:root {
  --ink: #102a43;
  --muted: #486581;
  --blue: #087eaf;
  --blue-dark: #075f86;
  --mint: #23c7a3;
  --mint-soft: #edfcf8;
  --line: #d9ecff;
  --soft: #f3f9fd;
  --white: #ffffff;
  --shadow: 0 20px 55px rgba(15, 54, 80, 0.09);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  overflow-wrap: anywhere;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 8% 2%, rgba(71, 229, 188, 0.09), transparent 25rem),
    linear-gradient(180deg, #f8fcff 0, var(--soft) 30rem);
  font-family: "Segoe UI", Arial, sans-serif;
  font-size: 18px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
}

.skip-link {
  position: fixed;
  left: 1rem;
  top: -5rem;
  z-index: 10;
  padding: 0.75rem 1rem;
  color: var(--white);
  background: var(--ink);
  border-radius: 0.75rem;
}

.skip-link:focus { top: 1rem; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  min-height: 76px;
  padding: 0.8rem max(5vw, 1rem);
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid rgba(217, 236, 255, 0.9);
  backdrop-filter: blur(14px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--ink);
  font-size: 1.25rem;
  font-weight: 900;
  text-decoration: none;
}

.brand::before {
  content: "AD";
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  color: var(--white);
  background: linear-gradient(135deg, var(--blue), #3fa9f5);
  border-radius: 14px;
  box-shadow: 0 8px 20px rgba(8, 126, 175, 0.22);
  font-size: 0.85rem;
  letter-spacing: 0.03em;
}

.site-header nav {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.site-header nav a {
  padding: 0.55rem 0.8rem;
  color: var(--blue-dark);
  border-radius: 999px;
  font-weight: 750;
  text-decoration: none;
}

.site-header nav a:hover,
.site-header nav a[aria-current="page"] { background: #eaf7ff; }

a {
  color: #076f9f;
  text-decoration-thickness: 1.5px;
  text-underline-offset: 3px;
}

a:hover { color: var(--blue-dark); }

a:focus-visible,
.button:focus-visible {
  outline: 3px solid rgba(35, 199, 163, 0.6);
  outline-offset: 3px;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 820px) minmax(250px, 300px);
  gap: 2rem;
  align-items: start;
  max-width: 1200px;
  margin: 2.5rem auto 4rem;
  padding: 0 1.25rem;
}

.article-card,
.related,
.index-hero,
.article-preview {
  background: rgba(255, 255, 255, 0.98);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.article-card {
  min-width: 0;
  padding: clamp(1.4rem, 4vw, 3.4rem);
  border-radius: 30px;
}

.article-card > h1:first-child {
  position: relative;
  padding-bottom: 1.25rem;
}

.article-card > h1:first-child::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 76px;
  height: 5px;
  background: linear-gradient(90deg, var(--mint), var(--blue));
  border-radius: 999px;
}

.article-card > h1:first-child + p {
  color: #284f68;
  font-size: 1.08em;
  line-height: 1.78;
}

h1 {
  max-width: 18ch;
  margin: 0.15rem 0 1.5rem;
  font-size: clamp(2.05rem, 4.5vw, 3.25rem);
  line-height: 1.1;
  letter-spacing: -0.035em;
}

h2 {
  margin: 2.8rem 0 0.9rem;
  padding-top: 0.15rem;
  color: var(--ink);
  font-size: clamp(1.45rem, 2.6vw, 2rem);
  line-height: 1.25;
  letter-spacing: -0.018em;
}

.article-card h2::before {
  content: "";
  display: inline-block;
  width: 0.42rem;
  height: 1.1em;
  margin-right: 0.55rem;
  vertical-align: -0.12em;
  background: linear-gradient(180deg, var(--mint), #3fa9f5);
  border-radius: 999px;
}

h3 {
  margin: 2rem 0 0.65rem;
  color: #174f6e;
  font-size: 1.22rem;
  line-height: 1.35;
}

p { margin: 0.85rem 0 1.2rem; }

.article-card p,
.article-card li { max-width: 70ch; }

.article-card ul,
.article-card ol {
  margin: 1rem 0 1.5rem;
  padding-left: 1.4rem;
}

.article-card li {
  margin: 0.45rem 0;
  padding-left: 0.2rem;
}

.article-card li::marker { color: var(--blue); font-weight: 800; }

blockquote {
  margin: 1.7rem 0;
  padding: 1.15rem 1.3rem;
  color: #174b43;
  background: var(--mint-soft);
  border: 1px solid #c9f3e8;
  border-left: 5px solid var(--mint);
  border-radius: 14px;
}

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

code {
  padding: 0.12em 0.32em;
  background: #edf5fa;
  border-radius: 0.35em;
  font-size: 0.9em;
}

.cta-action { margin-top: 1.5rem; }

.cta-action a,
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0.78rem 1.2rem;
  color: var(--white);
  background: linear-gradient(135deg, var(--blue), #119bc5);
  border-radius: 999px;
  box-shadow: 0 12px 25px rgba(8, 126, 175, 0.2);
  font-weight: 800;
  text-decoration: none;
  transition: transform 160ms ease, box-shadow 160ms ease;
}

.cta-action a:hover,
.button:hover {
  color: var(--white);
  box-shadow: 0 15px 30px rgba(8, 126, 175, 0.27);
  transform: translateY(-2px);
}

.related {
  position: sticky;
  top: 6.3rem;
  padding: 1.4rem;
  border-radius: 24px;
}

.related h2 {
  margin: 0 0 1rem;
  font-size: 1.28rem;
}

.related ul {
  margin: 0;
  padding-left: 1.15rem;
}

.related li { margin: 0.75rem 0; }
.related .button { width: 100%; text-align: center; }

.index {
  max-width: 1200px;
  margin: 2.5rem auto 4rem;
  padding: 0 1.25rem;
}

.index-hero {
  position: relative;
  overflow: hidden;
  margin-bottom: 2rem;
  padding: clamp(1.7rem, 5vw, 4rem);
  background: linear-gradient(135deg, #ffffff 5%, #ecfff9 100%);
  border-radius: 30px;
}

.index-hero::after {
  content: "AD";
  position: absolute;
  right: -1rem;
  bottom: -4.8rem;
  color: rgba(8, 126, 175, 0.055);
  font-size: 15rem;
  font-weight: 900;
  line-height: 1;
}

.index-hero > * { position: relative; z-index: 1; }
.index-hero h1 { max-width: 22ch; }
.index-hero > p:last-child { max-width: 70ch; color: var(--muted); font-size: 1.08rem; }

.eyebrow,
.article-id {
  color: var(--blue);
  font-size: 0.82rem;
  font-weight: 900;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.article-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.2rem;
}

.article-preview {
  min-width: 0;
  padding: 1.6rem;
  border-radius: 22px;
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.article-preview:hover {
  border-color: #addcf4;
  box-shadow: 0 24px 55px rgba(15, 54, 80, 0.12);
  transform: translateY(-3px);
}

.article-preview h2 {
  margin: 0.45rem 0 0.7rem;
  font-size: 1.35rem;
}

.article-preview h2 a { color: var(--ink); text-decoration: none; }
.article-preview h2 a:hover { color: var(--blue); }
.article-preview p:not(.article-id) { color: var(--muted); }
.read-more { font-weight: 800; }

footer {
  padding: 2.5rem 1rem;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.7);
  border-top: 1px solid var(--line);
  text-align: center;
}

footer p { margin: 0.35rem auto; }

@media (max-width: 900px) {
  .article-layout { grid-template-columns: minmax(0, 1fr); }
  .related { position: static; }
  .related ul { columns: 2; column-gap: 2rem; }
}

@media (max-width: 640px) {
  body { font-size: 17px; }

  .site-header {
    position: static;
    align-items: flex-start;
    flex-direction: column;
    min-height: auto;
    padding: 0.85rem 1rem;
  }

  .brand::before { width: 38px; height: 38px; border-radius: 12px; }
  .site-header nav { width: 100%; }
  .site-header nav a { padding: 0.4rem 0.55rem; }

  .article-layout,
  .index {
    width: 100%;
    max-width: 100%;
    margin-top: 1rem;
    padding: 0 0.7rem;
    overflow: hidden;
  }

  .article-card {
    width: 100%;
    max-width: 100%;
    padding: 1.35rem 1.2rem 2rem;
    border-radius: 20px;
  }

  h1 {
    max-width: 100%;
    font-size: clamp(1.9rem, 9vw, 2.45rem);
    letter-spacing: -0.025em;
  }

  h2 { margin-top: 2.25rem; font-size: 1.45rem; }
  .article-card h2::before { width: 0.32rem; margin-right: 0.38rem; }
  blockquote { margin-inline: 0; padding: 1rem; }

  .related { padding: 1.2rem; border-radius: 20px; }
  .related ul { columns: 1; }

  .index-hero {
    padding: 1.6rem 1.25rem 1.8rem;
    border-radius: 20px;
  }

  .index-hero::after { display: none; }
  .article-grid { grid-template-columns: minmax(0, 1fr); }
  .article-preview { padding: 1.35rem; border-radius: 20px; }
  .cta-action a, .button { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; transition: none !important; }
}