:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --text-primary: #1a1a2e;
    --text-secondary: #495057;
    --text-muted: #6c757d;
    --accent: #2563eb;
    --accent-dark: #1d4ed8;
    --accent-light: #3b82f6;
    --border: #dee2e6;
    --border-dark: #ced4da;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --transition: all 0.2s ease;
}

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

html {
    scroll-behavior: smooth;
}

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

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: 48px 0;
    border-bottom: 1px solid var(--border);
}

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

.section-header {
    margin-bottom: 32px;
}

.section-title {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 40px;
    height: 3px;
    background: var(--accent);
    border-radius: 2px;
}

.header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    padding: 48px 0;
}

.header-container {
    display: flex;
    justify-content: center;
}

.profile-section {
    display: flex;
    align-items: center;
    gap: 32px;
    max-width: 100%;
}

.profile-image {
    flex-shrink: 0;
}

.profile-image img {
    width: 180px;
    height: 180px;
    object-fit: cover;
    border-radius: 50%;
    border: 4px solid var(--bg-primary);
    box-shadow: var(--shadow-md);
}

.profile-info {
    flex: 1;
}

.profile-name {
    font-size: 32px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.profile-title {
    font-size: 16px;
    color: var(--accent);
    font-weight: 500;
    margin-bottom: 16px;
}

.profile-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 20px;
}

.meta-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    color: var(--text-secondary);
}

.meta-item svg {
    color: var(--text-muted);
}

.profile-links {
    display: flex;
    gap: 12px;
}

.profile-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 13px;
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
}

.profile-link:hover {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
}

.nav {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 8px;
    padding: 12px 0;
    overflow-x: auto;
}

.nav-menu a {
    display: block;
    padding: 8px 16px;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    white-space: nowrap;
}

.nav-menu a:hover {
    background: var(--bg-primary);
    color: var(--accent);
}

.about-content {
    max-width: 800px;
}

.about-content p {
    font-size: 15px;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.7;
}

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

.about-content strong {
    color: var(--text-primary);
    font-weight: 600;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.skill-item {
    padding: 20px;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
}

.skill-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.skill-desc {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.5;
}

.timeline {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.timeline-item {
    padding: 24px;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
}

.timeline-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 16px;
    gap: 16px;
}

.company-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
}

.job-title {
    font-size: 14px;
    color: var(--accent);
    font-weight: 500;
    margin-top: 4px;
}

.period {
    font-size: 13px;
    color: var(--text-muted);
    font-weight: 500;
    white-space: nowrap;
    padding: 4px 12px;
    background: var(--bg-tertiary);
    border-radius: 20px;
}

.job-details {
    list-style: none;
    margin-bottom: 16px;
}

.job-details li {
    font-size: 14px;
    color: var(--text-secondary);
    padding: 6px 0 6px 16px;
    position: relative;
    line-height: 1.6;
}

.job-details li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--accent);
}

.tech-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tech-tags span {
    font-size: 12px;
    padding: 4px 10px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 4px;
    color: var(--text-muted);
}

.education-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.education-item {
    padding: 20px;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
}

.education-degree {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--accent);
    display: block;
    margin-bottom: 8px;
}

.education-course {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
}

.contact-intro {
    font-size: 15px;
    color: var(--text-secondary);
    margin-bottom: 24px;
    line-height: 1.6;
}

.contact-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.contact-item {
    display: flex;
    flex-direction: column;
    padding: 16px;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    text-decoration: none;
    transition: var(--transition);
}

.contact-item:hover {
    border-color: var(--accent);
    box-shadow: var(--shadow-sm);
}

.contact-label {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.contact-value {
    font-size: 14px;
    color: var(--text-primary);
    font-weight: 500;
}

.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 24px 0;
    text-align: center;
}

.footer p {
    font-size: 13px;
    color: var(--text-muted);
}

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

    .profile-image img {
        width: 150px;
        height: 150px;
    }

    .profile-meta {
        justify-content: center;
    }

    .profile-links {
        justify-content: center;
    }

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

    .education-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

@media (max-width: 480px) {
    .profile-name {
        font-size: 24px;
    }

    .profile-meta {
        flex-direction: column;
        gap: 8px;
    }

    .timeline-header {
        flex-direction: column;
    }

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