rem;
    }

    .search-bar button {
        width: 100%;
    }

    .hero-stats {
        flex-direction: column;
        gap: 1.5rem;
    }

    .section-header h2 {
        font-size: 2rem;
    }

    .categories-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        gap: 1rem;
    }

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

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

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

    .nav-buttons {
        display: none;
    }
}

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

    .category-icon {
        width: 60px;
        height: 60px;
    }

    .category-icon i {
        font-size: 1.5rem;
    }

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