:root {
  --bg: #08111f;
  --bg-alt: #0d1828;
  --surface: #101d2f;
  --surface-hover: #15253a;
  --border: #22344b;

  --text: #f3f7fb;
  --text-muted: #a8b6c8;
  --text-dim: #74859a;

  --accent: #36a3ff;
  --accent-bright: #62b8ff;
  --accent-soft: rgba(54, 163, 255, 0.12);

  --max-width: 1180px;
  --radius: 16px;
  --transition: 180ms ease;
}

/* --------------------------------------------------
   Base
-------------------------------------------------- */

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

html {
  scroll-behavior: smooth;
}

body {
  font-family:
    Inter,
    ui-sans-serif,
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    sans-serif;

  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: min(92%, var(--max-width));
  margin: 0 auto;
}

.section {
  padding: 100px 0;
}

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

.section-label {
  margin-bottom: 14px;

  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.18em;
}

.section-title {
  max-width: 780px;
  margin-bottom: 50px;

  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.15;
  letter-spacing: -0.035em;
}

p {
  color: var(--text-muted);
}


/* --------------------------------------------------
   Navigation
-------------------------------------------------- */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 100;

  width: 100%;

  background: rgba(8, 17, 31, 0.86);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;

  min-height: 68px;
}

.logo {
  display: flex;
  align-items: center;
  justify-content: center;

  width: 40px;
  height: 40px;

  background: var(--accent-soft);
  border: 1px solid rgba(54, 163, 255, 0.35);
  border-radius: 10px;

  color: var(--accent-bright);
  font-weight: 900;
  letter-spacing: -0.03em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 30px;
}

.nav-links a {
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 600;

  transition:
    color var(--transition),
    transform var(--transition);
}

.nav-links a:hover {
  color: var(--text);
}


/* --------------------------------------------------
   Hero
-------------------------------------------------- */

.hero {
  position: relative;
  display: flex;
  align-items: center;

  min-height: 92vh;
  padding: 150px 0 100px;

  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -180px;
  right: -180px;

  width: 620px;
  height: 620px;

  background:
    radial-gradient(
      circle,
      rgba(54, 163, 255, 0.17) 0%,
      rgba(54, 163, 255, 0.06) 42%,
      transparent 70%
    );

  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: -280px;
  left: -220px;

  width: 540px;
  height: 540px;

  background:
    radial-gradient(
      circle,
      rgba(43, 99, 255, 0.10) 0%,
      transparent 70%
    );

  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.eyebrow {
  margin-bottom: 24px;

  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.18em;
}

.hero h1 {
  max-width: 900px;

  font-size: clamp(3.5rem, 9vw, 7rem);
  line-height: 0.97;
  letter-spacing: -0.065em;
}

.hero h2 {
  max-width: 850px;
  margin-top: 28px;

  color: #c9d6e4;
  font-size: clamp(1.4rem, 3vw, 2.25rem);
  font-weight: 500;
  line-height: 1.35;
  letter-spacing: -0.025em;
}

.hero-copy {
  max-width: 700px;
  margin-top: 24px;

  font-size: 1.08rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;

  margin-top: 34px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;

  min-height: 48px;
  padding: 0 20px;

  border: 1px solid var(--border);
  border-radius: 10px;

  color: var(--text);
  font-size: 0.9rem;
  font-weight: 700;

  transition:
    background var(--transition),
    border-color var(--transition),
    transform var(--transition);
}

.button:hover {
  background: var(--surface);
  border-color: #38506d;
  transform: translateY(-2px);
}

.button-primary {
  background: var(--accent);
  border-color: var(--accent);

  color: #03101c;
}

.button-primary:hover {
  background: var(--accent-bright);
  border-color: var(--accent-bright);
}


/* --------------------------------------------------
   About / Expertise
-------------------------------------------------- */

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1.15fr;
  gap: 70px;
  align-items: start;
}

.about-copy p {
  margin-bottom: 22px;

  font-size: 1.02rem;
}

.expertise-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}

.expertise-card {
  min-height: 165px;
  padding: 24px;

  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);

  transition:
    background var(--transition),
    border-color var(--transition),
    transform var(--transition);
}

.expertise-card:hover {
  background: var(--surface-hover);
  border-color: #34516f;
  transform: translateY(-3px);
}

.expertise-card h3 {
  margin-bottom: 10px;

  font-size: 1.05rem;
}

.expertise-card p {
  font-size: 0.92rem;
}


/* --------------------------------------------------
   Projects
-------------------------------------------------- */

.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.project-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;

  min-height: 440px;
  padding: 30px;

  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);

  transition:
    background var(--transition),
    border-color var(--transition),
    transform var(--transition);
}

.project-card:hover {
  background: var(--surface-hover);
  border-color: #34516f;
  transform: translateY(-5px);
}

.project-number {
  margin-bottom: 28px;

  color: var(--accent);
  font-family: monospace;
  font-size: 0.82rem;
  font-weight: 700;
}

.project-card h3 {
  margin-bottom: 18px;

  font-size: 1.45rem;
  line-height: 1.2;
  letter-spacing: -0.025em;
}

.project-card p {
  font-size: 0.94rem;
}

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

  margin-top: 32px;
  margin-bottom: 26px;
}

.tags span {
  padding: 5px 9px;

  background: var(--accent-soft);
  border: 1px solid rgba(54, 163, 255, 0.2);
  border-radius: 6px;

  color: #99d3ff;
  font-size: 0.72rem;
  font-weight: 700;
}

.project-link {
  display: inline-block;

  color: var(--accent-bright);
  font-size: 0.88rem;
  font-weight: 800;

  transition: transform var(--transition);
}

.project-link:hover {
  transform: translateX(4px);
}


/* --------------------------------------------------
   Experience
-------------------------------------------------- */

.timeline {
  max-width: 900px;
}

.experience-item {
  padding: 34px 0;

  border-top: 1px solid var(--border);
}

.experience-item:last-child {
  border-bottom: 1px solid var(--border);
}

.experience-heading {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 24px;

  margin-bottom: 18px;
}

.experience-heading h3 {
  font-size: 1.35rem;
  letter-spacing: -0.02em;
}

.company {
  margin-top: 2px;

  color: var(--accent);
  font-weight: 700;
}

.date {
  flex-shrink: 0;

  color: var(--text-dim);
  font-size: 0.86rem;
}

.experience-item > p {
  max-width: 800px;
  margin-bottom: 18px;
}

.experience-item ul {
  padding-left: 20px;

  color: var(--text-muted);
}

.experience-item li {
  margin: 7px 0;
  padding-left: 4px;
}


/* --------------------------------------------------
   Certifications
-------------------------------------------------- */

.cert-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.cert-card {
  display: flex;
  flex-direction: column;
  gap: 10px;

  min-height: 145px;
  padding: 24px;

  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.cert-card strong {
  color: var(--accent);
  font-family: monospace;
  font-size: 1.1rem;
}

.cert-card span {
  color: var(--text-muted);
  font-size: 0.92rem;
  font-weight: 600;
}


/* --------------------------------------------------
   Contact
-------------------------------------------------- */

.contact {
  text-align: center;
}

.contact .section-label {
  text-align: center;
}

.contact h2 {
  max-width: 760px;
  margin: 0 auto;

  font-size: clamp(2rem, 5vw, 3.6rem);
  line-height: 1.12;
  letter-spacing: -0.045em;
}

.contact > .container > p:not(.section-label) {
  max-width: 620px;
  margin: 24px auto 0;
}

.contact .hero-actions {
  justify-content: center;
}


/* --------------------------------------------------
   Footer
-------------------------------------------------- */

footer {
  padding: 28px 0;

  border-top: 1px solid var(--border);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  gap: 20px;
}

.footer-content p {
  color: var(--text-dim);
  font-size: 0.82rem;
}

.visitor-placeholder {
  color: #587088;
}


/* --------------------------------------------------
   Focus / accessibility
-------------------------------------------------- */

a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
  border-radius: 4px;
}


/* --------------------------------------------------
   Responsive
-------------------------------------------------- */

@media (max-width: 960px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 42px;
  }

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

  .project-card {
    min-height: auto;
  }

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

@media (max-width: 700px) {
  .section {
    padding: 76px 0;
  }

  .nav {
    min-height: 62px;
  }

  .nav-links {
    gap: 15px;
  }

  .nav-links a {
    font-size: 0.78rem;
  }

  .nav-links a:first-child,
  .nav-links a:last-child {
    display: none;
  }

  .hero {
    min-height: auto;
    padding: 135px 0 90px;
  }

  .hero h1 {
    font-size: clamp(3.2rem, 16vw, 5rem);
  }

  .hero h2 {
    font-size: 1.35rem;
  }

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

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

  .experience-heading {
    flex-direction: column;
    gap: 8px;
  }

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

  .hero-actions .button {
    flex: 1;
  }
}

@media (max-width: 450px) {
  .hero-actions {
    flex-direction: column;
  }

  .hero-actions .button {
    width: 100%;
  }

  .project-card {
    padding: 24px;
  }
}

/* --------------------------------------------------
   Site infrastructure callout
-------------------------------------------------- */

.site-stack {
  display: inline-flex;
  align-items: center;
  gap: 14px;

  margin-top: 38px;
  padding: 13px 16px;

  background: rgba(16, 29, 47, 0.72);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.site-stack-icon {
  display: flex;
  align-items: center;
  justify-content: center;

  width: 38px;
  height: 38px;

  background: var(--accent-soft);
  border: 1px solid rgba(54, 163, 255, 0.35);
  border-radius: 8px;

  color: var(--accent-bright);
  font-family: monospace;
  font-size: 0.78rem;
  font-weight: 800;
}

.site-stack-copy {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.site-stack-label {
  color: var(--accent);
  font-size: 0.67rem;
  font-weight: 800;
  letter-spacing: 0.14em;
}

.site-stack-detail {
  color: var(--text-muted);
  font-size: 0.82rem;
  font-weight: 600;
}

.site-stack-detail span {
  margin: 0 4px;
  color: var(--text-dim);
}

@media (max-width: 450px) {
  .site-stack {
    width: 100%;
  }
}

/* --------------------------------------------------
   Mobile browser / safe-area refinement
-------------------------------------------------- */

@media (max-width: 700px) {
  .site-header {
    position: sticky;
    top: 0;
    padding-top: env(safe-area-inset-top);
  }

  .hero {
    padding-top: 72px;
  }
}