:root {
    --bg-primary: #0d0d0d;
    --bg-secondary: #161616;
    --bg-tertiary: #1f1f1f;
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --text-muted: #666666;
    --accent-primary: #3b82f6;
    --accent-secondary: #8b5cf6;
    --accent-gradient: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
    --border-color: #2a2a2a;
    --card-bg: #1a1a1a;
    --nav-height: 70px;
    --container-max: 1100px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

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

.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 2rem;
}

.section {
    padding: 6rem 0;
}

.section-alt {
    background-color: var(--bg-secondary);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 3rem;
    text-align: center;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--accent-gradient);
    margin: 1rem auto 0;
    border-radius: 2px;
}

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background: transparent;
    backdrop-filter: none;
    z-index: 1000;
    border-bottom: 1px solid transparent;
    box-shadow: none;
    transition: background 0.4s ease, border-bottom 0.4s ease, box-shadow 0.4s ease, backdrop-filter 0.4s ease;
}

.navbar.scrolled {
    background: rgba(13, 13, 13, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
}

.nav-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 2rem;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 1.1rem;
}

.nav-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--accent-primary);
}

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

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: var(--transition);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-gradient);
    transition: var(--transition);
}

.nav-link:hover {
    color: var(--text-primary);
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.nav-toggle span {
    width: 25px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 2rem;
    padding-top: var(--nav-height);
    position: relative;
    background: radial-gradient(ellipse at top, rgba(59, 130, 246, 0.1) 0%, transparent 50%);
}

.hero-content {
    max-width: 700px;
}

.hero-image {
    margin-bottom: 2rem;
}

.hero-image img {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--accent-primary);
    box-shadow: 0 0 40px rgba(59, 130, 246, 0.3);
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    line-height: 1.2;
}

.highlight {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--accent-primary);
    font-weight: 500;
    margin-bottom: 1rem;
}

.hero-tagline {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1rem;
    transition: var(--transition);
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    border: none;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(59, 130, 246, 0.4);
}

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

.btn-secondary:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.hero-scroll {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
}

.hero-scroll a {
    color: var(--text-muted);
    transition: var(--transition);
}

.hero-scroll a:hover {
    color: var(--accent-primary);
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-content p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.about-content p:last-child {
    margin-bottom: 0;
}

.timeline {
    max-width: 700px;
    margin: 0 auto;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border-color);
}

.timeline-item {
    position: relative;
    padding-left: 2rem;
    padding-bottom: 3rem;
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.timeline-marker {
    position: absolute;
    left: -5px;
    top: 5px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--accent-primary);
    box-shadow: 0 0 10px rgba(59, 130, 246, 0.5);
}

.timeline-content {
    background: var(--card-bg);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.timeline-content:hover {
    border-color: var(--accent-primary);
    transform: translateX(5px);
}

.timeline-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.timeline-company {
    color: var(--accent-primary);
    font-weight: 500;
    margin-bottom: 0.75rem;
}

.timeline-date {
    color: var(--text-muted);
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 0.75rem;
}

.timeline-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.timeline-description:empty {
    display: none;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1.5rem;
    max-width: 900px;
    margin: 0 auto 3rem;
}

.skill-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem 1.5rem;
    text-align: center;
    transition: var(--transition);
}

.skill-card:hover {
    border-color: var(--accent-primary);
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.skill-icon {
    color: var(--accent-primary);
    margin-bottom: 1rem;
    display: flex;
    justify-content: center;
}

.skill-name {
    font-size: 1rem;
    font-weight: 600;
}

.certifications {
    text-align: center;
    margin-top: 3rem;
}

.certifications-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
}

.certifications-list {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.certification-badge {
    background: var(--card-bg);
    border: 1px solid var(--accent-primary);
    color: var(--accent-primary);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 500;
}

.certifications-subtitle {
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-muted);
    margin-top: 2rem;
    margin-bottom: 1rem;
}

.certification-badge-expired {
    background: var(--card-bg);
    border: 1px solid var(--text-muted);
    color: var(--text-secondary);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 500;
}

.education-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.education-item {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    transition: var(--transition);
}

.education-item:hover {
    border-color: var(--accent-primary);
    transform: translateY(-3px);
}

.education-degree {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.education-school {
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}

.education-date {
    color: var(--text-muted);
    font-size: 0.85rem;
    font-weight: 500;
}

.contact-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.contact-intro {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

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

.contact-link {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 1rem 2rem;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: var(--transition);
}

.contact-link:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    transform: translateY(-2px);
}

.contact-link svg {
    flex-shrink: 0;
}

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

.footer p {
    color: var(--text-muted);
    font-size: 0.875rem;
}

@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--bg-primary);
        flex-direction: column;
        padding: 2rem;
        gap: 1.5rem;
        border-bottom: 1px solid var(--border-color);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.25rem;
    }

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

    .section {
        padding: 4rem 0;
    }

    .timeline::before {
        left: 5px;
    }

    .timeline-item {
        padding-left: 2rem;
    }

    .timeline-marker {
        left: 0;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-content > * {
    animation: fadeInUp 0.6s ease forwards;
}

.hero-content > *:nth-child(1) { animation-delay: 0.1s; }
.hero-content > *:nth-child(2) { animation-delay: 0.2s; }
.hero-content > *:nth-child(3) { animation-delay: 0.3s; }
.hero-content > *:nth-child(4) { animation-delay: 0.4s; }
.hero-content > *:nth-child(5) { animation-delay: 0.5s; }