:root {
    --primary-dark: #0a0a0a;
    --secondary-dark: #1a1a1a;
    --neon-blue: #00e5ff;
    --text-light: #e0e0e0;
    --text-highlight: #42a5f5;
    --accent-orange: #ff9800;

    --heading-font: 'Montserrat', sans-serif;
    --body-font: 'Open Sans', sans-serif;
    --border-radius: 8px;
    --box-shadow: 0 4px 10px rgba(0, 229, 255, 0.2);
    --hover-shadow: 0 8px 20px rgba(0, 229, 255, 0.4);
}

.friend-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
    justify-content: center;
    max-width: 900px;
    margin: 0 auto;
}

@media (min-width: 600px) {
    .friend-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

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

body {
    font-family: var(--body-font);
    line-height: 1.6;
    color: var(--text-light);
    background-color: var(--primary-dark);
    scroll-behavior: smooth;
}

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

h1, h2, h3 {
    font-family: var(--heading-font);
    color: var(--text-light);
    margin-bottom: 20px;
}

a {
    color: var(--neon-blue);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--text-highlight);
}

.main-header {
    background-color: var(--primary-dark);
    padding: 20px 0;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.4);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid rgba(0, 229, 255, 0.2);
}

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

.main-header .logo {
    margin: 0;
    font-size: 1.8em;
    font-weight: 700;
    color: var(--neon-blue);
    text-shadow: 0 0 5px var(--neon-blue);
}

.main-nav ul {
    list-style: none;
    display: flex;
}

.main-nav li {
    margin-left: 30px;
}

.main-nav a {
    font-weight: 600;
    font-size: 1.1em;
    padding: 5px 0;
    position: relative;
    color: var(--text-light);
}

.main-nav a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    background: var(--neon-blue);
    left: 0;
    bottom: 0;
    transition: width 0.3s ease;
}

.main-nav a:hover::after {
    width: 100%;
}

.section {
    padding: 80px 0;
    text-align: center;
}

.section:nth-of-type(even) {
    background-color: var(--secondary-dark);
}

.section-title {
    font-size: 2.5em;
    margin-bottom: 50px;
    position: relative;
    display: inline-block;
    color: var(--neon-blue);
    text-shadow: 0 0 8px rgba(0, 229, 255, 0.5);
}

.section-title::after {
    content: '';
    position: absolute;
    width: 60px;
    height: 4px;
    background: var(--text-highlight);
    left: 50%;
    transform: translateX(-50%);
    bottom: -15px;
    border-radius: 2px;
}

.hero-section {
    background: linear-gradient(135deg, var(--primary-dark) 0%, #001f3f 100%);
    color: var(--text-light);
    padding: 100px 0;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: radial-gradient(circle at 10% 20%, rgba(0, 229, 255, 0.05) 0%, transparent 50%),
                      radial-gradient(circle at 90% 80%, rgba(0, 229, 255, 0.05) 0%, transparent 50%);
    z-index: 1;
    pointer-events: none;
}

.hero-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    position: relative;
    z-index: 2;
}

.profile-pic {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    border: 5px solid var(--neon-blue);
    box-shadow: 0 0 15px var(--neon-blue);
}

.hero-content h2 {
    font-size: 3.5em;
    margin-bottom: 10px;
    color: var(--text-light);
    font-weight: 700;
    text-shadow: 0 0 10px rgba(0, 229, 255, 0.7);
}

.hero-content h2 .highlight {
    color: var(--neon-blue);
}

.hero-content .subtitle {
    font-size: 1.5em;
    color: var(--text-highlight);
    font-weight: 600;
    margin-bottom: 20px;
}

.hero-content .bio {
    max-width: 700px;
    font-size: 1.1em;
    line-height: 1.8;
    color: var(--text-light);
}

.courses-section {
    background-color: var(--primary-dark);
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.course-card {
    background-color: var(--secondary-dark);
    border-radius: var(--border-radius);
    padding: 30px;
    box-shadow: var(--box-shadow);
    transition: transform 0.3s ease-in-out, box-shadow 0.3s ease-in-out;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: space-between;
    color: var(--text-light);
    border: 1px solid rgba(0, 229, 255, 0.1);
}

.course-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--hover-shadow);
}

.course-card img {
    width: 80px;
    height: 80px;
    border-radius: var(--border-radius);
    object-fit: cover;
    box-shadow: 0 0 10px rgba(0, 229, 255, 0.5);
}

.course-card h3 {
    font-size: 1.6em;
    margin-bottom: 10px;
    color: var(--neon-blue);
}

.course-card .instructor {
    font-size: 0.9em;
    color: var(--text-highlight);
    margin-bottom: 15px;
}

.course-card p {
    font-size: 1em;
    color: var(--text-light);
    margin-bottom: 20px;
    flex-grow: 1;
}

.progress-bar-container {
    width: 100%;
    background-color: #333;
    border-radius: 5px;
    height: 10px;
    margin-top: 15px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: var(--neon-blue);
    border-radius: 5px;
    text-align: center;
    color: var(--primary-dark);
    font-size: 0.7em;
    line-height: 10px;
    transition: width 1s ease-out;
    box-shadow: 0 0 5px var(--neon-blue);
}

.friends-section {
    background-color: var(--secondary-dark);
}

.friends-section .friend-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 30px;
    justify-content: center;
    max-width: 900px;
    margin: 0 auto;
}

@media (min-width: 600px) {
    .friends-section .friend-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

.friend-card {
    background-color: var(--secondary-dark);
    border-radius: var(--border-radius);
    padding: 20px;
    box-shadow: var(--box-shadow);
    transition: transform 0.3s ease-in-out, box-shadow 0.3s ease-in-out;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    color: var(--text-light);
    border: 1px solid rgba(0, 229, 255, 0.1);
    width: 100%;
    max-width: 300px;
    margin-left: auto;
    margin-right: auto;
}

.friend-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--hover-shadow);
}

.website-link-preview {
    display: block;
    width: 100%;
    height: 180px;
    overflow: hidden;
    border: 1px solid var(--neon-blue);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    position: relative;
    background-color: var(--primary-dark);
    margin-bottom: 15px;
}

.website-link-preview iframe {
    width: 100%;
    height: 100%;
    border: none;
    transform: scale(0.3);
    transform-origin: 0 0;
    pointer-events: none;
    position: absolute;
    top: 0;
    left: 0;
}

.friend-card h3 {
    font-size: 1.8em;
    margin-bottom: 8px;
    color: var(--neon-blue);
}

.friend-card .shared-courses {
    font-size: 0.95em;
    color: var(--text-highlight);
    margin-bottom: 10px;
}

.friend-card .fun-fact {
    font-style: italic;
    color: var(--text-light);
    font-size: 0.9em;
}

.main-footer {
    background-color: var(--primary-dark);
    color: var(--text-light);
    padding: 40px 0;
    text-align: center;
    font-size: 0.9em;
    border-top: 1px solid rgba(0, 229, 255, 0.2);
}

.main-footer .social-links {
    margin-top: 15px;
}

.main-footer .social-links a {
    color: var(--neon-blue);
    font-size: 1.5em;
    margin: 0 10px;
    transition: color 0.3s ease, text-shadow 0.3s ease;
}

.main-footer .social-links a:hover {
    color: var(--text-highlight);
    text-shadow: 0 0 10px var(--neon-blue);
}

.fade-in-up {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in-up.active {
    opacity: 1;
    transform: translateY(0);
}

.fade-in-up.delay-1 { transition-delay: 0.2s; }
.fade-in-up.delay-2 { transition-delay: 0.4s; }
.fade-in-up.delay-3 { transition-delay: 0.6s; }

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

.course-card.delay-1, .friend-card.delay-1 { transition-delay: 0.1s; }
.course-card.delay-2, .friend-card.delay-2 { transition-delay: 0.2s; }
.course-card.delay-3, .friend-card.delay-3 { transition-delay: 0.3s; }

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

    .main-nav ul {
        margin-top: 15px;
        flex-wrap: wrap;
        justify-content: center;
    }

    .main-nav li {
        margin: 0 15px 10px;
    }

    .section {
        padding: 60px 0;
    }

    .hero-content h2 {
        font-size: 2.5em;
    }

    .hero-content .subtitle {
        font-size: 1.2em;
    }

    .section-title {
        font-size: 2em;
    }

    .course-card, .friend-card {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .main-header .logo {
        font-size: 1.5em;
    }

    .main-nav li {
        margin: 0 10px 5px;
    }

    .hero-content h2 {
        font-size: 2em;
    }

    .hero-content .subtitle {
        font-size: 1em;
    }

    .section-title {
        font-size: 1.8em;
    }

    .profile-pic {
        width: 150px;
        height: 150px;
    }

    .course-card h3, .friend-card h3 {
        font-size: 1.4em;
    }
}