:root {
  --seo-red: #d25a4a;
  --seo-red-dark: #9f322b;
  --seo-ink: #100c0b;
  --seo-panel: #171110;
  --seo-line: #4a302a;
  --seo-text: #f2e4d3;
  --seo-muted: #a18d7c;
}

.seo-breadcrumb {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 18px !important;
  color: var(--seo-muted);
  font-size: 12px;
  font-weight: 700;
}

.seo-breadcrumb a { color: #c9b4a0; }
.seo-breadcrumb a:hover { color: var(--seo-text); }
.seo-breadcrumb span[aria-current="page"] { color: #e36a58; }

.seo-home-intro {
  margin-top: 72px !important;
  margin-bottom: 82px !important;
  padding: clamp(28px, 4vw, 50px);
  border: 1px solid var(--seo-line);
  border-radius: 18px;
  background:
    radial-gradient(circle at 91% 0%, rgba(210, 90, 74, .16), transparent 33%),
    linear-gradient(135deg, rgba(255, 255, 255, .025), transparent 48%),
    var(--seo-panel);
}

.seo-home-intro > header {
  display: grid;
  grid-template-columns: minmax(0, .8fr) minmax(300px, 1.2fr);
  gap: clamp(24px, 5vw, 72px);
  align-items: end;
}

.seo-home-intro h2,
.seo-explainer h2,
.seo-checklist h2 {
  margin: 7px 0 0;
  color: var(--seo-text);
  font: 900 clamp(28px, 4vw, 46px)/1.2 "Noto Sans KR", sans-serif;
  letter-spacing: -.055em;
}

.seo-home-intro > header > p,
.seo-explainer > header > p,
.seo-checklist > header > p {
  margin: 0;
  color: var(--seo-muted);
  font-size: 14px;
  line-height: 1.85;
}

.seo-topic-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin-top: 34px;
  overflow: hidden;
  border: 1px solid var(--seo-line);
  border-radius: 12px;
  background: var(--seo-line);
}

.seo-topic-grid a {
  min-height: 182px;
  padding: 24px 21px;
  background: #120d0c;
  transition: background .2s ease, transform .2s ease;
}

.seo-topic-grid a:hover,
.seo-topic-grid a:focus-visible {
  position: relative;
  z-index: 1;
  background: #211513;
  outline: 2px solid var(--seo-red);
  outline-offset: -2px;
}

.seo-topic-grid small {
  display: block;
  color: var(--seo-red);
  font: 700 10px/1.4 "IBM Plex Mono", monospace;
  letter-spacing: .13em;
}

.seo-topic-grid strong {
  display: block;
  margin-top: 19px;
  color: var(--seo-text);
  font-size: 18px;
  letter-spacing: -.035em;
}

.seo-topic-grid p {
  margin: 10px 0 0;
  color: var(--seo-muted);
  font-size: 12px;
  line-height: 1.75;
}

.seo-topic-grid b {
  display: block;
  margin-top: 17px;
  color: #e36a58;
  font-size: 13px;
}

.seo-explainer,
.seo-checklist {
  margin-top: 54px !important;
  padding: clamp(26px, 4vw, 48px);
  scroll-margin-top: 92px;
  border: 1px solid var(--seo-line);
  border-radius: 16px;
  background: var(--seo-panel);
}

.seo-explainer > header,
.seo-checklist > header {
  display: grid;
  grid-template-columns: minmax(240px, .75fr) minmax(300px, 1.25fr);
  gap: clamp(24px, 5vw, 72px);
  align-items: end;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--seo-line);
}

.seo-term-grid,
.seo-check-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 1px;
  background: var(--seo-line);
}

.seo-term-grid article,
.seo-check-grid article {
  min-height: 190px;
  padding: 27px 24px;
  background: #120d0c;
}

.seo-term-grid article[id] { scroll-margin-top: 92px; }

.seo-term-grid h3,
.seo-check-grid h3 {
  margin: 0;
  color: #ead9c6;
  font-size: 19px;
  letter-spacing: -.035em;
}

.seo-term-grid p,
.seo-check-grid p {
  margin: 11px 0 0;
  color: var(--seo-muted);
  font-size: 13px;
  line-height: 1.85;
}

.seo-term-grid a,
.seo-check-grid a {
  display: inline-flex;
  margin-top: 14px;
  color: #e36a58;
  font-size: 12px;
  font-weight: 800;
}

.seo-check-grid { grid-template-columns: repeat(5, minmax(0, 1fr)); }
.seo-check-grid article { min-height: 210px; }
.seo-check-grid span {
  display: block;
  margin-bottom: 22px;
  color: var(--seo-red);
  font: 700 11px/1 "IBM Plex Mono", monospace;
}

.guide-steps.seo-five-steps { grid-template-columns: repeat(5, minmax(0, 1fr)); }
.guide-steps.seo-five-steps li { border-bottom: 0; }
.guide-steps.seo-five-steps li:last-child { border-right: 0; }

.seo-independence-note {
  margin: 22px 0 0;
  padding: 16px 18px;
  border-left: 3px solid var(--seo-red-dark);
  background: rgba(110, 48, 41, .12);
  color: #aa9684;
  font-size: 12px;
  line-height: 1.8;
}

.seo-text-link {
  color: #e36a58;
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 3px;
}

@media (max-width: 1100px) {
  .seo-topic-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .seo-check-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .seo-check-grid article:last-child { grid-column: 1 / -1; }
  .guide-steps.seo-five-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .guide-steps.seo-five-steps li { border-right: 1px solid var(--seo-line); border-bottom: 1px solid var(--seo-line); }
  .guide-steps.seo-five-steps li:nth-child(even) { border-right: 0; }
  .guide-steps.seo-five-steps li:last-child { grid-column: 1 / -1; border-right: 0; border-bottom: 0; }
}

@media (max-width: 760px) {
  .seo-breadcrumb { margin-bottom: 12px !important; font-size: 10px; }
  .seo-home-intro { margin-top: 46px !important; margin-bottom: 52px !important; padding: 22px 18px; border-radius: 12px; }
  .seo-home-intro > header,
  .seo-explainer > header,
  .seo-checklist > header { grid-template-columns: 1fr; gap: 16px; }
  .seo-home-intro h2,
  .seo-explainer h2,
  .seo-checklist h2 { font-size: 29px; }
  .seo-home-intro > header > p,
  .seo-explainer > header > p,
  .seo-checklist > header > p { font-size: 12px; line-height: 1.75; }
  .seo-topic-grid { grid-template-columns: 1fr; margin-top: 24px; }
  .seo-topic-grid a { min-height: 0; padding: 20px 18px; }
  .seo-topic-grid strong { margin-top: 13px; font-size: 16px; }
  .seo-explainer,
  .seo-checklist { margin-top: 40px !important; padding: 22px 18px; border-radius: 12px; }
  .seo-explainer > header,
  .seo-checklist > header { padding-bottom: 22px; }
  .seo-term-grid,
  .seo-check-grid { grid-template-columns: 1fr; }
  .seo-term-grid article,
  .seo-check-grid article { min-height: 0; padding: 22px 18px; }
  .seo-check-grid article:last-child { grid-column: auto; }
  .seo-term-grid h3,
  .seo-check-grid h3 { font-size: 17px; }
  .seo-term-grid p,
  .seo-check-grid p { font-size: 12px; line-height: 1.75; }
  .guide-steps.seo-five-steps { grid-template-columns: 1fr; }
  .guide-steps.seo-five-steps li,
  .guide-steps.seo-five-steps li:nth-child(even),
  .guide-steps.seo-five-steps li:last-child { grid-column: auto; border-right: 0; border-bottom: 1px solid var(--seo-line); }
  .guide-steps.seo-five-steps li:last-child { border-bottom: 0; }
}