:root {
  color-scheme: dark;
  --background: #101419;
  --surface: #171c23;
  --surface-hover: #1c232d;
  --text: #eef1f5;
  --muted: #a0aab8;
  --accent: #91b8ea;
  --line: #2b333e;
  --content-width: 1160px;
  --header-height: 84px;
  --radius: 22px;
  --glass-fill: rgba(12, 16, 22, .72);
  --glass-border: rgba(225, 234, 245, .07);
  --glass-shadow: inset 0 1px 0 rgba(255, 255, 255, .025);
}

*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-height) + 24px); }
body {
  background: var(--background);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
#vanta-background, #particle-canvas {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}
#vanta-background { opacity: .58; }
#particle-canvas { opacity: .45; }
body::after {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background: linear-gradient(to bottom, rgba(0, 0, 0, .2), #000 88%);
}
.page, .site-footer { position: relative; z-index: 1; }
a { color: inherit; text-decoration: none; }
button { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a:focus-visible, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 5px; }
::selection { background: #365780; color: #fff; }
.skip-link { position: fixed; top: -100px; left: 24px; z-index: 100; padding: 12px 20px; color: var(--background); background: var(--text); }
.skip-link:focus { top: 12px; }
.scroll-progress { position: fixed; top: 0; left: 0; z-index: 60; width: 100%; height: 2px; background: var(--accent); transform: scaleX(0); transform-origin: left; }
.site-nav, .section-inner, .hero-inner, .footer-inner { width: min(100%, var(--content-width)); margin-inline: auto; }
.site-header { position: sticky; top: 0; z-index: 50; padding-inline: 32px; border-bottom: 1px solid var(--line); background: rgba(16, 20, 25, .96); }
.site-nav { min-height: var(--header-height); display: flex; justify-content: space-between; align-items: center; gap: 24px; }
.brand { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
.brand-mark { width: 40px; height: 40px; display: grid; place-items: center; border: 1px solid #52647a; border-radius: 4px; color: var(--accent); font-size: 13px; font-weight: 700; letter-spacing: -.03em; }
.brand-text { display: flex; flex-direction: column; gap: 2px; font-size: 13px; font-weight: 600; line-height: 1.5; }
.brand-role { color: var(--muted); font-size: 11px; font-weight: 400; }
.nav-links { display: flex; align-items: center; gap: 22px; }
.nav-link { position: relative; padding-block: 8px; font-size: 12px; color: var(--muted); transition: color 180ms; }
.nav-link:hover, .nav-link.is-active { color: var(--text); }
.nav-link.is-active::after { content: ''; position: absolute; height: 2px; background: var(--accent); bottom: 0; left: 0; right: 0; }
.nav-lang { display: flex; align-items: center; gap: 5px; border-left: 1px solid var(--line); padding-left: 14px; }
.lang-toggle { min-height: 44px; min-width: 30px; border: 0; background: transparent; color: var(--muted); font-size: 11px; cursor: pointer; }
.lang-active { color: var(--accent); font-weight: 700; }
.lang-separator { color: #586372; font-size: 11px; }
.nav-toggle { display: none; }
.section { padding: 88px 32px; }
.section + .section { border-top: 1px solid var(--line); }
.section-alt { background: transparent; }
.hero { padding-block: 104px 112px; }
.hero-inner { display: grid; grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr); align-items: center; gap: 76px; }
.eyebrow { color: var(--muted); font-size: 10px; font-weight: 600; letter-spacing: .14em; line-height: 1.6; text-transform: uppercase; }
.hero-copy > .eyebrow { color: var(--accent); margin-bottom: 24px; }
.hero-name { font-size: clamp(48px, 5.7vw, 78px); line-height: 1.06; font-weight: 600; letter-spacing: -.055em; }
.hero-name-part { display: block; }
.hero-role { margin-top: 24px; font-size: 21px; color: var(--accent); font-weight: 500; letter-spacing: -.02em; }
.hero-text { margin-top: 20px; max-width: 560px; color: var(--muted); font-size: 16px; line-height: 1.85; }
.hero-actions { display: flex; align-items: center; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.btn { min-height: 48px; display: inline-flex; justify-content: center; align-items: center; padding: 12px 22px; border: 1px solid transparent; border-radius: 4px; font-size: 13px; font-weight: 600; transition: background 180ms, border-color 180ms; }
.btn-primary { background: #c4d9f4; color: #131c28; }
.btn-primary:hover { background: #dce9fa; }
.btn-secondary { border-color: #45505e; }
.btn-secondary::after { content: '↗'; margin-left: 16px; color: var(--accent); font-size: 17px; }
.btn-secondary:hover { background: var(--surface); border-color: var(--accent); }
.hero-panel, .card, .timeline-item-current, .icon-button {
  border: 1px solid var(--glass-border);
  background: var(--glass-fill);
  box-shadow: var(--glass-shadow);
  border-radius: var(--radius);
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
}
@supports ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  :root { --glass-fill: linear-gradient(155deg, rgba(255, 255, 255, .025), transparent 65%), rgba(12, 16, 22, .18); }
}
.hero-panel { overflow: hidden; }
.panel-header { display: flex; align-items: center; gap: 10px; padding: 24px 30px; border-bottom: 1px solid rgba(194, 214, 240, .1); font-size: 12px; font-weight: 500; }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent); flex-shrink: 0; }
.signal-list { padding: 4px 30px; }
.signal-item { padding-block: 20px; }
.signal-item + .signal-item { border-top: 1px solid rgba(194, 214, 240, .1); }
.signal-item dt { margin-bottom: 7px; color: var(--muted); font-size: 11px; }
.signal-item dd { font-size: 14px; line-height: 1.7; }
.panel-education { position: relative; display: flex; flex-direction: column; gap: 7px; border-top: 1px solid var(--glass-border); padding: 24px 48px 28px 30px; background: rgba(145, 184, 234, .025); transition: background 180ms; }
.panel-education:hover { background: rgba(145, 184, 234, .055); }
.panel-education-label { color: var(--accent); font-size: 10px; letter-spacing: .06em; text-transform: uppercase; }
.panel-education-title { font-size: 14px; font-weight: 500; }
.panel-arrow { position: absolute; right: 24px; top: 22px; color: var(--accent); }
.section-heading { margin-top: 12px; font-size: clamp(28px, 3vw, 38px); line-height: 1.2; letter-spacing: -.035em; font-weight: 500; }
.section-header { margin-bottom: 36px; }
.split-layout { display: grid; grid-template-columns: 270px minmax(0, 1fr); gap: 64px; }
.lead-text { font-size: 25px; font-weight: 400; line-height: 1.5; letter-spacing: -.02em; max-width: 720px; }
.body-text { margin-top: 20px; color: var(--muted); font-size: 15px; line-height: 1.85; }
.card-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 22px; }
.card { min-width: 0; padding: 32px; }
#skills .card { display: flex; flex-direction: column; }
#skills .card-desc { flex: 1; }
.card-title { font-size: 21px; font-weight: 500; line-height: 1.45; letter-spacing: -.015em; overflow-wrap: anywhere; }
.card-desc, .card-body { margin-top: 14px; color: var(--muted); font-size: 14px; line-height: 1.8; }
.tag-grid { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 24px; }
.tag { border: 1px solid rgba(194, 214, 240, .12); background: rgba(194, 214, 240, .045); border-radius: 7px; padding: 5px 10px; color: #c2cbd7; font-size: 11px; line-height: 1.5; }
.project-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 22px; }
.card-clickable { padding: 0; transition: border-color 220ms; }
.card-clickable:hover { border-color: rgba(225, 234, 245, .16); }
.card-link { height: 100%; display: flex; flex-direction: column; padding: 30px; border-radius: var(--radius); }
.card-link:focus-visible { outline-offset: -3px; }
.card-index { align-self: flex-start; display: grid; place-items: center; width: 36px; height: 36px; margin-bottom: 26px; border-radius: 11px; border: 1px solid rgba(194, 214, 240, .12); background: rgba(145, 184, 234, .07); font-family: ui-monospace, SFMono-Regular, Consolas, monospace; font-size: 11px; color: var(--accent); }
.project-card .card-body { flex: 1; }
.card-stack { border-top: 1px solid rgba(194, 214, 240, .1); margin-top: 24px; padding-top: 16px; color: #aebed3; font-size: 11px; line-height: 1.8; }
.project-source { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-top: 22px; font-size: 12px; font-weight: 500; }
.project-source::after { content: '↗'; color: var(--accent); font-size: 18px; }
.timeline { position: relative; padding-left: 28px; border-left: 1px solid var(--line); }
.timeline-item { position: relative; padding-bottom: 32px; }
.timeline-item:last-child { padding-bottom: 0; }
.timeline-point { position: absolute; top: 7px; left: -33px; width: 9px; height: 9px; border-radius: 50%; background: #687587; border: 2px solid var(--background); }
.timeline-period { color: var(--muted); font-size: 12px; font-weight: 500; }
.timeline-title { margin-top: 10px; max-width: 640px; font-size: 18px; font-weight: 500; line-height: 1.5; }
.timeline-body { margin-top: 10px; color: var(--muted); font-size: 14px; line-height: 1.8; }
.timeline-item-current { padding: 30px; margin-bottom: 32px; border-color: rgba(145, 184, 234, .12); }
.timeline-item-current .timeline-point { top: 38px; left: -34px; background: var(--accent); }
.education-meta { display: flex; align-items: center; flex-wrap: wrap; gap: 12px; }
.timeline-item-current .timeline-period { color: var(--accent); }
.education-status { padding: 4px 10px; background: rgba(145, 184, 234, .08); border: 1px solid rgba(145, 184, 234, .22); border-radius: 20px; color: #c4d9f4; font-size: 10px; line-height: 1.6; }
.education-faculty { margin-top: 8px; color: var(--muted); font-size: 14px; line-height: 1.7; }
.education-program { margin-top: 18px; font-size: 17px; font-weight: 500; color: #c4d9f4; }
.certificate-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.certificate-card { position: relative; overflow: hidden; }
.certificate-card .card-link { padding-top: 158px; }
.certificate-card::before { content: ''; position: absolute; left: 0; right: 0; top: 0; height: 132px; background: var(--certificate-image) center / cover; opacity: .9; mask-image: linear-gradient(#000 60%, transparent); pointer-events: none; }
.certificate-card .card-title { font-size: 16px; }
.certificate-card .card-title::after { content: '↗'; margin-left: 8px; color: var(--accent); font-size: 15px; }
.certificate-card .card-body { margin-top: 10px; font-size: 13px; }
.certificate-card-it { --certificate-image: url('IT.jpg'); }
.certificate-card-oil-gas { --certificate-image: url('oil.jpg'); }
.certificate-card-aviation { --certificate-image: url('aviation.jpg'); }
.certificate-card-ir { --certificate-image: url('IR%20.jpg'); }
.certificate-card-sports { --certificate-image: url('sports.jpg'); }
.certificate-card-education { --certificate-image: url('education.jpg'); }
.section-inner-contact { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 80px; align-items: center; }
.contact-subtitle { margin-top: 22px; color: var(--muted); max-width: 470px; font-size: 15px; line-height: 1.85; }
.contact-links { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; }
.icon-button { display: flex; align-items: center; gap: 12px; padding: 20px; border-radius: 16px; font-size: 13px; transition: background 180ms, border-color 180ms; }
.icon-button::after { content: '↗'; margin-left: auto; color: var(--muted); }
.icon-button:hover { border-color: rgba(225, 234, 245, .16); }
.icon-circle { display: grid; place-items: center; width: 28px; height: 28px; color: var(--accent); font-size: 12px; font-weight: 600; }
.site-footer { padding: 26px 32px; border-top: 1px solid var(--line); }
.footer-inner { display: flex; justify-content: space-between; gap: 16px; color: var(--muted); font-size: 11px; }

@media (max-width: 1100px) {
  .nav-toggle { display: flex; flex-direction: column; justify-content: center; gap: 6px; width: 44px; height: 44px; padding: 10px; border: 1px solid var(--line); background: transparent; border-radius: 4px; cursor: pointer; }
  .nav-toggle span { display: block; width: 22px; height: 1px; background: var(--text); transition: transform 180ms; }
  .nav-toggle.is-open span:first-child { transform: translateY(3.5px) rotate(45deg); }
  .nav-toggle.is-open span:last-child { transform: translateY(-3.5px) rotate(-45deg); }
  .nav-links { display: none; position: absolute; top: 100%; left: 0; right: 0; max-height: calc(100dvh - var(--header-height)); overflow-y: auto; padding: 16px 32px 24px; background: var(--background); border-bottom: 1px solid var(--line); box-shadow: 0 20px 28px #0003; }
  .nav-links.is-open { display: flex; flex-direction: column; align-items: stretch; gap: 0; }
  .nav-link { padding: 12px 0; font-size: 14px; }
  .nav-link.is-active::after { display: none; }
  .nav-lang { margin-top: 12px; padding: 10px 0 0; border-left: 0; border-top: 1px solid var(--line); gap: 8px; }
  .lang-toggle { min-width: 44px; font-size: 13px; }
  .hero-inner { gap: 40px; }
  .split-layout { grid-template-columns: 220px minmax(0, 1fr); gap: 40px; }
  .project-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .section-inner-contact { gap: 40px; }
}

@media (max-width: 760px) {
  :root { --header-height: 72px; --radius: 18px; }
  .site-header { padding-inline: 24px; }
  .section { padding: 60px 24px; }
  .hero { padding-block: 64px; }
  .hero-inner, .split-layout, .section-inner-contact { grid-template-columns: minmax(0, 1fr); gap: 32px; }
  .hero-name { font-size: clamp(43px, 9vw, 68px); }
  .hero-role { font-size: 19px; margin-top: 20px; }
  .hero-text { font-size: 15px; }
  .hero-panel { margin-top: 8px; }
  .signal-list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); column-gap: 24px; }
  .signal-item:nth-child(2) { border-top: 0; }
  .signal-item:last-child { grid-column: 1 / -1; }
  .lead-text { font-size: 22px; }
  .card-grid, .project-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
  .card, .card-link { padding: 24px; }
  .card-clickable { padding: 0; }
  .card-title { font-size: 17px; }
  .card-desc, .card-body { font-size: 13px; }
  .card-index { margin-bottom: 20px; }
  .section-header { margin-bottom: 28px; }
  .timeline { padding-left: 24px; margin-left: 4px; }
  .timeline-point { left: -29px; }
  .timeline-item-current { padding: 22px; }
  .timeline-item-current .timeline-point { left: -30px; top: 30px; }
  .timeline-title { font-size: 17px; }
  .site-footer { padding-inline: 24px; }
}

@media (max-width: 520px) {
  .site-header { padding-inline: 20px; }
  .section { padding-inline: 20px; }
  .brand-text { font-size: 12px; }
  .brand-role { font-size: 10px; }
  .hero-name { font-size: clamp(40px, 11vw, 56px); }
  .hero-actions { align-items: stretch; gap: 10px; }
  .btn { flex: 1 1 140px; padding-inline: 16px; font-size: 12px; }
  .signal-list { display: block; padding-inline: 24px; }
  .signal-item:nth-child(2) { border-top: 1px solid rgba(194, 214, 240, .1); }
  .panel-header { padding-inline: 24px; }
  .panel-education { padding-left: 24px; }
  .card-grid, .project-grid { grid-template-columns: minmax(0, 1fr); }
  .timeline-item-current { padding: 20px; }
  .timeline-title { font-size: 16px; }
  .education-program { font-size: 16px; }
  .icon-button { padding: 14px 10px; gap: 6px; font-size: 12px; }
  .footer-inner { flex-direction: column; gap: 4px; }
}

@media (prefers-reduced-motion: reduce) {
  #vanta-background, #particle-canvas, body::after { display: none; }
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}

@media print {
  :root { color-scheme: light; --background: #fff; --surface: #fff; --text: #111; --muted: #444; --line: #ddd; --accent: #234c7a; }
  #vanta-background, #particle-canvas, body::after, .site-header, .scroll-progress, .skip-link, .hero-actions, .certificate-card::before { display: none; }
  .section { padding: 28px 0; }
  .hero-inner, .split-layout, .section-inner-contact { display: block; }
  .hero-panel, .section-kicker, .contact-text { margin-bottom: 24px; }
  .section-alt, .timeline-item-current, .panel-education { background: #fff; }
  .card, .timeline-item { break-inside: avoid; }
  .hero-panel, .card, .timeline-item-current, .icon-button { background: #fff; box-shadow: none; backdrop-filter: none; -webkit-backdrop-filter: none; border-color: #ddd; }
  .certificate-card .card-link { padding-top: 24px; }
  .hero-name { font-size: 48px; }
}