:root {
  color-scheme: light;
  --ink: #18212f;
  --muted: #5e6a7d;
  --line: #d9e0ea;
  --panel: #ffffff;
  --paper: #f5f7fb;
  --accent: #0f8f83;
  --accent-dark: #0a655f;
  --warm: #f2b84b;
}

* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
  background: var(--paper);
}

body {
  margin: 0;
  color: var(--ink);
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.5;
}

a {
  color: inherit;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 72px;
  padding: 14px clamp(18px, 5vw, 64px);
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.94);
  position: sticky;
  top: 0;
  z-index: 5;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 8px;
  background: var(--ink);
  color: white;
  font-size: 14px;
}

nav {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

nav a {
  padding: 9px 12px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
}

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

.button:hover {
  background: var(--accent-dark);
}

.topbar nav a:not(.button):hover {
  color: var(--accent-dark);
}

main {
  width: min(1180px, calc(100% - 36px));
  margin: 0 auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 28px;
  align-items: end;
  padding: 58px 0 32px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent-dark);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

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

h1 {
  max-width: 780px;
  margin-bottom: 14px;
  font-size: clamp(42px, 8vw, 78px);
  line-height: 0.98;
  letter-spacing: 0;
}

.lede {
  max-width: 760px;
  margin-bottom: 0;
  color: var(--muted);
  font-size: clamp(17px, 2vw, 21px);
}

.stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(92px, 1fr));
  gap: 10px;
  min-width: min(100%, 340px);
}

.stats div {
  padding: 14px;
  border: 1px solid var(--line);
  border-top: 5px solid var(--warm);
  border-radius: 8px;
  background: var(--panel);
}

.stats strong,
.stats span {
  display: block;
}

.stats strong {
  font-size: 24px;
}

.stats span {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

.addition {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin: 0 0 26px;
  padding: 22px;
  border: 1px solid var(--line);
  border-left: 6px solid var(--accent);
  border-radius: 8px;
  background: var(--panel);
}

.addition h2,
.addition p {
  margin-bottom: 0;
}

.addition h2 {
  margin-top: -4px;
  font-size: 28px;
  line-height: 1.1;
}

.addition p:not(.eyebrow) {
  max-width: 760px;
  margin-top: 8px;
  color: var(--muted);
}

.viewer-section {
  margin: 0 0 34px;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  background: var(--panel);
}

.viewer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
}

.viewer-header h2 {
  margin: 0;
  font-size: 18px;
}

.viewer-header a {
  color: var(--accent-dark);
  font-size: 14px;
  font-weight: 800;
  text-decoration: none;
}

.pdf-viewer {
  display: block;
  width: 100%;
  height: min(78vh, 900px);
  min-height: 560px;
  border: 0;
  background: #eef2f7;
}

.article-shell {
  max-width: 1040px;
}

.article-hero {
  padding: 54px 0 28px;
}

.article-hero h1 {
  max-width: 920px;
  font-size: clamp(38px, 6vw, 68px);
}

.content-block {
  padding: 30px 0;
  border-top: 1px solid var(--line);
}

.content-block h2 {
  margin-bottom: 12px;
  font-size: clamp(24px, 3vw, 34px);
  line-height: 1.15;
}

.content-block h3 {
  margin: 0 0 10px;
  font-size: 18px;
  line-height: 1.2;
}

.content-block p {
  max-width: 860px;
  color: var(--muted);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.mini-card {
  min-width: 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.mini-card ul,
.plain-list {
  margin: 0;
  padding-left: 19px;
  color: var(--muted);
}

.mini-card li,
.plain-list li {
  margin: 6px 0;
}

.check-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin: 18px 0;
}

.check-grid span {
  display: flex;
  align-items: center;
  min-height: 48px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--ink);
  font-size: 14px;
  font-weight: 700;
}

.fake-form {
  display: grid;
  gap: 10px;
  max-width: 620px;
  margin: 18px 0;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.fake-form p {
  margin-bottom: 4px;
}

.fake-form label {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  color: var(--muted);
  font-weight: 700;
}

.fake-form input {
  width: 18px;
  height: 18px;
  margin-top: 2px;
}

.prompt-block,
.code-block {
  overflow-x: auto;
  max-width: 100%;
  margin: 18px 0 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #111827;
  color: #f8fafc;
  font-size: 14px;
  line-height: 1.55;
  white-space: pre-wrap;
}

.callout {
  max-width: 760px;
  margin: 18px 0 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-left: 5px solid var(--warm);
  border-radius: 8px;
  background: var(--panel);
}

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

.callout ol {
  padding-left: 22px;
  color: var(--muted);
}

.final-rule {
  padding-bottom: 54px;
}

@media (max-width: 820px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
  }

  nav {
    width: 100%;
    justify-content: flex-start;
  }

  .hero {
    grid-template-columns: 1fr;
    padding-top: 38px;
  }

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

  .feature-grid,
  .check-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  main {
    width: min(100% - 28px, 1180px);
  }

  h1 {
    font-size: 40px;
  }

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

  .viewer-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .pdf-viewer {
    min-height: 500px;
  }
}