:root {
  --uxsl-bg: #f4f7fb;
  --uxsl-surface: rgba(255, 255, 255, 0.82);
  --uxsl-card: rgba(255, 255, 255, 0.92);
  --uxsl-text: #1b2432;
  --uxsl-heading: #13348f;
  --uxsl-navy: #13348f;
  --uxsl-blue: #0057ff;
  --uxsl-blue-dark: #003fc0;
  --uxsl-muted: #5f6b85;
  --uxsl-border: rgba(19, 52, 143, 0.1);
  --uxsl-shadow: 0 18px 40px rgba(19, 52, 143, 0.08);
  --uxsl-shadow-strong: 0 24px 60px rgba(19, 52, 143, 0.14);
  --uxsl-radius: 28px;
  --uxsl-radius-sm: 18px;
  --uxsl-max: 1200px;
  --uxsl-reading: 760px;
  --uxsl-header-height: 84px;
  --uxsl-font: "Open Sans", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--uxsl-font);
  background:
    radial-gradient(circle at top left, rgba(0, 87, 255, 0.08), transparent 30%),
    radial-gradient(circle at top right, rgba(19, 52, 143, 0.08), transparent 28%),
    linear-gradient(180deg, #f8fbff 0%, #eef4fb 100%);
  color: var(--uxsl-text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--uxsl-blue);
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease;
}

a:hover,
a:focus-visible {
  color: var(--uxsl-blue-dark);
}

p,
li {
  font-size: 1.04rem;
}

h1,
h2,
h3,
h4 {
  margin: 0 0 16px;
  line-height: 1.15;
  color: var(--uxsl-heading);
}

h1 {
  font-size: clamp(2.4rem, 5vw, 4.25rem);
  letter-spacing: -0.03em;
}

h2 {
  font-size: clamp(1.7rem, 3vw, 2.4rem);
  letter-spacing: -0.02em;
}

h3 {
  font-size: clamp(1.15rem, 2vw, 1.45rem);
}

.container {
  width: min(100% - 32px, var(--uxsl-max));
  margin: 0 auto;
}

.narrow {
  width: min(100% - 32px, var(--uxsl-reading));
  margin: 0 auto;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 9999;
  padding: 12px 16px;
  background: #fff;
  color: var(--uxsl-blue);
  border-radius: 12px;
  box-shadow: var(--uxsl-shadow);
}

.skip-link:focus {
  top: 16px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(18px);
  background: rgba(255, 255, 255, 0.78);
  border-bottom: 1px solid rgba(19, 52, 143, 0.08);
}

.header-inner {
  min-height: var(--uxsl-header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.header-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--uxsl-heading);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.header-brand img,
.header-brand-img {
  width: 44px;
  height: 44px;
  object-fit: contain;
}

.header-brand-text {
  font-size: 1.05rem;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.site-nav a {
  color: var(--uxsl-text);
  font-weight: 700;
  font-size: 0.96rem;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: var(--uxsl-blue);
}

.nav-toggle {
  display: none;
  width: 48px;
  height: 48px;
  padding: 0;
  border: 1px solid var(--uxsl-border);
  background: rgba(255, 255, 255, 0.85);
  border-radius: 14px;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  margin: 5px auto;
  background: var(--uxsl-heading);
  border-radius: 999px;
}

.hero {
  position: relative;
  padding: 88px 0 52px;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 10% 10%, rgba(0, 87, 255, 0.12), transparent 22%),
    radial-gradient(circle at 90% 10%, rgba(19, 52, 143, 0.09), transparent 20%);
}

.hero-inner {
  width: min(100% - 32px, 1040px);
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

.hero-logo {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  padding: 12px 18px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(19, 52, 143, 0.08);
  box-shadow: var(--uxsl-shadow);
  margin-bottom: 26px;
}

.hero-logo-img {
  width: 44px;
  height: 44px;
  object-fit: contain;
}

.hero-logo-text {
  color: var(--uxsl-heading);
  font-weight: 800;
}

.eyebrow {
  margin: 0 0 12px;
  font-size: 0.82rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--uxsl-blue);
}

.lead {
  font-size: clamp(1.08rem, 1.8vw, 1.3rem);
  color: var(--uxsl-muted);
  max-width: 760px;
  margin: 0 auto;
}

.hero-copy,
.article-hero-copy {
  max-width: 900px;
  margin: 0 auto;
  text-align: center;
}

.article-hero-meta {
  margin-top: 18px;
  color: var(--uxsl-muted);
  font-size: 0.96rem;
  font-weight: 600;
}

.hero-cta,
.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 28px;
}

.hero-cta {
  justify-content: center;
}

.button-row.centered {
  justify-content: center;
}

.btn-primary,
.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 0 22px;
  border-radius: 999px;
  font-weight: 800;
  font-size: 0.98rem;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;
}

.btn-primary {
  color: #fff;
  background: linear-gradient(135deg, var(--uxsl-blue) 0%, #2d72ff 100%);
  box-shadow: 0 16px 36px rgba(0, 87, 255, 0.22);
}

.btn-primary:hover,
.btn-primary:focus-visible {
  color: #fff;
  transform: translateY(-1px);
  background: linear-gradient(135deg, var(--uxsl-blue-dark) 0%, #1256e8 100%);
}

.btn-secondary {
  color: var(--uxsl-heading);
  background: rgba(255, 255, 255, 0.84);
  border: 1px solid rgba(19, 52, 143, 0.1);
  box-shadow: var(--uxsl-shadow);
}

.btn-secondary:hover,
.btn-secondary:focus-visible {
  transform: translateY(-1px);
  color: var(--uxsl-blue);
}

.section {
  padding: 60px 0;
}

.accent-section {
  background: linear-gradient(180deg, rgba(255,255,255,0.32) 0%, rgba(228, 239, 255, 0.5) 100%);
  border-top: 1px solid rgba(19, 52, 143, 0.06);
  border-bottom: 1px solid rgba(19, 52, 143, 0.06);
}

.article-shell {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(280px, 0.78fr);
  gap: 32px;
  align-items: start;
}

.article-main {
  min-width: 0;
}

.article-sidebar {
  position: sticky;
  top: calc(var(--uxsl-header-height) + 24px);
}

.article-prose {
  padding: 34px;
  background: var(--uxsl-card);
  border: 1px solid var(--uxsl-border);
  border-radius: var(--uxsl-radius);
  box-shadow: var(--uxsl-shadow);
}

.article-prose p {
  margin: 0 0 18px;
}

.article-prose h2 {
  margin-top: 42px;
  margin-bottom: 14px;
}

.article-prose h3 {
  margin-top: 28px;
  margin-bottom: 10px;
}

.article-prose ul,
.article-prose ol {
  margin: 0 0 22px 22px;
  padding: 0;
}

.article-prose li {
  margin-bottom: 10px;
}

.article-prose strong {
  color: var(--uxsl-heading);
}

.article-prose blockquote,
.article-quote {
  margin: 28px 0;
  padding: 22px 24px;
  border-left: 4px solid var(--uxsl-blue);
  background: rgba(255, 255, 255, 0.76);
  border-radius: 18px;
  color: var(--uxsl-heading);
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1.55;
}

.article-callout {
  margin: 28px 0;
  padding: 24px;
  border-radius: 22px;
  background: linear-gradient(180deg, rgba(255,255,255,0.94) 0%, rgba(236,244,255,0.94) 100%);
  border: 1px solid rgba(0, 87, 255, 0.12);
  box-shadow: var(--uxsl-shadow);
}

.article-callout p:last-child {
  margin-bottom: 0;
}

.article-card,
.card {
  padding: 24px;
  background: var(--uxsl-card);
  border: 1px solid var(--uxsl-border);
  border-radius: var(--uxsl-radius);
  box-shadow: var(--uxsl-shadow);
}

.article-card + .article-card {
  margin-top: 18px;
}

.article-card h2,
.article-card h3,
.card h3 {
  color: var(--uxsl-heading);
  margin-top: 0;
}

.article-mini-list {
  display: grid;
  gap: 12px;
  margin: 16px 0 0;
  padding-left: 18px;
}

.related-links {
  display: grid;
  gap: 14px;
  margin-top: 18px;
}

.related-links a {
  color: var(--uxsl-heading);
  font-weight: 700;
}

.related-links a:hover,
.related-links a:focus-visible {
  color: var(--uxsl-blue);
}

.card-grid {
  display: grid;
  gap: 20px;
}

.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.contact-section .narrow,
.intro-section .narrow {
  text-align: center;
}

.post-hero-content,
#post-hero-content {
  display: block;
}

.post-hero-content.is-hidden,
#post-hero-content.is-hidden {
  display: none;
}

hr {
  border: 0;
  height: 1px;
  background: rgba(19, 52, 143, 0.08);
  margin: 32px 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  overflow: hidden;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: var(--uxsl-shadow);
}

th,
td {
  padding: 14px 16px;
  border-bottom: 1px solid rgba(19, 52, 143, 0.08);
  text-align: left;
}

th {
  color: var(--uxsl-heading);
  background: rgba(236, 244, 255, 0.8);
  font-weight: 800;
}

code,
pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

code {
  padding: 2px 8px;
  background: rgba(19, 52, 143, 0.07);
  border-radius: 8px;
  font-size: 0.92em;
}

pre {
  overflow-x: auto;
  padding: 18px;
  background: #0f1a36;
  color: #e9efff;
  border-radius: 18px;
  box-shadow: var(--uxsl-shadow);
}

.site-footer {
  padding: 30px 0 46px;
  border-top: 1px solid rgba(19, 52, 143, 0.08);
  background: rgba(255, 255, 255, 0.4);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  flex-wrap: wrap;
}

.footer-inner p {
  margin: 0;
  color: var(--uxsl-muted);
  font-size: 0.95rem;
}

@media (max-width: 1120px) {
  .grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 980px) {
  .article-shell {
    grid-template-columns: 1fr;
  }

  .article-sidebar {
    position: static;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 10px);
    right: 16px;
    left: 16px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 10px;
    background: rgba(255, 255, 255, 0.96);
    border: 1px solid rgba(19, 52, 143, 0.1);
    border-radius: 22px;
    box-shadow: var(--uxsl-shadow-strong);
  }

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

  .site-nav a {
    padding: 14px 12px;
    border-radius: 14px;
  }

  .site-nav a:hover,
  .site-nav a:focus-visible {
    background: rgba(236, 244, 255, 0.9);
  }

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

@media (max-width: 760px) {
  .hero {
    padding: 72px 0 40px;
  }

  .section {
    padding: 48px 0;
  }

  .article-prose,
  .article-card,
  .card {
    padding: 22px;
  }

  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 520px) {
  .container,
  .narrow,
  .hero-inner {
    width: min(100% - 20px, var(--uxsl-max));
  }

  .header-inner {
    gap: 12px;
  }

  .header-brand-text {
    font-size: 0.95rem;
  }

  .btn-primary,
  .btn-secondary {
    width: 100%;
  }

  .article-prose p,
  .article-prose li,
  p,
  li {
    font-size: 1rem;
  }
}

.hero-simple {
  padding: 72px 0 26px;
}

.hero-simple .hero-inner {
  width: min(100% - 32px, 900px);
}

.hero-simple .article-hero-copy {
  max-width: 820px;
  margin: 0 auto;
  text-align: center;
}

.hero-simple .lead {
  max-width: 760px;
}

.site-nav {
  gap: 0;
}

.site-nav a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 0 16px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(19, 52, 143, 0.1);
  box-shadow: var(--uxsl-shadow);
}

.site-nav a:hover,
.site-nav a:focus-visible {
  background: rgba(236, 244, 255, 0.92);
}

.post-hero-content,
#post-hero-content {
  display: block;
}

.article-list {
  display: grid;
  gap: 20px;
  margin-top: 28px;
}

.article-list-card {
  padding: 26px;
  background: var(--uxsl-card);
  border: 1px solid var(--uxsl-border);
  border-radius: var(--uxsl-radius);
  box-shadow: var(--uxsl-shadow);
}

.article-list-card h2 {
  margin-bottom: 10px;
}

.article-list-card p {
  margin: 0 0 14px;
}

.article-list-meta {
  margin-bottom: 10px;
  font-size: 0.95rem;
  color: var(--uxsl-muted);
  font-weight: 600;
}

.article-list-link {
  font-weight: 800;
}

@media (max-width: 760px) {
  .hero-simple {
    padding: 56px 0 18px;
  }

  .header-inner {
    gap: 16px;
  }
}

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

.back-to-articles {
  font-size: 14px;
  font-weight: 500;
  color: #555;
  text-decoration: none;
}

.back-to-articles:hover {
  text-decoration: underline;
}