:root {
  color-scheme: light;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans KR", sans-serif;
  color: #172033;
  background: #f6f8fb;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  --background: #f6f8fb;
  --surface: #ffffff;
  --surface-soft: #eef4fb;
  --text: #172033;
  --muted: #56647a;
  --line: #dbe2ec;
  --line-strong: #c7d2e0;
  --accent: #075fc9;
  --accent-strong: #004da8;
  --accent-soft: #e9f2ff;
  --shadow: 0 18px 50px rgba(32, 54, 86, 0.09);
  --radius-lg: 24px;
  --radius-md: 16px;
  --content: 70rem;
  --reading: 44rem;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 84% 3%, rgba(40, 115, 230, 0.08), transparent 24rem),
    var(--background);
  color: var(--text);
  font-size: 1rem;
  line-height: 1.7;
  overflow-wrap: break-word;
}

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

a {
  color: var(--accent);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--accent-strong);
}

a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible {
  outline: 3px solid #f0a000;
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  z-index: 100;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.7rem 1rem;
  border-radius: 0.75rem;
  background: var(--text);
  color: #ffffff;
  font-weight: 700;
  transform: translateY(-180%);
}

.skip-link:focus {
  color: #ffffff;
  transform: translateY(0);
}

.container {
  width: min(var(--content), calc(100% - 2rem));
  margin-inline: auto;
}

.site-header {
  padding-block: 1rem;
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 3rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  min-height: 2.75rem;
  color: var(--text);
  font-size: 1.04rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.brand:hover {
  color: var(--text);
}

.language-switcher {
  display: inline-flex;
  align-items: center;
  gap: 0.2rem;
  padding: 0.2rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.82);
}

.language-switcher a,
.language-switcher span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 3.25rem;
  min-height: 2.5rem;
  padding-inline: 0.75rem;
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.88rem;
  font-weight: 700;
  text-decoration: none;
}

.language-switcher [aria-current="page"] {
  background: var(--text);
  color: #ffffff;
}

main {
  display: block;
}

.hero {
  padding-block: clamp(4rem, 12vw, 8rem) clamp(3.5rem, 9vw, 6.5rem);
}

.hero__content {
  max-width: 47rem;
}

.eyebrow {
  margin: 0 0 0.75rem;
  color: var(--accent-strong);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.08em;
}

h1,
h2,
h3 {
  margin-top: 0;
  color: var(--text);
  line-height: 1.25;
  letter-spacing: -0.035em;
}

h1 {
  max-width: 15ch;
  margin-bottom: 1.25rem;
  font-size: clamp(2.4rem, 9vw, 5.2rem);
  font-weight: 800;
  line-height: 1.08;
}

h2 {
  margin-bottom: 0.8rem;
  font-size: clamp(1.55rem, 5vw, 2.2rem);
}

h3 {
  margin-bottom: 0.5rem;
  font-size: 1.15rem;
}

p,
li {
  color: var(--muted);
}

.lead {
  max-width: 40rem;
  margin: 0;
  font-size: clamp(1.05rem, 3vw, 1.3rem);
  line-height: 1.7;
}

.section {
  padding-block: 2rem clamp(4.5rem, 10vw, 7rem);
}

.section-heading {
  max-width: 40rem;
  margin-bottom: 1.75rem;
}

.section-heading p {
  margin: 0;
}

.app-card {
  position: relative;
  display: grid;
  gap: 1.5rem;
  padding: clamp(1.35rem, 5vw, 2.5rem);
  overflow: hidden;
  border: 1px solid rgba(183, 197, 215, 0.8);
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.94);
  box-shadow: var(--shadow);
}

.app-card::after {
  position: absolute;
  right: -5rem;
  bottom: -7rem;
  width: 15rem;
  height: 15rem;
  border-radius: 50%;
  background: rgba(36, 104, 226, 0.07);
  content: "";
  pointer-events: none;
}

.app-card__icon {
  width: 5.5rem;
  height: 5.5rem;
  border: 1px solid rgba(176, 191, 210, 0.72);
  border-radius: 1.35rem;
  box-shadow: 0 12px 28px rgba(29, 66, 120, 0.15);
}

.app-card__body {
  position: relative;
  z-index: 1;
}

.app-card__body h3 {
  margin-bottom: 0.65rem;
  font-size: clamp(1.65rem, 6vw, 2.35rem);
}

.app-card__body p {
  max-width: 36rem;
  margin: 0;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.9rem;
  padding: 0.68rem 1rem;
  border: 1px solid var(--line-strong);
  border-radius: 0.8rem;
  background: var(--surface);
  color: var(--text);
  font-weight: 750;
  line-height: 1.3;
  text-decoration: none;
}

.button:hover {
  border-color: var(--accent);
  color: var(--accent-strong);
  background: var(--accent-soft);
}

.button--primary {
  border-color: var(--accent);
  background: var(--accent);
  color: #ffffff;
}

.button--primary:hover {
  border-color: var(--accent-strong);
  background: var(--accent-strong);
  color: #ffffff;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem 0.55rem;
  margin: 0;
  padding: 1.25rem 0 0;
  list-style: none;
}

.breadcrumb li {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--muted);
  font-size: 0.88rem;
}

.breadcrumb li:not(:last-child)::after {
  color: #8a97a9;
  content: "/";
}

.breadcrumb a {
  color: var(--muted);
}

.page-hero {
  padding-block: clamp(2.75rem, 8vw, 5rem) clamp(2.5rem, 7vw, 4.5rem);
}

.page-hero h1 {
  max-width: 18ch;
  font-size: clamp(2.25rem, 8vw, 4.25rem);
}

.page-hero .lead {
  max-width: 43rem;
}

.page-hero__app {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.page-hero__app .app-card__icon {
  flex: 0 0 auto;
  width: 4rem;
  height: 4rem;
  border-radius: 1rem;
}

.page-hero__app p {
  margin: 0;
  color: var(--text);
  font-size: 1.05rem;
  font-weight: 800;
}

.meta {
  margin: 0 0 1rem;
  color: var(--muted);
  font-size: 0.92rem;
}

.content-section {
  padding-block: 0 clamp(4.5rem, 10vw, 7rem);
}

.info-grid {
  display: grid;
  gap: 1rem;
}

.info-card {
  padding: 1.35rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.88);
}

.info-card h2,
.info-card h3 {
  margin-bottom: 0.55rem;
}

.info-card p {
  margin: 0;
}

.contact-card {
  padding: clamp(1.5rem, 5vw, 2.5rem);
  border: 1px solid #b9cbe2;
  border-radius: var(--radius-lg);
  background: linear-gradient(145deg, #ffffff, #eef5ff);
  box-shadow: var(--shadow);
}

.contact-card h2 {
  margin-bottom: 0.75rem;
}

.contact-card p {
  max-width: 40rem;
}

.contact-address {
  display: inline-flex;
  align-items: center;
  min-height: 3rem;
  margin-block: 0.35rem 0.75rem;
  color: var(--accent-strong);
  font-size: clamp(1.05rem, 4.5vw, 1.35rem);
  font-weight: 800;
}

.checklist {
  margin: 1.4rem 0 0;
  padding: 1.2rem 1.2rem 1.2rem 2.5rem;
  border-radius: var(--radius-md);
  background: var(--surface-soft);
}

.checklist li + li {
  margin-top: 0.45rem;
}

.notice {
  margin-top: 1.5rem;
  padding: 1rem 1.1rem;
  border-left: 4px solid var(--accent);
  border-radius: 0 0.75rem 0.75rem 0;
  background: var(--accent-soft);
}

.notice p {
  margin: 0;
  color: #34445c;
}

.content-grid {
  display: grid;
  gap: 2.5rem;
}

.toc {
  padding: 1.1rem 1.2rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.84);
}

.toc h2 {
  margin-bottom: 0.75rem;
  font-size: 1rem;
  letter-spacing: -0.01em;
}

.toc ol {
  display: grid;
  gap: 0.4rem;
  margin: 0;
  padding-left: 1.3rem;
}

.toc a {
  color: var(--muted);
  font-size: 0.92rem;
}

.prose {
  max-width: var(--reading);
}

.prose section {
  scroll-margin-top: 1.5rem;
}

.prose section + section {
  margin-top: 3.25rem;
  padding-top: 3.25rem;
  border-top: 1px solid var(--line);
}

.prose h2 {
  margin-bottom: 1rem;
  font-size: clamp(1.4rem, 5vw, 1.85rem);
}

.prose h3 {
  margin-top: 1.6rem;
}

.prose p,
.prose ul {
  margin-top: 0;
  margin-bottom: 1rem;
}

.prose li + li {
  margin-top: 0.45rem;
}

.prose strong {
  color: var(--text);
}

.link-list {
  display: grid;
  gap: 0.75rem;
  margin: 1.4rem 0 0;
  padding: 0;
  list-style: none;
}

.link-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 3.5rem;
  padding: 0.75rem 1rem;
  border: 1px solid var(--line);
  border-radius: 0.85rem;
  background: var(--surface);
  color: var(--text);
  font-weight: 700;
  text-decoration: none;
}

.link-list a::after {
  color: var(--accent);
  content: "→";
}

.link-list a:hover {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.error-layout {
  display: grid;
  place-items: center;
  min-height: calc(100vh - 11rem);
  padding-block: 4rem;
}

.error-card {
  width: min(38rem, 100%);
  padding: clamp(1.5rem, 7vw, 3rem);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.error-code {
  margin: 0 0 0.5rem;
  color: var(--accent);
  font-size: 0.92rem;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.error-card h1 {
  font-size: clamp(2rem, 8vw, 3.4rem);
}

.site-footer {
  border-top: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.48);
}

.site-footer__inner {
  display: grid;
  gap: 1.25rem;
  padding-block: 2rem 2.5rem;
}

.site-footer p {
  margin: 0;
  font-size: 0.9rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.1rem;
}

.footer-links a {
  display: inline-flex;
  align-items: center;
  min-height: 2.75rem;
  color: var(--muted);
  font-size: 0.9rem;
}

@media (min-width: 44rem) {
  .container {
    width: min(var(--content), calc(100% - 4rem));
  }

  .site-header {
    padding-block: 1.4rem;
  }

  .app-card {
    grid-template-columns: auto 1fr;
    align-items: center;
    gap: 2.25rem;
  }

  .app-card__icon {
    width: 7.5rem;
    height: 7.5rem;
    border-radius: 1.8rem;
  }

  .site-footer__inner {
    grid-template-columns: 1fr auto;
    align-items: center;
  }

  .info-grid {
    grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr));
  }
}

@media (min-width: 60rem) {
  .content-grid {
    grid-template-columns: 13rem minmax(0, var(--reading));
    justify-content: center;
    gap: 4rem;
  }

  .toc {
    position: sticky;
    top: 1.5rem;
    align-self: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}