:root {
  --bg: #f8f9fb;
  --surface: #ffffff;
  --surface-alt: #f1f5f9;
  --text-primary: #1b2430;
  --text-secondary: #475569;
  --brand: #0051ad;
  --brand-strong: #003e85;
  --border: #dce4ec;
  --shadow: 0 10px 25px rgba(15, 23, 42, 0.08);
}

:root[data-theme="dark"] {
  --bg: #111827;
  --surface: #1f2937;
  --surface-alt: #273447;
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --brand: #60a5fa;
  --brand-strong: #93c5fd;
  --border: #334155;
  --shadow: 0 10px 25px rgba(2, 6, 23, 0.55);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  font-family: "Noto Sans KR", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.6;
}

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

.container {
  width: min(1120px, 100%);
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  padding: 0.8rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.site-logo {
  width: auto;
  height: 36px;
  max-width: 100%;
}

.header-links {
  display: flex;
  align-items: center;
  gap: 0.55rem;
}

.quick-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface-alt);
  color: var(--text-secondary);
  font-size: 0.88rem;
  font-weight: 700;
  white-space: nowrap;
}

.quick-link:hover {
  border-color: var(--brand);
  color: var(--brand);
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  color: var(--text-secondary);
  font-size: 0.88rem;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
  transition: border-color 0.15s ease, color 0.15s ease, background 0.15s ease;
}

.theme-toggle:hover {
  border-color: var(--brand);
  color: var(--brand);
  background: var(--surface-alt);
}

.theme-toggle:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
}

main {
  min-height: calc(100vh - 230px);
}

.hero-section {
  padding: 3.4rem 1rem 2.1rem;
  background: linear-gradient(150deg, var(--surface) 0%, var(--surface-alt) 100%);
}

.theme-badge {
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  border: 1px solid var(--border);
  padding: 0.45rem 0.75rem;
  background: var(--surface-alt);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.95rem;
}

h1 {
  margin: 0;
  font-size: clamp(1.9rem, 3vw + 1rem, 3rem);
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.accent {
  color: var(--brand);
}

.lead {
  margin-top: 1rem;
  margin-bottom: 0;
  color: var(--text-secondary);
  font-size: 1.04rem;
}

.page-frame {
  padding: 0 1rem 3rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 1rem;
  box-shadow: var(--shadow);
  padding: 1.4rem;
}

.text-center {
  text-align: center;
}

.notice {
  margin: 0;
  border-radius: 0.8rem;
  padding: 0.8rem 0.9rem;
  font-size: 0.95rem;
  font-weight: 500;
}

.notice + .notice {
  margin-top: 0.65rem;
}

.notice.danger {
  background: #fff1f2;
  color: #be123c;
  border: 1px solid #fecdd3;
}

.notice.info {
  background: #eff6ff;
  color: #1d4ed8;
  border: 1px solid #bfdbfe;
}

:root[data-theme="dark"] .notice.danger {
  background: rgba(190, 24, 93, 0.16);
  color: #fda4af;
  border-color: rgba(251, 113, 133, 0.4);
}

:root[data-theme="dark"] .notice.info {
  background: rgba(29, 78, 216, 0.18);
  color: #bfdbfe;
  border-color: rgba(96, 165, 250, 0.42);
}

.subheading {
  margin: 1.15rem 0 0.4rem;
  font-size: 1.02rem;
  font-weight: 800;
  color: var(--text-primary);
}

.support-list {
  margin: 0;
  padding-left: 1rem;
  color: var(--text-secondary);
  font-size: 0.93rem;
}

.iframe-wrap {
  margin-top: 1rem;
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  overflow: hidden;
  padding: 0.5rem;
  background: linear-gradient(180deg, #f8fbff, #eef4ff);
}

:root[data-theme="dark"] .iframe-wrap {
  background: linear-gradient(180deg, rgba(37, 99, 235, 0.18), rgba(15, 23, 42, 0.55));
  border-color: rgba(96, 165, 250, 0.35);
}

.iframe-wrap iframe {
  width: 100%;
  min-height: 340px;
  border: 0;
  border-radius: 0.6rem;
  background: #ffffff;
  display: block;
}

:root[data-theme="dark"] .iframe-wrap iframe {
  background: #0f172a;
}

.selection-guide {
  margin-top: 1rem;
  margin-bottom: 1rem;
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  background: #f8fbff;
  padding: 1rem;
}

:root[data-theme="dark"] .selection-guide {
  background: rgba(37, 99, 235, 0.12);
  border-color: rgba(96, 165, 250, 0.3);
}

.selection-guide p {
  margin: 0.35rem 0 0.55rem;
  font-size: 0.93rem;
  color: var(--text-secondary);
}

.choice-list {
  margin: 0;
  padding-left: 1rem;
}

.choice-list li {
  margin-bottom: 0.4rem;
  color: var(--text-secondary);
  font-size: 0.93rem;
}

.form-grid {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.form-block {
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  background: #eef4ff;
  overflow: hidden;
  padding: 0.5rem;
}

:root[data-theme="dark"] .form-block {
  background: rgba(30, 58, 138, 0.22);
  border-color: rgba(96, 165, 250, 0.35);
}

.form-block h3 {
  margin: 0;
  padding: 0.85rem 1rem;
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--brand);
  border-bottom: 1px solid var(--border);
  background: #f8fbff;
}

:root[data-theme="dark"] .form-block h3 {
  background: rgba(37, 99, 235, 0.14);
}

.form-block iframe {
  width: 100%;
  min-height: 340px;
  border: 0;
  border-radius: 0.6rem;
  background: #ffffff;
  display: block;
}

:root[data-theme="dark"] .form-block iframe {
  background: #0f172a;
}

.preview {
  display: block;
  width: min(100%, 460px);
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  margin: 1.3rem auto 1rem;
  box-shadow: var(--shadow);
}

.primary-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.2rem;
  border-radius: 0.7rem;
  background: var(--brand);
  color: #ffffff;
  font-weight: 700;
  border: 1px solid var(--brand);
}

.primary-btn:hover {
  background: var(--brand-strong);
  border-color: var(--brand-strong);
}

.file-meta {
  margin: 0.9rem auto 1.2rem;
  width: min(520px, 100%);
  text-align: left;
  border: 1px solid var(--border);
  border-radius: 0.8rem;
  background: #fbfdff;
  padding: 0.85rem 0.95rem;
}

:root[data-theme="dark"] .file-meta {
  background: rgba(15, 23, 42, 0.45);
}

.file-meta p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.92rem;
}

.file-meta p + p {
  margin-top: 0.35rem;
}

.site-footer {
  background: #0b1220;
  color: #e2e8f0;
  padding: 2.4rem 1rem;
}

.footer-inner {
  max-width: 1120px;
  margin: 0 auto;
}

.footer-title {
  margin: 0 0 0.75rem;
  font-size: 1.1rem;
  font-weight: 700;
  color: #ffffff;
}

.footer-contact-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  margin: 0 0 1rem;
}

.footer-contact-card {
  background: rgba(30, 41, 59, 0.7);
  border: 1px solid rgba(148, 163, 184, 0.35);
  border-radius: 0.85rem;
  padding: 0.85rem 0.95rem;
}

.footer-contact-role {
  margin: 0 0 0.25rem;
  font-size: 0.83rem;
  color: #93c5fd;
  font-weight: 700;
}

:root[data-theme="dark"] .footer-contact-role {
  color: #bfdbfe;
}

.footer-contact-name {
  margin: 0;
  font-size: 1rem;
  color: #f8fafc;
  font-weight: 700;
  line-height: 1.45;
}

.footer-contact-email {
  margin: 0.3rem 0 0;
  color: #cbd5e1;
  font-size: 0.92rem;
}

.footer-contact-email a {
  color: #bfdbfe;
  text-decoration: underline;
  text-underline-offset: 2px;
}

:root[data-theme="dark"] .footer-contact-email a {
  color: #dbeafe;
}

.footer-copy {
  margin: 0;
  line-height: 1.8;
  font-size: 0.95rem;
}

@media (max-width: 900px) {
  .footer-contact-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .site-logo {
    height: 30px;
  }

  .header-inner {
    flex-wrap: wrap;
  }

  .header-links {
    width: 100%;
  }

  .quick-link {
    flex: 1 1 auto;
    min-width: 0;
    font-size: 0.8rem;
    padding: 0.45rem 0.72rem;
  }

  .theme-toggle {
    flex: 1 1 auto;
    min-width: 0;
    font-size: 0.8rem;
    padding: 0.45rem 0.72rem;
  }

  .hero-section {
    padding: 2.4rem 1rem 1.7rem;
  }

  .iframe-wrap iframe,
  .form-block iframe {
    min-height: 420px;
  }

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