/* Base styles */
:root {
    --color-primary: #0050b3;
    --color-primary-light: #1890ff;
    --color-primary-dark: #003a8c;
    --color-text: #333333;
    --color-text-secondary: #666666;
    --color-background: #ffffff;
    --color-background-alt: #f8f9fa;
    --color-border: #e8e8e8;
    --color-success: #52c41a;
    --color-warning: #faad14;
    --color-danger: #f5222d;
    --font-main: 'Roboto', sans-serif;
    --font-code: 'Roboto Mono', monospace;
    --transition-speed: 0.3s;
    --shadow-small: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-medium: 0 4px 12px rgba(0, 0, 0, 0.12);
    --border-radius: 4px;
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-xxl: 3rem;
}

/* Reset and base styles */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-main);
    color: var(--color-text);
    line-height: 1.6;
    background-color: var(--color-background);
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 500;
    line-height: 1.3;
    margin-bottom: var(--spacing-md);
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    word-wrap: break-word;
    hyphens: auto;
}

h2 {
    font-size: 2rem;
    color: var(--color-primary-dark);
    position: relative;
    padding-bottom: var(--spacing-sm);
}

h2.section-title::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    height: 3px;
    width: 60px;
    background-color: var(--color-primary);
}

h3 {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
}

h4 {
    font-size: 1.25rem;
    font-weight: 500;
    margin-bottom: var(--spacing-xs);
}

p {
    margin-bottom: var(--spacing-md);
}

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition-speed);
}

a:hover {
    color: var(--color-primary-light);
    text-decoration: underline;
}

ul,
ol {
    padding-left: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

li {
    margin-bottom: var(--spacing-xs);
}

/* Layout */
.site-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.section {
    padding: var(--spacing-xxl) 0;
}

.section:nth-child(even) {
    background-color: var(--color-background-alt);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 500;
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-speed);
    text-decoration: none;
    border: none;
    font-family: var(--font-main);
}

.btn:hover {
    text-decoration: none;
}

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

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

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

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

.btn-pdf {
    background-color: var(--color-danger);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    font-size: 0.9rem;
}

.btn-pdf:hover {
    background-color: #d9363e;
}

/* Navigation */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: var(--color-background);
    box-shadow: var(--shadow-small);
    transition: background-color var(--transition-speed), box-shadow var(--transition-speed);
}

.main-nav.scrolled {
    background-color: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow-medium);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem var(--spacing-lg);
    max-width: 1200px;
    margin: 0 auto;
}

.logo a {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition-speed);
}

.logo a:hover {
    color: var(--color-primary-light);
}

.nav-links {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    align-items: center;
}

.nav-links li {
    margin: 0 0.75rem;
}

.nav-item {
    padding: 0.5rem 0.75rem;
    color: var(--color-text);
    font-weight: 500;
    position: relative;
}

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

.nav-item.active {
    color: var(--color-primary);
}

.nav-item.active::after {
    content: '';
    position: absolute;
    left: 0.75rem;
    right: 0.75rem;
    bottom: 0;
    height: 2px;
    background-color: var(--color-primary);
}

.hamburger {
    display: none;
    cursor: pointer;
    width: 30px;
    height: 20px;
    flex-direction: column;
    justify-content: space-between;
}

.hamburger span {
    height: 2px;
    background-color: var(--color-text);
    width: 100%;
    transition: transform var(--transition-speed), opacity var(--transition-speed);
}

/* Hero section */
.section-hero {
    padding-top: 7rem;
    padding-bottom: var(--spacing-xxl);
    background-color: var(--color-background-alt);
    position: relative;
}

.hero-content {
    display: flex;
    flex-direction: row;
    align-items: center;
    max-width: 900px;
    margin: 0 auto;
    gap: var(--spacing-xl);
}

.hero-photo {
    flex-shrink: 0;
}

.profile-image {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid white;
    box-shadow: var(--shadow-small);
}

.hero-text {
    margin-bottom: var(--spacing-xl);
}

.hero-text h1 {
    margin-bottom: 0.25rem;
    font-size: 2.0rem;
    max-width: 100%;
    overflow-wrap: break-word;
    line-height: 1.2;
}

.hero-text h2 {
    font-size: 1.5rem;
    font-weight: 500;
    padding-bottom: 0;
    margin-bottom: var(--spacing-sm);
    color: var(--color-primary);
}

.hero-text h2::after {
    display: none;
}

.subtitle {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.hero-tech-stack {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: var(--spacing-md);
}

.tech-badge {
    background-color: rgba(24, 144, 255, 0.1);
    color: var(--color-primary);
    padding: 0.25rem 0.75rem;
    border-radius: 100px;
    font-size: 0.875rem;
    font-family: var(--font-code);
    border: 1px solid rgba(24, 144, 255, 0.2);
}

/* About section */
.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--spacing-xl);
}

.about-highlights {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
}

.highlight-box {
    background-color: white;
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-small);
    text-align: center;
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.highlight-box:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-medium);
}

.highlight-box i {
    font-size: 2rem;
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
}

.highlight-box h4 {
    font-weight: 700;
    margin-bottom: 0.25rem;
}

/* Experience section */
.timeline {
    position: relative;
    padding-left: 2rem;
}

.timeline::before {
    content: "";
    position: absolute;
    top: 0;
    bottom: 0;
    left: 7px;
    width: 2px;
    background-color: var(--color-primary-light);
}

.timeline-item {
    position: relative;
    margin-bottom: var(--spacing-xl);
}

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

.timeline-dot {
    position: absolute;
    top: 6px;
    left: -2rem;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background-color: var(--color-primary);
    border: 3px solid white;
    box-shadow: 0 0 0 2px var(--color-primary-light);
}

.timeline-date {
    font-size: 0.875rem;
    margin-bottom: var(--spacing-xs);
    color: var(--color-text-secondary);
    display: flex;
    justify-content: space-between;
}

.timeline-content {
    background-color: white;
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-small);
}

.timeline-content h3 {
    margin-bottom: 0.25rem;
    color: var(--color-primary-dark);
}

.timeline-content h4 {
    font-weight: 400;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-md);
}

.experience-details h5 {
    font-size: 1rem;
    font-weight: 500;
    color: var(--color-primary);
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-xs);
}

/* Skills section */
.skills-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.skills-category {
    margin-bottom: var(--spacing-md);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: var(--spacing-md);
}

.skill-item {
    display: flex;
    background-color: white;
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-small);
}

.skill-icon {
    width: 50px;
    height: 50px;
    background-color: rgba(24, 144, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: var(--spacing-md);
    font-size: 1.5rem;
    color: var(--color-primary);
}

.skill-info {
    flex-grow: 1;
}

.skill-info h4 {
    margin-bottom: 0.25rem;
}

.skill-level {
    display: flex;
    flex-direction: column;
    margin-bottom: var(--spacing-xs);
}

.skill-level span {
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    margin-bottom: 0.25rem;
}

.skill-bar {
    height: 4px;
    width: 100%;
    background-color: var(--color-border);
    border-radius: 2px;
    overflow: hidden;
}

.skill-bar div {
    height: 100%;
    background-color: var(--color-primary);
}

.expert .skill-bar div {
    background-color: #52c41a;
}

.advanced .skill-bar div {
    background-color: #1890ff;
}

.intermediate .skill-bar div {
    background-color: #faad14;
}

.skill-info p {
    font-size: 0.875rem;
    margin: 0.25rem 0 0;
    color: var(--color-text-secondary);
}

.skills-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: var(--spacing-sm);
}

.skill-tag {
    background-color: white;
    padding: 0.5rem 1rem;
    border-radius: 100px;
    font-size: 0.875rem;
    box-shadow: var(--shadow-small);
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.tools-column h4 {
    font-size: 1rem;
    color: var(--color-primary-dark);
    margin-bottom: var(--spacing-xs);
    border-bottom: 1px solid var(--color-border);
    padding-bottom: 0.25rem;
}

.tools-column ul {
    list-style-type: none;
    padding-left: 0;
    margin-bottom: var(--spacing-md);
}

.tools-column li {
    margin-bottom: 0.25rem;
    font-size: 0.9rem;
}

/* Tools section - highlighted elements */
.tools-column ul li.highlight {
    font-weight: 500;
    color: var(--color-primary-dark);
    position: relative;
    padding-left: 5px;
}

.tools-column ul li.highlight::before {
    content: '★';
    position: absolute;
    left: -15px;
    color: var(--color-primary);
}

/* Projects section */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: var (--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.project-card {
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-small);
    padding: var(--spacing-lg);
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-medium);
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--spacing-xs);
}

.project-title {
    margin: 0;
    font-size: 1.5rem;
}

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

.project-link {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
    transition: color var(--transition-speed);
}

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

.project-subtitle {
    font-size: 1.1rem;
    color: var(--color-primary);
    margin-bottom: 0.5rem;
}

.project-description {
    font-size: 0.95rem;
    margin-bottom: var(--spacing-sm);
}

.project-features ul {
    padding-left: var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
}

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: var(--spacing-sm);
}

.tech-tag {
    background-color: rgba(24, 144, 255, 0.1);
    color: var(--color-primary);
    padding: 0.25rem 0.75rem;
    border-radius: 100px;
    font-size: 0.75rem;
    font-family: var(--font-code);
}

.github-cta {
    text-align: center;
    margin-top: var(--spacing-xl);
}

/* Education section */
.education-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: var(--spacing-lg);
}

.education-card {
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-small);
    padding: var(--spacing-lg);
    display: flex;
    align-items: flex-start;
}

.education-icon {
    width: 50px;
    height: 50px;
    background-color: rgba(24, 144, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: var(--spacing-md);
    font-size: 1.5rem;
    color: var(--color-primary);
    flex-shrink: 0;
}

.education-content {
    flex-grow: 1;
}

.education-content h3 {
    margin-bottom: var(--spacing-xs);
}

.education-content h4 {
    color: var(--color-text-secondary);
    font-weight: 400;
    font-size: 1.1rem;
    margin-bottom: var(--spacing-sm);
}

.education-period {
    display: inline-block;
    font-size: 0.8rem;
    color: var(--color-text-secondary);
    margin-top: var(--spacing-xs);
}

.qualification {
    margin-bottom: var(--spacing-sm);
}

.qualification p {
    margin-bottom: 0.25rem;
}

.diploma-honor {
    font-size: 0.8rem;
    background-color: rgba(245, 34, 45, 0.1);
    color: var (--color-danger);
    padding: 0.1rem 0.5rem;
    border-radius: 100px;
    font-weight: 500;
}

.courses-list {
    padding-left: 1rem;
    margin-top: var(--spacing-xs);
}

.courses-list li {
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

/* Contact section */
.contacts-container {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--spacing-lg);
}

.preferred-contact {
    background-color: white;
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-small);
    grid-row: span 2;
}

.contact-item {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.contact-item:last-child {
    margin-bottom: 0;
}

.contact-icon {
    width: 40px;
    height: 40px;
    background-color: rgba(24, 144, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: var(--spacing-md);
    font-size: 1.2rem;
    color: var(--color-primary);
}

.telegram .contact-icon {
    color: #0088cc;
    background-color: rgba(0, 136, 204, 0.1);
}

.contact-info h4 {
    margin-bottom: 0.25rem;
    font-size: 1rem;
}

.other-contacts {
    background-color: white;
    padding: var (--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-small);
}

.contact-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

/* Footer */
.footer {
    background-color: var(--color-background-alt);
    padding: var(--spacing-lg) 0;
    margin-top: auto;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

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

.social-links {
    display: flex;
    gap: var(--spacing-md);
}

.social-links a {
    font-size: 1.5rem;
    color: var(--color-text-secondary);
    transition: color var(--transition-speed);
}

.social-links a:hover {
    color: var(--color-primary);
}

/* Language switcher styles */
.language-toggle {
    margin-left: var(--spacing-md);
}

.language-selector {
    display: flex;
    border-radius: var(--border-radius);
    overflow: hidden;
    border: 1px solid var(--color-border);
}

.language-btn {
    background: none;
    border: none;
    padding: 0.25rem 0.5rem;
    font-family: var(--font-main);
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-speed);
    color: var(--color-text-secondary);
}

.language-btn:hover {
    color: var(--color-primary);
}

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

/* Responsive styles */
@media (max-width: 992px) {
    html {
        font-size: 15px;
    }

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

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

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

    .contacts-container {
        grid-template-columns: 1fr;
    }

    .preferred-contact {
        grid-row: auto;
    }
}

@media (max-width: 768px) {
    html {
        font-size: 14px;
    }

    h1 {
        font-size: 1.8rem;
    }

    .nav-container {
        padding: 0.75rem var(--spacing-md);
    }

    .nav-links {
        position: fixed;
        top: 60px;
        left: 0;
        width: 100%;
        background-color: var(--color-background);
        box-shadow: var(--shadow-small);
        flex-direction: column;
        align-items: center;
        padding: var(--spacing-md) 0;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: transform var(--transition-speed), opacity var (--transition-speed), visibility var(--transition-speed);
    }

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

    .nav-links li {
        width: 100%;
        text-align: center;
        margin: 0.25rem 0;
    }

    .nav-item {
        display: block;
        padding: 0.75rem;
    }

    .nav-item.active::after {
        display: none;
    }

    .hamburger {
        display: flex;
    }

    .hamburger.active span:nth-child(1) {
        transform: translateY(9px) rotate(45deg);
    }

    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
        transform: translateY(-9px) rotate(-45deg);
    }

    .hero-cta {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .about-highlights {
        grid-template-columns: 1fr;
    }

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

    .hero-content {
        flex-direction: column;
        text-align: center;
        align-items: center;
    }

    .hero-text {
        margin-top: var(--spacing-md);
    }

    .language-toggle {
        margin: 0.5rem 0;
    }

    .language-selector {
        justify-content: center;
        width: 120px;
        margin: 0 auto;
    }

    .language-btn {
        flex: 1;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .section {
        padding: var(--spacing-xl) 0;
    }

    .container {
        padding: 0 var(--spacing-md);
    }

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

    .hero-text h1 {
        font-size: 1.7rem;
    }
}

/* Print styles */
@media print {
    @page {
        size: A4;
        margin: 1cm;
    }

    body {
        font-size: 12pt;
        color: #000;
        background: #fff;
    }

    .main-nav,
    .hamburger,
    .btn-pdf,
    #download-pdf-btn,
    .hero-cta,
    .social-links,
    .footer {
        display: none !important;
    }

    a {
        color: #000;
        text-decoration: none;
    }

    h1,
    h2,
    h3,
    h4,
    h5,
    h6 {
        page-break-after: avoid;
        page-break-inside: avoid;
    }

    .section {
        padding: 20pt 0;
        page-break-inside: avoid;
    }

    .section-hero {
        padding-top: 0;
    }

    .profile-image {
        max-width: 100px !important;
        height: auto !important;
        border: 1px solid #ddd;
        box-shadow: none !important;
    }

    .project-links {
        display: none;
    }

    .skill-icon,
    .contact-icon,
    .education-icon,
    .highlight-box,
    .project-card,
    .timeline-content,
    .skill-item,
    .education-card,
    .contact-item {
        box-shadow: none !important;
        border: 1px solid #ddd;
    }

    .section-title::after {
        background-color: #000;
    }
}