/* ===== ROOT & GENERAL STYLES ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --accent-color: #f59e0b;
    --light-bg: #f3f4f6;
    --dark-text: #1f2937;
    --light-text: #6b7280;
    --white: #ffffff;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --radius: 8px;
}

html {
    scroll-behavior: smooth;
}

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

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

/* ===== NAVIGATION ===== */
.navbar {
    background: linear-gradient(135deg,#1f2937 0%, #111827 100%);
    box-shadow: 0 8px 16px rgba(0, 191, 255, 0.3);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo {
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--white);
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-icon {
    font-size: 2rem;
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-5px);
    }
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

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

.nav-links a:hover {
    color: var(--accent-color);
    text-shadow: 0 0 8px rgba(245, 158, 11, 0.5);
}

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

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--white);
    margin: 5px 0;
    transition: all 0.3s ease;
}

/* ===== HERO SECTION ===== */
.hero {
    background: whitesmoke !important;
    color: #1d4ed8 !important;
    padding: 100px 20px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: none;
    pointer-events: none;
}

.hero .container {
    position: relative;
    z-index: 1;
}

.page-header,
.course-header {
    background: whitesmoke !important;
    color: #1d4ed8 !important;
    padding: 60px 20px;
    text-align: center;
}

.page-header h1,
.page-header p,
.course-header h1,
.course-header p {
    color: #1d4ed8 !important;
}

.page-header {
    border-radius: 10px;
}

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    animation: fadeInDown 0.8s ease;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-content p {
    font-size: 1.3rem;
    margin-bottom: 2rem;
    opacity: 0.95;
    animation: fadeInUp 0.8s ease;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.1);
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ===== BUTTONS ===== */
.btn {
    padding: 12px 30px;
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
}

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

.btn-primary:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: 0 8px 12px rgba(16, 185, 129, 0.4);
}

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

.btn-secondary:hover {
    background-color: #f59e0b;
    transform: translateY(-2px);
    box-shadow: 0 8px 12px rgba(245, 158, 11, 0.4);
}

/* ===== ABOUT SECTION ===== */
.about {
    padding: 80px 20px;
    background: #4169E1;
    position: relative;
}

.about h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--white);
    position: relative;
    z-index: 1;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.1);
}

.about-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    position: relative;
    z-index: 1;
}

.about-item {
    background: var(--white);
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border-top: 4px solid #4169E1;
}

.about-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.15);
}

.about-item h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

.about-item p {
    color: var(--light-text);
    line-height: 1.8;
}

/* ===== COURSES SECTION ===== */
.courses {
    padding: 80px 20px;
    background: #f9fafb;
    position: relative;
}

.courses h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #4169E1;
    font-weight: 700;
}

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

.course-card {
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 2.5rem;
    text-align: center;
    transition: all 0.3s ease;
    border-top: 4px solid var(--primary-color);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.course-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s ease;
    pointer-events: none;
}

.course-card:hover::before {
    left: 100%;
}

.course-card[data-course="java"] {
    border-top-color: #FF6B35;
}

.course-card[data-course="android"] {
    border-top-color: #3DDC84;
}

.course-card[data-course="python"] {
    border-top-color: #306998;
}

.course-card[data-course="react"] {
    border-top-color: #61DAFB;
}

.course-card[data-course="nodejs"] {
    border-top-color: #68A063;
}

.course-card[data-course="web-development"] {
    border-top-color: #555555;
}

.course-card[data-course="numpy"] {
    border-top-color: #4BACC6;
}

.course-card[data-course="pandas"] {
    border-top-color: #150458;
}

.course-card[data-course="pyspark"] {
    border-top-color: #E25D30;
}

.course-card[data-course="ai-fundamentals"] {
    border-top-color: #10B981;
}

.course-card[data-course="machine-learning"] {
    border-top-color: #8B5CF6;
}

.course-card[data-course="deep-learning"] {
    border-top-color: #F59E0B;
}

.course-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.course-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

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

.course-card p {
    color: var(--light-text);
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

/* ===== FEATURES SECTION ===== */
.features {
    padding: 80px 20px;
    background: #4169E1;
    position: relative;
}

.features h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 15px;
    color: var(--white);
    font-weight: 700;
}

.features-subtitle {
    text-align: center;
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 40px;
}

.features-grid-3col {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.feature-item-large {
    background: var(--white);
    padding: 30px;
    border-radius: var(--radius);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.08);
    border-top: 4px solid #4169E1;
    transition: all 0.3s ease;
    position: relative;
}

.feature-item-large:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 35px rgba(65, 105, 225, 0.15);
}

.feature-icon {
    font-size: 3.5rem;
    margin-bottom: 15px;
}

.feature-item-large h3 {
    color: #4169E1;
    margin-bottom: 15px;
    font-size: 1.4rem;
    font-weight: 700;
}

.feature-item-large p {
    color: var(--light-text);
    margin-bottom: 20px;
    line-height: 1.7;
}

.feature-list {
    list-style: none;
    padding: 0;
}

.feature-list li {
    color: #555;
    padding: 8px 0;
    border-bottom: 1px solid #eee;
    font-size: 0.95rem;
}

.feature-list li:last-child {
    border-bottom: none;
}

.feature-list li:before {
    color: var(--accent-color);
    margin-right: 10px;
    font-weight: bold;
}

/* Old feature-item styles kept for reference */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.feature-item {
    background: var(--white);
    padding: 2rem;
    border-radius: var(--radius);
    text-align: center;
    border-left: 4px solid var(--accent-color);
}

.feature-number {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
    font-weight: bold;
    font-size: 1.5rem;
}

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

.feature-item p {
    color: var(--light-text);
}

/* ===== STATISTICS SECTION ===== */
.stats {
    background: #4169E1;
    color: var(--white);
    padding: 60px 20px;
}

.stats .container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    text-align: center;
}

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

.stat-item p {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* ===== CONTACT SECTION ===== */
.contact {
    padding: 80px 20px;
    background: #f9fafb;
    position: relative;
}

.contact h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #4169E1;
    font-weight: 700;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
}

.contact-form h3,
.contact-info h3 {
    margin-bottom: 1.5rem;
    color: #4169E1;
    font-size: 1.5rem;
    font-weight: 700;
}

.contact-form form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.contact-form input,
.contact-form textarea {
    padding: 12px;
    border: 1px solid #e5e7eb;
    border-radius: var(--radius);
    font-family: inherit;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: #4169E1;
    box-shadow: 0 0 0 3px rgba(65, 105, 225, 0.1);
}

.info-item {
    margin-bottom: 2rem;
}

.info-item strong {
    display: block;
    color: var(--dark-text);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.info-item p {
    color: var(--light-text);
    line-height: 1.8;
}

/* ===== FOOTER ===== */
.footer {
    background: linear-gradient(135deg, #1f2937 0%, #111827 100%);
    color: var(--white);
    padding: 3rem 20px 1rem;
    margin-top: 2rem;
    position: relative;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, #4169E1, transparent);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

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

.footer-section a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.3s ease;
    display: block;
    margin-bottom: 0.5rem;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #374151;
    color: #9ca3af;
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-links {
        position: absolute;
        top: 60px;
        left: 0;
        right: 0;
        flex-direction: column;
        background-color: rgb(23, 33, 37);
        gap: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
        box-shadow: var(--shadow);
    }

    .nav-links.active {
        max-height: 400px;
    }

    .nav-links li {
        padding: 1rem 20px;
        border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    }

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

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

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

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

    .about h2,
    .courses h2,
    .features h2,
    .contact h2 {
        font-size: 2rem;
    }

    .features-grid-3col {
        grid-template-columns: 1fr;
    }

    .feature-item-large {
        padding: 20px;
    }

    .feature-icon {
        font-size: 2.5rem;
    }
}

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

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

    .course-card,
    .about-item,
    .feature-item {
        padding: 1.5rem;
    }
}