:root {
  color-scheme: light;
  --ink: #17202f;
  --muted: #5d687a;
  --line: #d8e0ea;
  --panel: #f7f9fc;
  --accent: #0f5b78;
  --accent-2: #b56b31;
  --soft-blue: #e8f1f5;
  --white: #ffffff;
  --shadow: 0 18px 45px rgba(23, 32, 47, 0.10);
  font-family: Arial, Helvetica, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height, 100px);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-size: 16px;
  line-height: 1.6;
}

a {
  color: inherit;
}

img {
  display: block;
  max-width: 100%;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px clamp(20px, 5vw, 72px);
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid rgba(216, 224, 234, 0.86);
  backdrop-filter: blur(18px);
}

.brand {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 44px;
  height: 44px;
  place-items: center;
  color: var(--white);
  background: var(--accent);
  border-radius: 8px;
  font-weight: 800;
}

.brand strong,
.brand small {
  display: block;
}

.brand small {
  color: var(--muted);
  font-size: 0.82rem;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 6px;
}

.site-nav a {
  padding: 10px 12px;
  color: var(--muted);
  text-decoration: none;
  border-radius: 8px;
  font-size: 0.92rem;
  white-space: nowrap;
}

.site-nav a:hover,
.site-nav a:focus-visible,
.site-nav a[aria-current="location"],
.site-nav a[aria-current="page"] {
  color: var(--accent);
  background: var(--soft-blue);
}

.nav-toggle {
  display: none;
  border: 1px solid var(--line);
  background: var(--white);
  border-radius: 8px;
  padding: 9px 12px;
  color: var(--ink);
}

.hero {
  display: grid;
  grid-template-columns: minmax(260px, 0.75fr) minmax(0, 1.25fr);
  gap: clamp(32px, 4vw, 64px);
  align-items: center;
  min-height: 560px;
  padding: 64px max(24px, calc((100vw - 1200px) / 2));
  background-image:
    linear-gradient(90deg, rgba(255, 255, 255, 0.96), rgba(255, 255, 255, 0.88) 45%, rgba(255, 255, 255, 0.78)),
    url("assets/network-planning.png");
  background-position: center;
  background-size: cover;
  background-repeat: no-repeat;
}

.eyebrow,
.section-label {
  margin: 0 0 10px;
  color: var(--accent-2);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 840px;
  margin-bottom: 12px;
  font-size: clamp(2.55rem, 4.5vw, 4rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
}

.hero-role {
  margin-bottom: 24px;
  color: var(--accent);
  font-size: clamp(1.15rem, 2vw, 1.45rem);
}

h2 {
  margin-bottom: 18px;
  font-size: clamp(2rem, 3.4vw, 3.25rem);
  line-height: 1.05;
}

h3 {
  margin-bottom: 8px;
  font-size: 1.1rem;
  line-height: 1.25;
}

.hero-text {
  max-width: 580px;
  color: var(--muted);
  font-size: 1.18rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 18px;
  border: 1px solid var(--accent);
  border-radius: 8px;
  font-weight: 800;
  text-decoration: none;
}

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

.button.secondary {
  color: var(--accent);
  background: rgba(255, 255, 255, 0.72);
}

.cv-download {
  position: relative;
}

.cv-download summary {
  gap: 10px;
  cursor: pointer;
  list-style: none;
}

.cv-download summary::-webkit-details-marker {
  display: none;
}

.cv-options {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  z-index: 2;
  min-width: 210px;
  padding: 6px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.cv-options a {
  display: block;
  padding: 10px 12px;
  color: var(--accent);
  text-decoration: none;
  border-radius: 4px;
}

.cv-options a:hover,
.cv-options a:focus-visible {
  background: var(--soft-blue);
}

.hero-portrait {
  order: -1;
  margin: 0;
  width: min(100%, 340px);
  justify-self: center;
}

.hero-portrait img {
  width: 100%;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.section {
  padding: 72px clamp(20px, 5vw, 72px);
  border-top: 1px solid var(--line);
}

.two-column {
  display: grid;
  grid-template-columns: minmax(220px, 0.75fr) minmax(0, 1.25fr);
  gap: clamp(28px, 5vw, 72px);
}

.flow p {
  color: var(--muted);
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.tag-list span {
  padding: 8px 10px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  font-size: 0.92rem;
  font-weight: 700;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 34px;
}

.writing-page {
  max-width: 900px;
  min-height: 65vh;
  margin: 0 auto;
  padding: clamp(40px, 7vw, 80px) 24px;
}

.writing-page h1 {
  font-size: clamp(2rem, 4vw, 3rem);
}

.article-index {
  list-style: none;
  padding: 0;
  margin: 32px 0;
}

.article-index li {
  padding: 20px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.article-index a,
.back-link {
  color: var(--accent);
  text-underline-offset: 4px;
}

.article-index a {
  font-size: 1.25rem;
}

.article-body {
  max-width: 720px;
  font-size: 1.12rem;
  line-height: 1.85;
}

.article-figure {
  margin: 32px 0;
}

.article-figure img {
  width: 100%;
  height: auto;
}

.back-link {
  display: inline-block;
  margin-bottom: 28px;
}

.timeline {
  display: grid;
  gap: 18px;
}

.timeline-item {
  display: grid;
  grid-template-columns: 170px minmax(0, 1fr);
  gap: 22px;
}

.timeline-date {
  color: var(--accent);
  font-weight: 800;
}

.timeline-card,
.card,
.publication-list article,
.contact-card {
  padding: 24px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 8px 26px rgba(23, 32, 47, 0.05);
}

.timeline-card ul {
  margin: 12px 0 0;
  padding-left: 22px;
  color: var(--muted);
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.card p {
  color: var(--muted);
}

.publication-list {
  display: grid;
  gap: 14px;
}

.publication-list a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

.publication-list p {
  margin-bottom: 0;
  color: var(--muted);
}

.contact {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(300px, 460px);
  gap: clamp(28px, 5vw, 72px);
  background: var(--panel);
}

.contact-card {
  display: grid;
  gap: 10px;
  align-content: start;
}

.contact-card a {
  color: var(--accent);
  font-weight: 800;
}

.contact-card p {
  margin-bottom: 0;
  color: var(--muted);
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 26px clamp(20px, 5vw, 72px);
  color: var(--muted);
  border-top: 1px solid var(--line);
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  color: var(--accent);
  font-weight: 800;
}

@media (max-width: 1200px) {
  .site-header {
    align-items: flex-start;
    flex-wrap: wrap;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    display: none;
    flex-basis: 100%;
    flex-direction: column;
    align-items: stretch;
  }

  .site-nav.is-open {
    display: flex;
  }
}

@media (max-width: 860px) {

  .hero,
  .two-column,
  .timeline-item,
  .contact {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
  }

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

@media (max-width: 560px) {
  h1 {
    font-size: 2.45rem;
  }

  .site-footer {
    flex-direction: column;
  }
}