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

:root {
  --color-primary: #18181b;
  --color-secondary: #3f3f46;
  --color-accent: #2563eb;
  --color-bg: #fafafa;
  --color-text: #09090b;
  --color-muted: #71717a;
  --color-border: #e4e4e7;
  --color-surface: #ffffff;
  --color-orange: #ec8a00;
  --color-red: #e5391f;
  --font-serif: "Crimson Pro", "Noto Serif SC", Georgia, serif;
  --font-sans: "Atkinson Hyperlegible", "Noto Sans SC", system-ui, sans-serif;
  --max-width: 1160px;
}

html {
  font-size: 17px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--color-primary);
  background:
    linear-gradient(180deg, rgba(236, 138, 0, 0.03), transparent 220px),
    var(--color-bg);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a {
  color: var(--color-accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease, color 0.2s ease;
}

a:hover,
a:focus-visible {
  border-bottom-color: var(--color-accent);
}

a:focus-visible {
  outline: 2px solid rgba(37, 99, 235, 0.35);
  outline-offset: 3px;
}

.site-nav {
  display: flex;
  justify-content: center;
  gap: 2rem;
  padding: 0.9rem 1.5rem;
  border-bottom: 1px solid var(--color-border);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 10;
}

.nav-item {
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-muted);
}

a.nav-item:hover,
a.nav-item:focus-visible {
  color: var(--color-accent);
  border-bottom-color: transparent;
}

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

.nav-item.lang-switch {
  color: var(--color-accent);
  border: 1px solid var(--color-accent);
  border-radius: 4px;
  padding: 0.1rem 0.5rem;
  font-size: 0.75rem;
}

.nav-item.lang-switch:hover {
  background: var(--color-accent);
  color: #fff;
  border-bottom-color: var(--color-accent);
}

/* ── Index page ── */

main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 4rem 1.5rem 4.5rem;
}

.hero {
  margin-bottom: 3.2rem;
  text-align: center;
}

.hero h1 {
  display: inline-block;
  margin: 0;
  font-family: var(--font-sans);
  font-size: clamp(1.2rem, 6.4vw, 4.95rem);
  font-weight: 700;
  line-height: 0.98;
  letter-spacing: -0.06em;
  white-space: nowrap;
  color: var(--color-orange);
}

.hero h1 .accent {
  color: var(--color-red);
}

.content {
  display: grid;
  gap: 2.4rem;
}

section h2 {
  margin: 0 0 0.85rem;
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--color-primary);
}

p {
  margin: 0 0 1rem;
  color: var(--color-secondary);
}

p:last-child {
  margin-bottom: 0;
}

.links-list {
  margin: 0;
  padding-left: 1.2rem;
  color: var(--color-secondary);
}

.links-list li + li {
  margin-top: 0.65rem;
}

.intro-figure {
  margin: 1.5rem 0 0;
  border: 1px solid var(--color-border);
  border-radius: 22px;
  overflow: hidden;
  background: #ffffff;
}

.intro-figure img {
  display: block;
  width: 100%;
  height: auto;
}

/* ── About page ── */

.page-about main {
  max-width: 920px;
}

.about-intro {
  margin-bottom: 1.4rem;
  font-family: var(--font-serif);
  font-size: 1.05rem;
  line-height: 1.86;
  color: var(--color-primary);
}

.contributors-list {
  border-top: 1px solid var(--color-border);
  margin-top: 0.35rem;
}

.contributor-item {
  display: grid;
  grid-template-columns: 190px 1fr;
  gap: 1rem;
  align-items: baseline;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--color-border);
}

.contributor-item.no-detail {
  grid-template-columns: 1fr;
}

.contributor-name {
  font-family: var(--font-serif);
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--color-primary);
}

.contributor-role {
  margin: 0;
  font-size: 0.89rem;
  line-height: 1.6;
  color: var(--color-muted);
}

.acknowledgements {
  margin-top: 1.8rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
  font-size: 0.92rem;
  line-height: 1.85;
  color: var(--color-muted);
  font-style: italic;
}

/* ── Footer ── */

.site-footer {
  padding: 1.8rem 1.5rem 2rem;
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-size: 0.8rem;
  color: var(--color-muted);
}

.site-footer a {
  color: var(--color-secondary);
}

/* ── Responsive ── */

@media (max-width: 720px) {
  html {
    font-size: 16px;
  }

  .site-nav {
    gap: 1rem;
    flex-wrap: wrap;
  }

  main {
    padding-top: 3rem;
  }

  .contributor-item {
    grid-template-columns: 1fr;
    gap: 0.15rem;
  }
}

@media (max-width: 420px) {
  .hero h1 {
    letter-spacing: -0.045em;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }

  html {
    scroll-behavior: auto;
  }
}