:root {
  --bg: #050507;
  --panel: rgba(20, 20, 25, .76);
  --border: rgba(255, 255, 255, .09);
  --primary: #60a5fa;
  --primary-strong: #3b82f6;
  --text: #f1f5f9;
  --muted: #a5b4c7;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg) radial-gradient(circle at 60% -20%, #1e293b 0, #0a0a0c 70%) fixed;
  line-height: 1.75;
}
.container { width: min(100% - 48px, 920px); margin-inline: auto; }
.header-fixed {
  position: fixed;
  inset: 0 0 auto;
  z-index: 1000;
  background: rgba(5, 5, 7, .88);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(16px);
}
.nav-container {
  width: min(100% - 48px, 1200px);
  min-height: 82px;
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.logo-img { display: block; width: auto; height: 56px; }
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--primary);
  font-size: .9rem;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
}
.back-link:hover, .back-link:focus-visible { color: #bfdbfe; }
.article-section { padding: 130px 0 80px; }
.breadcrumbs {
  margin: 0 0 16px;
  color: var(--muted);
  font-size: .82rem;
}
.breadcrumbs a { color: var(--primary); text-decoration: none; }
.breadcrumbs span { margin-inline: 8px; }
.glass-panel {
  padding: 48px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 20px;
  box-shadow: 0 20px 42px rgba(0, 0, 0, .32);
  backdrop-filter: blur(12px);
}
h1, h2, h3 { font-family: Outfit, Inter, sans-serif; }
h1 {
  margin: 0 0 20px;
  color: #fff;
  font-size: clamp(1.85rem, 4vw, 2.45rem);
  line-height: 1.2;
  text-wrap: balance;
}
h2 {
  margin: 42px 0 16px;
  padding-bottom: 8px;
  color: var(--primary);
  border-bottom: 1px solid var(--border);
  font-size: 1.5rem;
  line-height: 1.3;
}
h3 { margin: 28px 0 12px; color: #fff; font-size: 1.15rem; }
p { margin: 0 0 18px; }
.meta-info {
  margin-bottom: 22px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border);
}
.author-link { color: #fff; font-family: Outfit, sans-serif; font-weight: 600; text-decoration: none; }
.author-link:hover, .author-link:focus-visible { color: #bfdbfe; }
.meta-sub, .publication-dates { color: var(--muted); font-size: .86rem; line-height: 1.55; }
.publication-dates { margin-top: 7px; }
.article-subtitle { margin: 0 0 28px; color: var(--muted); font-size: 1.08rem; line-height: 1.65; }
.article-lead { color: #e2e8f0; font-size: 1.08rem; }
.glass-panel p, .glass-panel li { font-weight: 300; }
.glass-panel ul, .glass-panel ol { margin: 0 0 24px; padding-left: 24px; }
.glass-panel li { margin-bottom: 10px; }
.glass-panel a { color: var(--primary); text-decoration-thickness: 1px; text-underline-offset: 3px; }
.glass-panel a:hover, .glass-panel a:focus-visible { color: #bfdbfe; }
.formula {
  overflow-x: auto;
  margin: 24px 0;
  padding: 18px 22px;
  color: #fff;
  background: rgba(59, 130, 246, .07);
  border: 1px solid var(--border);
  border-left: 4px solid var(--primary-strong);
  border-radius: 0 12px 12px 0;
  font-family: "Cambria Math", "Times New Roman", serif;
  font-size: 1.05rem;
}
.references { margin-top: 46px; }
.references p { color: var(--muted); font-size: .88rem; overflow-wrap: anywhere; }
footer { padding: 38px 0; color: var(--muted); border-top: 1px solid var(--border); text-align: center; font-size: .88rem; }
footer p { margin: 0; }
:focus-visible { outline: 3px solid rgba(96, 165, 250, .75); outline-offset: 3px; }

@media (max-width: 720px) {
  .container, .nav-container { width: min(100% - 28px, 920px); }
  .nav-container { min-height: 72px; }
  .logo-img { height: 47px; }
  .back-link { font-size: .82rem; }
  .article-section { padding-top: 105px; }
  .glass-panel { padding: 26px 20px; border-radius: 15px; }
  h2 { font-size: 1.28rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}