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

:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #1a1a1a;
    --bg-card: #252525;
    --text-primary: #ffffff;
    --text-secondary: #b0b0b0;
    --accent: #4a9eff;
    --accent-hover: #357abd;
    --border: #333333;
    --shadow: rgba(0, 0, 0, 0.5);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    padding: 2rem 0;
    position: sticky;
    top: 0;
    background-color: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border);
    animation: slideDown 0.5s ease-out;
}

@keyframes slideDown {
    from {
        transform: translateY(-100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

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

.name {
    font-size: 1.5rem;
    font-weight: 600;
    background: linear-gradient(135deg, #4a9eff 0%, #357abd 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.video-btn {
    background: var(--accent);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(74, 158, 255, 0.3);
}

.video-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(74, 158, 255, 0.4);
}

main {
    flex: 1;
    padding: 2rem 0;
}

section {
    margin-bottom: 4rem;
    animation: fadeInUp 0.6s ease-out;
    animation-fill-mode: both;
}

section:nth-child(1) { animation-delay: 0.1s; }
section:nth-child(2) { animation-delay: 0.2s; }
section:nth-child(3) { animation-delay: 0.3s; }
section:nth-child(4) { animation-delay: 0.4s; }
section:nth-child(5) { animation-delay: 0.5s; }

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

.hero {
    text-align: center;
    padding: 2rem 0;
}

.profile-info {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    align-items: center;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.1rem;
}

.icon {
    font-size: 1.2rem;
}

h2 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.about p {
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: 12px;
    line-height: 1.8;
    color: var(--text-secondary);
    border: 1px solid var(--border);
    transition: all 0.3s ease;
}

.about p:hover {
    border-color: var(--accent);
    box-shadow: 0 4px 20px var(--shadow);
    transform: translateY(-2px);
}

.course-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.course-item {
    background: var(--bg-secondary);
    border-radius: 12px;
    border: 1px solid var(--border);
    overflow: hidden;
    transition: all 0.3s ease;
}

.course-header {
    width: 100%;
    padding: 1.5rem;
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    text-align: left;
    transition: all 0.3s ease;
}

.course-header:hover {
    background: var(--bg-card);
}

.course-title {
    flex: 1;
}

.arrow {
    font-size: 0.8rem;
    transition: transform 0.3s ease;
    color: var(--accent);
}

.course-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
    background: var(--bg-card);
}

.course-content p {
    padding: 1.5rem;
    margin: 0;
    color: var(--text-secondary);
    line-height: 1.6;
    border-top: 1px solid var(--border);
}

.course-item.active .course-content {
    max-height: 200px;
}

.course-item.active {
    border-color: var(--accent);
    box-shadow: 0 4px 15px rgba(74, 158, 255, 0.2);
}

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

.certificate-container {
    background: var(--bg-secondary);
    padding: 1rem;
    border-radius: 12px;
    text-align: center;
    border: 1px solid var(--border);
    overflow: hidden;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.certificate-container:hover {
    border-color: var(--accent);
    box-shadow: 0 4px 20px var(--shadow);
    transform: translateY(-2px);
}

.certificate-img {
    width: 100%;
    height: auto;
    border-radius: 8px;
    transition: transform 0.3s ease;
    object-fit: contain;
}

.certificate-img:hover {
    transform: scale(1.05);
}

.interest-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.tag {
    background: var(--bg-card);
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    font-weight: 500;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.tag::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: var(--accent);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: all 0.5s ease;
    z-index: -1;
}

.tag:hover {
    color: white;
    border-color: var(--accent);
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(74, 158, 255, 0.3);
}

.tag:hover::before {
    width: 200%;
    height: 200%;
}

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

.project-card {
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), #357abd);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.3s ease;
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px var(--shadow);
    border-color: var(--accent);
}

.project-card:hover::before {
    transform: scaleX(1);
}

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

.project-card p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.project-link {
    display: inline-block;
    background: var(--accent);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

.project-link:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(74, 158, 255, 0.3);
}

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

.skill-card {
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.skill-card::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), #357abd);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.3s ease;
}

.skill-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px var(--shadow);
    border-color: var(--accent);
}

.skill-card:hover::after {
    transform: scaleX(1);
}

.skill-card h3 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.skill-card p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Tool list styling */
.tool-list {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.tool-item {
    display: flex;
    flex-direction: column;
    padding: 0.8rem 1rem;
    background: var(--bg-card);
    border-radius: 8px;
    border-left: 3px solid var(--accent);
    transition: all 0.3s ease;
}

.tool-item:hover {
    transform: translateX(5px);
    background: rgba(74, 158, 255, 0.1);
}

.tool-name {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 1rem;
}

.tool-desc {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 0.2rem;
}

/* OS Grid styling */
.os-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.os-card {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-card) 100%);
    padding: 2rem;
    border-radius: 16px;
    border: 2px solid var(--accent);
    text-align: center;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(74, 158, 255, 0.15);
}

.os-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--accent), #357abd);
}

.os-card:hover {
    transform: translateY(-8px);
    border-color: #357abd;
    box-shadow: 0 15px 40px rgba(74, 158, 255, 0.3);
}

.os-icon {
    font-size: 3rem;
    display: block;
    margin-bottom: 1rem;
}

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

.os-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    .os-grid {
        grid-template-columns: 1fr;
    }
}

.personal-skills-container {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    justify-content: center;
}

.personal-skill-badge {
    background: linear-gradient(135deg, var(--bg-secondary), var(--bg-card));
    border: 2px solid var(--accent);
    border-radius: 20px;
    padding: 1.5rem 2rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    max-width: 500px;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.personal-skill-badge::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(74, 158, 255, 0.1) 0%, transparent 70%);
    transition: all 0.5s ease;
    opacity: 0;
}

.personal-skill-badge:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 10px 30px rgba(74, 158, 255, 0.3);
    border-color: #357abd;
}

.personal-skill-badge:hover::before {
    opacity: 1;
}

.badge-icon {
    font-size: 1.5rem;
}

.badge-content h4 {
    font-size: 1.1rem;
    color: var(--accent);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.badge-content p {
    color: var(--text-secondary);
    line-height: 1.5;
    margin: 0;
    font-size: 0.95rem;
}

/* Books Section */
.books-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.book-card {
    background: var(--bg-secondary);
    border-radius: 12px;
    border: 1px solid var(--border);
    overflow: hidden;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
    min-height: 0;
    -webkit-transform: translateZ(0);
    transform: translateZ(0);
}

.book-card:hover {
    border-color: var(--accent);
    box-shadow: 0 8px 30px var(--shadow);
    -webkit-transform: translateY(-5px);
    transform: translateY(-5px);
}

.book-image-container {
    width: 100%;
    padding: 1.5rem;
    background: var(--bg-card);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 320px;
}

.book-img {
    display: block;
    max-width: 100%;
    max-height: 280px;
    width: auto;
    height: auto;
    border-radius: 8px;
    -webkit-transition: transform 0.3s ease;
    transition: transform 0.3s ease;
}

.book-card:hover .book-img {
    -webkit-transform: scale(1.05);
    transform: scale(1.05);
}

.book-card h3 {
    font-size: 1.2rem;
    margin: 1.5rem 1.5rem 0.5rem 1.5rem;
    color: var(--text-primary);
}

.book-author {
    margin: 0 1.5rem;
    color: var(--accent);
    font-weight: 500;
    font-size: 0.95rem;
}

.book-description {
    padding: 1rem 1.5rem 1.5rem 1.5rem;
    flex-grow: 1;
    color: var(--text-secondary);
    line-height: 1.6;
}

@media (max-width: 768px) {
    .books-grid {
        grid-template-columns: 1fr;
    }

    .book-image-container {
        min-height: 280px;
    }

    .book-img {
        max-height: 240px;
    }
}

.quote-section {
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    padding: 6rem 2rem;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.quote-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent), transparent);
}

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

.quote-text {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
    line-height: 1.3;
    letter-spacing: -0.5px;
}

.quote-author {
    font-size: 1.2rem;
    color: var(--accent);
    font-weight: 400;
    font-style: italic;
}

footer {
    text-align: center;
    padding: 2rem 0;
    border-top: 1px solid var(--border);
    color: var(--text-secondary);
}

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    .name {
        font-size: 1.3rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    .course-header {
        padding: 1.2rem;
        font-size: 0.9rem;
    }
    
    .course-content p {
        padding: 1.2rem;
        font-size: 0.85rem;
    }
    
    .certificates-grid {
        grid-template-columns: 1fr;
    }
    
    .interest-tags {
        justify-content: center;
    }
    
    .tag {
        font-size: 0.9rem;
        padding: 0.6rem 1.2rem;
    }
    
    section {
        margin-bottom: 3rem;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .project-card {
        padding: 1.5rem;
    }
    
    .quote-text {
        font-size: 1.8rem;
    }
    
    .quote-author {
        font-size: 1rem;
    }
    
    .quote-section {
        padding: 4rem 1.5rem;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .skill-card {
        padding: 1.5rem;
    }
    
    .personal-skill-badge {
        padding: 1.2rem 1.5rem;
        max-width: 100%;
    }
    
    .badge-content h4 {
        font-size: 1rem;
    }
    
    .badge-content p {
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .video-btn {
        padding: 0.6rem 1.2rem;
        font-size: 0.9rem;
    }
    
    .about p {
        padding: 1.5rem;
    }
    
    .certificate-container {
        padding: 1rem;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .quote-text {
        font-size: 1.5rem;
    }
    
    .quote-section {
        padding: 3rem 1rem;
    }
}