:root {
  --ink: #111827;
  --text: #374151;
  --muted: #6b7280;
  --line: #e5e7eb;
  --soft: #f7f8fa;
  --green: #19b565;
  --green-dark: #087548;
  --green-soft: #eaf8f0;
  --amber-soft: #fff7ed;
  --amber-line: #fed7aa;
  --shadow: 0 24px 70px rgba(17, 24, 39, 0.10);
  --shadow-soft: 0 12px 34px rgba(17, 24, 39, 0.07);
  --container: 1120px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: #fff;
  line-height: 1.72;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
}

.topbar {
  background: #0f172a;
  color: rgba(255,255,255,.86);
  font-size: .88rem;
  padding: 10px 0;
}

.topbar .container {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255,255,255,.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(18px);
}

.nav {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  font-weight: 900;
  letter-spacing: -0.02em;
}

.brand-icon {
  width: 42px;
  height: 42px;
  border-radius: 13px;
  background: var(--green-soft);
  color: var(--green-dark);
  display: grid;
  place-items: center;
  border: 1px solid rgba(8,117,72,.12);
}

.brand-icon svg {
  width: 24px;
  height: 24px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  color: var(--muted);
  font-weight: 800;
  font-size: .94rem;
}

.nav-links a:hover,
.nav-links .active {
  color: var(--green-dark);
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 12px 18px;
  border-radius: 12px;
  background: var(--green);
  color: #fff;
  font-weight: 900;
  box-shadow: 0 12px 25px rgba(25,181,101,.22);
}

.hero {
  padding: 58px 0 34px;
  background: linear-gradient(180deg, #fff 0%, #fff 74%, var(--soft) 74%, var(--soft) 100%);
}

.breadcrumb {
  color: var(--muted);
  font-weight: 800;
  font-size: .9rem;
  margin-bottom: 18px;
}

.kicker {
  display: inline-flex;
  color: var(--green-dark);
  background: var(--green-soft);
  border: 1px solid rgba(8,117,72,.14);
  border-radius: 999px;
  padding: 7px 12px;
  font-weight: 900;
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .06em;
  margin-bottom: 16px;
}

h1,
h2,
h3 {
  color: var(--ink);
  line-height: 1.12;
  letter-spacing: -0.035em;
}

h1 {
  font-size: clamp(2.35rem, 5vw, 4.25rem);
  max-width: 900px;
  margin-bottom: 18px;
}

.lead {
  max-width: 820px;
  color: var(--text);
  font-size: 1.16rem;
  margin-bottom: 26px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 330px;
  gap: 34px;
  align-items: start;
}

.article-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 330px;
  gap: 38px;
  align-items: start;
  padding: 58px 0;
}

.article {
  max-width: 780px;
}

.article h2 {
  font-size: clamp(1.65rem, 3vw, 2.25rem);
  margin: 42px 0 12px;
}

.article h3 {
  font-size: 1.22rem;
  margin: 28px 0 8px;
}

.article p,
.article li {
  color: var(--text);
  font-size: 1.02rem;
}

.article p {
  margin-bottom: 16px;
}

.article ul,
.article ol {
  padding-left: 22px;
  margin: 14px 0 20px;
}

.article li {
  margin-bottom: 9px;
}

.toc,
.note,
.warning,
.example-box,
.side-card,
.visual,
.guide-figure,
.article-card {
  border-radius: 18px;
  border: 1px solid var(--line);
  background: #fff;
  box-shadow: var(--shadow-soft);
}

.toc {
  padding: 22px;
  margin: 28px 0 34px;
}

.toc strong {
  display: block;
  color: var(--ink);
  margin-bottom: 10px;
}

.toc ol {
  margin: 0;
}

.toc a {
  color: var(--green-dark);
  font-weight: 800;
}

.note {
  padding: 20px;
  background: var(--green-soft);
  border-color: rgba(8,117,72,.16);
  color: var(--green-dark);
  font-weight: 700;
  margin: 24px 0;
}

.warning {
  padding: 20px;
  background: var(--amber-soft);
  border-color: var(--amber-line);
  color: #9a3412;
  font-weight: 700;
  margin: 24px 0;
}

.example-box {
  padding: 22px;
  margin: 24px 0;
}

.example-box strong {
  display: block;
  color: var(--ink);
  margin-bottom: 8px;
}

.side-card {
  position: sticky;
  top: 104px;
  padding: 24px;
}

.side-card .price {
  display: block;
  color: var(--green-dark);
  font-size: 2.65rem;
  font-weight: 900;
  letter-spacing: -0.05em;
  line-height: 1;
  margin: 12px 0;
}

.side-card h2 {
  font-size: 1.35rem;
  margin-bottom: 8px;
}

.side-card p {
  color: var(--muted);
  font-weight: 700;
  margin-bottom: 16px;
}

.btn {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  min-height: 48px;
  padding: 13px 18px;
  border-radius: 12px;
  background: var(--green);
  color: #fff;
  font-weight: 900;
  margin-top: 10px;
}

.btn.secondary {
  background: #fff;
  color: var(--green-dark);
  border: 1px solid var(--line);
}

.mini-list {
  display: grid;
  gap: 10px;
  margin: 18px 0;
}

.mini-list span {
  display: grid;
  grid-template-columns: 24px 1fr;
  gap: 10px;
  color: var(--text);
  font-weight: 800;
}

.mini-list span::before {
  content: "✓";
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--green-soft);
  color: var(--green-dark);
  display: grid;
  place-items: center;
  font-size: .82rem;
}

.visual {
  padding: 24px;
  min-height: 260px;
  display: grid;
  align-content: center;
  gap: 16px;
}

.visual-flow {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  align-items: stretch;
}

.visual-step {
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 16px;
  min-height: 120px;
}

.visual-step strong {
  display: block;
  color: var(--ink);
  margin-bottom: 6px;
}

.visual-step span {
  color: var(--muted);
  font-weight: 700;
  font-size: .92rem;
}

.guide-figure {
  overflow: hidden;
  margin: 0 0 34px;
}

.guide-figure img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: var(--soft);
}

.guide-figure figcaption {
  padding: 14px 18px;
  color: var(--muted);
  font-weight: 800;
  font-size: .92rem;
  border-top: 1px solid var(--line);
}

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

.article-card {
  overflow: hidden;
}

.article-card img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: var(--soft);
  border-bottom: 1px solid var(--line);
}

.article-card-body {
  padding: 22px;
}

.article-card h2 {
  font-size: 1.25rem;
  margin-bottom: 8px;
}

.article-card p {
  color: var(--muted);
  font-weight: 700;
  margin-bottom: 16px;
}

.article-card a {
  color: var(--green-dark);
  font-weight: 900;
}

.faq {
  display: grid;
  gap: 12px;
  margin-top: 18px;
}

details {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: var(--shadow-soft);
}

summary {
  cursor: pointer;
  list-style: none;
  padding: 18px 20px;
  color: var(--ink);
  font-weight: 900;
}

summary::-webkit-details-marker {
  display: none;
}

details p {
  padding: 0 20px 18px;
  color: var(--muted);
  font-weight: 700;
}

.cta-band {
  background: #111827;
  color: rgba(255,255,255,.82);
  padding: 58px 0;
}

.cta-band h2 {
  color: #fff;
  font-size: clamp(1.9rem, 4vw, 3rem);
  margin-bottom: 10px;
}

.cta-grid {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 30px;
  align-items: center;
}

.footer {
  background: #fff;
  border-top: 1px solid var(--line);
  padding: 28px 0;
  color: var(--muted);
  font-size: .92rem;
}

.footer .container {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.footer a {
  color: var(--ink);
  font-weight: 800;
}

@media (max-width: 940px) {
  .hero-grid,
  .article-shell,
  .cta-grid {
    grid-template-columns: 1fr;
  }

  .side-card {
    position: static;
  }

  .visual-flow,
  .cards-grid {
    grid-template-columns: 1fr 1fr;
  }

  .nav-links {
    display: none;
  }
}

@media (max-width: 640px) {
  .topbar {
    display: none;
  }

  .nav-cta {
    display: none;
  }

  .hero {
    padding-top: 38px;
  }

  .visual-flow,
  .cards-grid {
    grid-template-columns: 1fr;
  }
}