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

:root {
    --primary-color: #2563eb;
    --accent-color: #0ea5e9;
    --bg-main: #f5f5f7;
    --bg-white: #ffffff;
    --bg-sidebar: #fafafa;
    --text-primary: #1d1d1f;
    --text-secondary: #6e6e73;
    --border-color: #d2d2d7;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-hover: 0 4px 16px rgba(0, 0, 0, 0.12);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-main);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    padding: 3rem;
}

.container {
    display: flex;
    height: calc(100vh - 6rem);
    max-width: 1400px;
    margin: 0 auto;
    background: var(--bg-white);
    box-shadow: 0 0 40px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.sidebar {
    width: 350px;
    background: var(--bg-white);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    height: 100%;
    overflow-y: auto;
    transition: transform 0.3s ease;
    z-index: 1000;
}

.sidebar::-webkit-scrollbar {
    width: 6px;
}

.sidebar::-webkit-scrollbar-track {
    background: transparent;
}

.sidebar::-webkit-scrollbar-thumb {
    background: #d2d2d7;
    border-radius: 3px;
}

.sidebar-content {
    padding: 3rem 2rem;
}

.profile-section {
    text-align: center;
    margin-bottom: 2.5rem;
    padding-bottom: 2.5rem;
    border-bottom: 1px solid var(--border-color);
}

.profile-image-wrapper {
    width: 140px;
    height: 140px;
    margin: 0 auto 1.5rem;
    position: relative;
}

.profile-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border: 3px solid var(--border-color);
}

.profile-name {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.profile-title {
    font-size: 0.95rem;
    color: var(--text-secondary);
    font-weight: 400;
    line-height: 1.4;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.social-link {
    width: 36px;
    height: 36px;
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.2s ease;
    font-size: 1rem;
}

.social-link:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.navigation {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.25rem;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.2s ease;
    font-weight: 500;
    position: relative;
}

.nav-link::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 3px;
    background: var(--primary-color);
    transform: scaleY(0);
    transition: transform 0.2s ease;
}

.nav-link:hover,
.nav-link.active {
    background: var(--bg-main);
    color: var(--primary-color);
}

.nav-link.active::before {
    transform: scaleY(1);
}

.nav-link i {
    font-size: 1.1rem;
    width: 20px;
}

.sidebar-footer {
    margin-top: auto;
    padding-top: 2rem;
    text-align: center;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.menu-toggle {
    display: none;
    position: fixed;
    top: 1.5rem;
    right: 1.5rem;
    width: 48px;
    height: 48px;
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    font-size: 1.2rem;
    cursor: pointer;
    z-index: 1001;
    transition: all 0.2s ease;
}

.menu-toggle:hover {
    background: var(--bg-main);
}

.main-content {
    flex: 1;
    padding: 4rem 3rem;
    height: 100%;
    overflow-y: auto;
}

.section {
    display: none;
    animation: fadeIn 0.4s ease;
}

.section.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section-content {
    max-width: 900px;
}

.section-header {
    margin-bottom: 3rem;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.title-line {
    height: 1px;
    background: var(--border-color);
    margin-top: 1.5rem;
}

.about-grid {
    display: grid;
    gap: 2.5rem;
}

.about-text p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-size: 1rem;
    line-height: 1.7;
}

.lead-text {
    font-size: 1.15rem !important;
    font-weight: 500;
    color: var(--text-primary) !important;
}

.info-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.25rem;
    margin-top: 2rem;
}

.info-card {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    transition: all 0.2s ease;
}

.info-card:hover {
    box-shadow: var(--shadow-hover);
}

.info-card i {
    font-size: 1.4rem;
    color: var(--primary-color);
    margin-top: 0.25rem;
}

.info-card h3 {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.info-card p {
    color: var(--text-primary);
    font-size: 0.95rem;
    line-height: 1.5;
}

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

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

.timeline-item {
    position: relative;
    margin-bottom: 2.5rem;
    padding-left: 2rem;
}

.timeline-marker {
    position: absolute;
    left: -2rem;
    top: 8px;
    width: 12px;
    height: 12px;
    background: var(--primary-color);
    border: 3px solid var(--bg-main);
    z-index: 1;
}

.timeline-content {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    padding: 2rem;
    transition: all 0.2s ease;
}

.timeline-content:hover {
    box-shadow: var(--shadow-hover);
}

.timeline-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 0.75rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.timeline-header h3 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary);
}

.timeline-date {
    font-size: 0.875rem;
    color: var(--primary-color);
    font-weight: 600;
    white-space: nowrap;
}

.company {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
    font-weight: 500;
}

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

.timeline-list li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.timeline-list li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

.education-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.education-card {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    padding: 2rem;
    display: flex;
    gap: 1.5rem;
    transition: all 0.2s ease;
}

.education-card:hover {
    box-shadow: var(--shadow-hover);
}

.education-icon {
    width: 56px;
    height: 56px;
    background: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.education-icon i {
    font-size: 1.6rem;
    color: white;
}

.education-content h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.education-content h4 {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-weight: 500;
}

.education-status {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: #dbeafe;
    color: var(--primary-color);
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.education-status.completed {
    background: #dcfce7;
    color: #16a34a;
}

.education-date {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.skills-grid {
    display: grid;
    gap: 1.5rem;
}

.skill-category {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    padding: 2rem;
    transition: all 0.2s ease;
}

.skill-category:hover {
    box-shadow: var(--shadow-hover);
}

.skill-category h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.skill-category h3 i {
    color: var(--primary-color);
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.625rem;
}

.skill-tag {
    padding: 0.5rem 1rem;
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    font-size: 0.875rem;
    font-weight: 500;
    transition: all 0.2s ease;
    cursor: default;
}

.skill-tag:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.projects-grid {
    display: grid;
    gap: 1.5rem;
}

.project-card {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    padding: 2rem;
    transition: all 0.2s ease;
}

.project-card:hover {
    box-shadow: var(--shadow-hover);
}

.project-header {
    margin-bottom: 1.25rem;
}

.project-header h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    padding: 0.325rem 0.75rem;
    background: var(--bg-main);
    border: 1px solid var(--border-color);
    color: var(--primary-color);
    font-size: 0.8rem;
    font-weight: 600;
}

.project-card p {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 0.975rem;
    margin-bottom: 1.25rem;
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    background: var(--primary-color);
    color: white;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 600;
    transition: all 0.2s ease;
    margin-top: 0.5rem;
}

.project-link:hover {
    background: var(--accent-color);
    transform: translateX(3px);
}

.project-link i {
    font-size: 0.875rem;
}

.contact-content {
    display: grid;
    gap: 2.5rem;
}

.contact-text {
    max-width: 700px;
}

.contact-text p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-size: 1rem;
    line-height: 1.7;
}

.contact-methods {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.25rem;
}

.contact-card {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    padding: 1.75rem 1.5rem;
    text-align: center;
    text-decoration: none;
    color: inherit;
    transition: all 0.2s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.875rem;
}

.contact-card:hover {
    box-shadow: var(--shadow-hover);
}

.contact-card i {
    font-size: 1.75rem;
    color: var(--primary-color);
}

.contact-card h3 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

.contact-card p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin: 0;
    word-break: break-word;
}

@media (max-width: 968px) {
    body {
        padding: 0;
    }

    .container {
        height: 100vh;
        max-width: 100%;
        flex-direction: column;
        box-shadow: none;
    }

    .sidebar {
        width: 280px;
        max-width: 85%;
        border-right: none;
        position: fixed;
        top: 0;
        left: 0;
        height: 100vh;
        background: var(--bg-white);
        transform: translateX(-100%);
        z-index: 1001;
        box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
    }

    .sidebar.active {
        transform: translateX(0);
    }

    .menu-toggle {
        display: flex;
        align-items: center;
        justify-content: center;
        position: fixed;
        top: 1rem;
        right: 1rem;
    }

    .main-content {
        padding: 4.5rem 1.5rem 2rem;
        height: 100%;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .info-cards {
        grid-template-columns: 1fr;
    }

    .timeline {
        padding-left: 1.5rem;
    }

    .timeline-item {
        padding-left: 1.5rem;
    }

    .timeline-marker {
        left: -1.5rem;
    }

    .timeline-header {
        flex-direction: column;
        align-items: flex-start;
    }

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

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

    .about-text p {
        font-size: 0.95rem;
    }

    .lead-text {
        font-size: 1.05rem !important;
    }
}

@media (max-width: 640px) {
    .section-title {
        font-size: 1.5rem;
    }

    .main-content {
        padding: 4.5rem 1.25rem 1.5rem;
    }

    .timeline-content,
    .project-card,
    .skill-category,
    .education-card {
        padding: 1.25rem;
    }

    .profile-name {
        font-size: 1.5rem;
    }

    .profile-title {
        font-size: 0.875rem;
    }

    .sidebar-content {
        padding: 2rem 1.5rem;
    }

    .info-card {
        padding: 1.25rem;
    }

    .education-icon {
        width: 48px;
        height: 48px;
    }

    .education-icon i {
        font-size: 1.4rem;
    }

    .timeline-header h3 {
        font-size: 1.1rem;
    }

    .project-header h3 {
        font-size: 1.15rem;
    }

    .skill-category h3 {
        font-size: 1rem;
    }

    .about-text p,
    .contact-text p,
    .project-card p {
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .menu-toggle {
        width: 44px;
        height: 44px;
        top: 0.75rem;
        right: 0.75rem;
    }

    .main-content {
        padding: 4rem 1rem 1.25rem;
    }

    .section-title {
        font-size: 1.375rem;
    }

    .profile-image-wrapper {
        width: 120px;
        height: 120px;
    }

    .social-links {
        gap: 0.5rem;
    }

    .social-link {
        width: 32px;
        height: 32px;
        font-size: 0.9rem;
    }

    .skill-tags,
    .project-tags {
        gap: 0.5rem;
    }

    .skill-tag,
    .tag {
        font-size: 0.8rem;
        padding: 0.375rem 0.75rem;
    }

    .timeline-content,
    .project-card,
    .skill-category,
    .education-card,
    .info-card {
        padding: 1rem;
    }

    .contact-card {
        padding: 1.25rem 1rem;
    }

    .education-card {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .education-icon {
        width: 56px;
        height: 56px;
    }
}