:root {
  --red: #b42332;
  --red-deep: #6f1723;
  --red-soft: #f6e7e7;
  --navy: #17324d;
  --navy-soft: #e8eef3;
  --brass: #b68b47;
  --ink: #18222c;
  --muted: #65717c;
  --line: #d9d7d2;
  --paper: #ffffff;
  --ivory: #ffffff;
  --white: #ffffff;
  --max: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Pretendard", "Noto Sans KR", "Malgun Gothic", sans-serif;
  border-top: 5px solid var(--red);
}
a { color: inherit; }
.skip-link { position: absolute; left: -9999px; }
.skip-link:focus { left: 16px; top: 16px; z-index: 100; padding: 10px 14px; background: var(--white); border: 2px solid var(--red); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); }

.hero {
  min-height: 590px;
  padding: 0 max(24px, calc((100% - var(--max)) / 2));
  background: var(--white);
  border-bottom: 1px solid var(--line);
}
.site-nav {
  min-height: 72px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 38px;
  border-bottom: 1px solid var(--line);
}
.brand { color: var(--navy); font-weight: 950; letter-spacing: .075em; text-decoration: none; }
.nav-links { display: flex; gap: 30px; }
.nav-links a { color: #34424e; font-size: 14px; font-weight: 750; text-decoration: none; }
.nav-links a:hover, .nav-links a:focus-visible { color: var(--red); }
.owner-link {
  padding: 10px 15px;
  border: 1px solid var(--red);
  border-radius: 3px;
  color: var(--red);
  font-size: 12px;
  font-weight: 850;
  letter-spacing: .04em;
  text-decoration: none;
}
.owner-link:hover, .owner-link:focus-visible { background: var(--red); color: var(--white); }

.hero-copy { position: relative; max-width: 1120px; padding: 112px 42% 102px 0; }
.hero-copy::after {
  content: "DATA\A AI\A CLOUD";
  white-space: pre;
  position: absolute;
  right: 0;
  top: 76px;
  width: 34%;
  padding: 34px 34px 38px;
  border-top: 7px solid var(--red);
  background: var(--navy);
  color: var(--white);
  font-size: clamp(34px, 4.3vw, 60px);
  font-weight: 950;
  line-height: .98;
  letter-spacing: -.055em;
  box-shadow: 18px 18px 0 var(--red-soft);
}
.eyebrow { margin: 0 0 16px; color: var(--red); font-size: 11px; font-weight: 900; letter-spacing: .2em; }
.hero h1 { margin: 0; color: var(--navy); font-size: clamp(54px, 7vw, 92px); line-height: .96; letter-spacing: -.07em; }
.hero-summary { max-width: 530px; margin: 25px 0 31px; color: var(--muted); line-height: 1.75; }
.hero-actions { display: flex; gap: 14px; }
.primary-action {
  display: inline-block;
  padding: 14px 20px;
  border-radius: 3px;
  background: var(--red);
  color: var(--white);
  font-weight: 850;
  text-decoration: none;
}
.primary-action:hover, .primary-action:focus-visible { background: var(--red-deep); }
.section-rail { display: none; }

.course-section { padding: 88px max(24px, calc((100% - var(--max)) / 2)); background: var(--white); border-top: 1px solid var(--line); }
.section-heading { margin-bottom: 26px; }
.course-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.course-group {
  min-width: 0;
  padding: 27px 27px 25px;
  border: 1px solid #d7d3cd;
  border-top: 5px solid var(--red);
  border-radius: 3px;
  background: var(--white);
}
.course-group:nth-child(3n+2) { border-top-color: var(--navy); }
.course-group:nth-child(3n) { border-top-color: var(--brass); }
.group-number { margin: 0 0 34px; color: var(--red); font-size: 12px; font-weight: 900; letter-spacing: .1em; }
.course-group:nth-child(3n+2) .group-number { color: var(--navy); }
.course-group:nth-child(3n) .group-number { color: #89662f; }
.course-group h3 { margin: 0 0 9px; color: var(--navy); font-size: 23px; letter-spacing: -.035em; }
.course-group > p:not(.group-number) { min-height: 44px; margin: 0 0 22px; color: var(--muted); line-height: 1.55; }
.course-group ul { margin: 0; padding: 0; list-style: none; }
.course-group li { border-top: 1px solid #e4e1dc; }
.course-group li a { display: block; padding: 11px 0; font-size: 14px; font-weight: 700; line-height: 1.45; text-decoration: none; }
.course-group li a::after { content: " →"; color: var(--red); opacity: 0; transition: opacity .15s ease; }
.course-group li a:hover, .course-group li a:focus-visible { color: var(--red); }
.course-group li a:hover::after, .course-group li a:focus-visible::after { opacity: 1; }

.career-section { padding: 76px max(24px, calc((100% - var(--max)) / 2)); background: var(--white); border-top: 1px solid var(--line); }
.career-heading { max-width: 690px; }
.career-heading h2 { margin: 5px 0 10px; color: var(--navy); font-size: clamp(34px, 4vw, 50px); letter-spacing: -.05em; }
.career-heading p:last-child { margin: 0 0 26px; color: var(--muted); line-height: 1.65; }
.career-links { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); border-top: 3px solid var(--red); border-bottom: 1px solid var(--line); }
.career-links a { min-height: 76px; padding: 18px 15px; border-right: 1px solid var(--line); color: #303b44; font-size: 14px; font-weight: 760; line-height: 1.45; text-decoration: none; }
.career-links a:last-child { border-right: 0; }
.career-links a:hover, .career-links a:focus-visible { background: var(--red-soft); color: var(--red-deep); }
.career-links span { color: var(--red); }

.insight-section { width: min(calc(100% - 48px), var(--max)); margin: auto; padding: 90px 0; display: grid; grid-template-columns: .85fr 1.7fr; gap: 76px; }
.insight-heading h2 { margin: 0 0 28px; color: var(--navy); font-size: clamp(48px, 6vw, 78px); line-height: .9; letter-spacing: -.07em; }
.insight-heading a { color: var(--red); font-weight: 850; text-decoration: none; }
.insight-list { border-bottom: 1px solid var(--line); }
.insight-list a { position: relative; display: block; padding: 23px 56px 23px 0; border-top: 1px solid var(--line); text-decoration: none; }
.insight-list a:hover strong, .insight-list a:focus-visible strong { color: var(--red); }
.insight-list span { color: var(--red); font-size: 11px; font-weight: 900; letter-spacing: .12em; }
.insight-list strong { display: block; margin-top: 7px; color: var(--navy); font-size: 20px; }
.insight-list i { position: absolute; right: 0; top: 28px; color: var(--brass); font-style: normal; font-weight: 800; }
.catalog-section[hidden] { display: none; }
footer { width: min(calc(100% - 48px), var(--max)); margin: auto; padding: 30px 0 42px; border-top: 3px solid var(--navy); display: flex; justify-content: space-between; gap: 20px; color: var(--muted); font-size: 13px; }
footer p { margin: 0; }

@media (max-width: 900px) {
  .hero-copy { padding-right: 0; }
  .hero-copy::after { display: none; }
  .course-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .career-links { grid-template-columns: repeat(2, 1fr); }
  .career-links a { border-bottom: 1px solid var(--line); }
  .insight-section { grid-template-columns: 1fr; gap: 38px; }
}
@media (max-width: 600px) {
  .site-nav { grid-template-columns: 1fr auto; gap: 14px; padding: 12px 0; }
  .nav-links { grid-column: 1 / -1; grid-row: 2; gap: 20px; }
  .hero { min-height: auto; background: var(--paper); }
  .hero-copy { padding: 72px 0 76px; }
  .hero h1 { font-size: clamp(48px, 16vw, 68px); }
  .course-grid, .career-links { grid-template-columns: 1fr; }
  .course-section, .career-section { padding-left: 14px; padding-right: 14px; }
  .career-links a { border-right: 0; }
  footer { flex-direction: column; }
}
@media print {
  .site-nav, .hero-actions, footer { display: none; }
  .hero { min-height: auto; padding: 20px 0; }
  .hero-copy { padding: 20px 0; }
  .hero-copy::after { display: none; }
  .course-section, .career-section, .insight-section { width: 100%; padding: 20px 0; background: #fff; }
  .course-grid { grid-template-columns: repeat(2, 1fr); }
  .course-group { break-inside: avoid; }
}