:root {
    --primary-color: #0a192f;
    --secondary-color: #112240;
    --accent-color: #64ffda;
    --text-color: #8892b0;
    --light-text: #ccd6f6;
    --background-color: #0a192f;
    --card-bg: #112240;
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', 'Segoe UI', sans-serif;
}

body {
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
}

/* Navbar Styles */
.navbar {
    background-color: rgba(10, 25, 47, 0.85);
    backdrop-filter: blur(10px);
    padding: 1.2rem 5%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 10px 30px -10px rgba(2,12,27,0.7);
}

.logo h1 {
    color: var(--accent-color);
    font-size: 1.5rem;
    font-weight: 700;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 1rem;
}

.nav-links li a {
    color: var(--light-text);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: var(--transition);
    font-weight: 500;
}

.nav-links li a:hover,
.nav-links li a.active {
    color: var(--accent-color);
}

/* Hero Section */
.hero {
    background: linear-gradient(rgba(10, 25, 47, 0.9), rgba(10, 25, 47, 0.9)),
                url('../images/hero-bg.jpg');
    background-size: cover;
    background-position: center;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--light-text);
    padding: 0 1rem;
    margin-top: 0;
}

.hero-content h1 {
    font-size: 4rem;
    margin-bottom: 1.5rem;
    background: linear-gradient(45deg, var(--accent-color), var(--light-text));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-content p {
    font-size: 1.4rem;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.cta-button {
    display: inline-block;
    padding: 1rem 2rem;
    background-color: transparent;
    color: var(--accent-color);
    text-decoration: none;
    border: 2px solid var(--accent-color);
    border-radius: 4px;
    transition: var(--transition);
    font-weight: 600;
    letter-spacing: 1px;
}

.cta-button:hover {
    background-color: rgba(100, 255, 218, 0.1);
    transform: translateY(-3px);
}

/* Features Section */
.features {
    padding: 8rem 5%;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2.5rem;
    background-color: var(--secondary-color);
}

.feature-card {
    text-align: center;
    padding: 2.5rem;
    border-radius: 12px;
    background-color: var(--card-bg);
    box-shadow: 0 10px 30px -15px rgba(2,12,27,0.7);
    transition: var(--transition);
    border: 1px solid rgba(100, 255, 218, 0.1);
}

.feature-card:hover {
    transform: translateY(-10px);
    border-color: var(--accent-color);
}

.feature-card i {
    font-size: 3rem;
    color: var(--accent-color);
    margin-bottom: 1.5rem;
}

.feature-card h3 {
    color: var(--light-text);
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

/* Popular Courses Section */
.popular-courses {
    padding: 8rem 5%;
    background-color: var(--background-color);
}

.popular-courses h2 {
    text-align: center;
    margin-bottom: 4rem;
    color: var(--light-text);
    font-size: 2.5rem;
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2.5rem;
}

.course-card {
    background-color: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 10px 30px -15px rgba(2,12,27,0.7);
    transition: var(--transition);
    border: 1px solid rgba(100, 255, 218, 0.1);
}

.course-card:hover {
    transform: translateY(-10px);
    border-color: var(--accent-color);
}

.course-card img {
    width: 100%;
    height: 220px;
    object-fit: cover;
}

.course-card h3 {
    padding: 1.5rem 1.5rem 0.5rem;
    color: var(--light-text);
    font-size: 1.4rem;
}

.course-card p {
    padding: 0 1.5rem 1.5rem;
    color: var(--text-color);
}

.course-link {
    display: inline-block;
    margin: 0 1.5rem 1.5rem;
    padding: 0.8rem 1.5rem;
    background-color: transparent;
    color: var(--accent-color);
    text-decoration: none;
    border: 2px solid var(--accent-color);
    border-radius: 4px;
    transition: var(--transition);
    font-weight: 600;
}

.course-link:hover {
    background-color: rgba(100, 255, 218, 0.1);
}

/* Footer */
footer {
    background-color: var(--secondary-color);
    color: var(--light-text);
    padding: 4rem 5% 1rem;
    border-top: 1px solid rgba(100, 255, 218, 0.1);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-section h4 {
    color: var(--accent-color);
    margin-bottom: 1.5rem;
    font-size: 1.2rem;
}

.social-links a {
    color: var(--light-text);
    margin-right: 1.5rem;
    font-size: 1.8rem;
    transition: var(--transition);
}

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

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(100, 255, 218, 0.1);
    color: var(--text-color);
}

/* Mobile Menu Button */
.mobile-menu-button {
    display: none;
    background: none;
    border: none;
    color: var(--accent-color);
    font-size: 1.5rem;
    cursor: pointer;
}

/* Responsive Design */
@media (max-width: 768px) {
    .navbar {
        padding: 1rem;
    }

    .mobile-menu-button {
        display: block;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: var(--secondary-color);
        padding: 1rem;
        flex-direction: column;
        text-align: center;
    }

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

    .hero-content h1 {
        font-size: 2.5rem;
    }

    .features {
        padding: 4rem 1rem;
    }

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