/* CSOS homepage - plain CSS, no external resources */
:root {
  --navy: #0c1f3d;
  --navy-2: #173a6b;
  --navy-3: #22508f;
  --accent: #e04a3f;
  --accent-dark: #b8322a;
  --violet: #7b56c9;
  --ink: #1b2430;
  --muted: #5b6677;
  --line: #e2e6ee;
  --soft: #f4f6fa;
  --soft-2: #eef2f8;
  --white: #ffffff;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(12, 31, 61, .10);
  --header-h: 76px;
  --font: "Pretendard", "Noto Sans KR", "Noto Sans CJK KR", "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
  background: var(--white);
  word-break: keep-all;
  overflow-wrap: break-word;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--navy-3); text-decoration: none; }
a:hover { text-decoration: underline; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; border-radius: 4px; }
.sr { position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.skip { position: absolute; left: 12px; top: -60px; z-index: 200; background: var(--accent); color: #fff; padding: 10px 16px; border-radius: 8px; font-weight: 700; }
.skip:focus { top: 12px; }
.wrap { width: 100%; max-width: 1240px; margin: 0 auto; padding-left: 24px; padding-right: 24px; }
main:focus { outline: none; }

/* ---------------- header ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, .97);
  border-bottom: 1px solid var(--line);
  transition: box-shadow .2s;
}
.site-header.is-scrolled { box-shadow: 0 4px 18px rgba(12, 31, 61, .10); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: var(--header-h); gap: 24px; }
.brand { display: flex; align-items: center; gap: 12px; color: var(--navy); text-decoration: none !important; flex-shrink: 0; }
.brand img { height: 52px; width: auto; }
.brand-text { display: flex; flex-direction: column; line-height: 1.2; }
.brand-ko { font-size: 17px; color: var(--ink); font-weight: 700; }

.site-nav .nav-list { list-style: none; display: flex; margin: 0; padding: 0; gap: 4px; }
.nav-item { position: relative; }
.nav-top {
  display: block; padding: 0 22px; line-height: var(--header-h);
  font-weight: 700; font-size: 17px; color: var(--ink); text-decoration: none !important;
  position: relative;
}
.nav-top::after {
  content: ""; position: absolute; left: 22px; right: 22px; bottom: 18px; height: 3px;
  background: var(--accent); transform: scaleX(0); transition: transform .2s; border-radius: 2px;
}
.nav-item:hover .nav-top::after, .nav-item:focus-within .nav-top::after, .nav-top[aria-current="page"]::after { transform: scaleX(1); }
.nav-top[aria-current="page"] { color: var(--navy-3); }
.dropdown {
  list-style: none; margin: 0; padding: 10px 0;
  position: absolute; left: 50%; top: calc(var(--header-h) - 4px);
  min-width: 210px; transform: translate(-50%, 6px);
  background: var(--white); border: 1px solid var(--line); border-top: 3px solid var(--navy);
  border-radius: 0 0 10px 10px; box-shadow: var(--shadow);
  opacity: 0; visibility: hidden; transition: opacity .15s, transform .15s, visibility .15s;
}
.nav-item:hover .dropdown, .nav-item:focus-within .dropdown { opacity: 1; visibility: visible; transform: translate(-50%, 0); }
.dropdown a { display: block; padding: 8px 20px; color: var(--ink); font-size: 15px; white-space: nowrap; }
.dropdown a:hover, .dropdown a:focus-visible { background: var(--soft); color: var(--navy-3); text-decoration: none; }

.nav-toggle {
  display: none; width: 46px; height: 46px; border: 1px solid var(--line); border-radius: 10px;
  background: var(--white); cursor: pointer; padding: 11px 10px; flex-direction: column; justify-content: space-between;
}
.nav-toggle .bar { display: block; height: 3px; background: var(--navy); border-radius: 2px; transition: transform .2s, opacity .2s; }
.nav-toggle[aria-expanded="true"] .bar:nth-child(1) { transform: translateY(8.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .bar:nth-child(3) { transform: translateY(-8.5px) rotate(-45deg); }

/* ---------------- buttons, labels ---------------- */
.btn {
  display: inline-block; padding: 12px 26px; border-radius: 999px; font-weight: 700;
  background: var(--accent); color: #fff; text-decoration: none !important; transition: background .15s;
}
.btn:hover { background: var(--accent-dark); }
.btn-dark { background: var(--navy); }
.btn-dark:hover { background: var(--navy-2); }
.eyebrow { margin: 0 0 6px; font-size: 13px; font-weight: 800; letter-spacing: .16em; color: var(--accent); }
.link-more { font-weight: 700; color: var(--navy-3); white-space: nowrap; }
.link-more::after { content: " \2192"; }

/* ---------------- hero ---------------- */
.hero {
  position: relative; color: #fff; overflow: hidden;
  background:
    radial-gradient(circle at 85% 20%, rgba(123, 86, 201, .35), transparent 45%),
    radial-gradient(circle at 10% 90%, rgba(224, 74, 63, .22), transparent 40%),
    linear-gradient(120deg, var(--navy) 0%, var(--navy-2) 60%, var(--navy-3) 100%);
}
.slides { position: relative; min-height: 560px; }
.slide { position: absolute; inset: 0; opacity: 0; visibility: hidden; transition: opacity .7s, visibility .7s; }
.slide.is-active { position: relative; opacity: 1; visibility: visible; }
.slide-inner { display: grid; grid-template-columns: 1fr 1.05fr; gap: 56px; align-items: center; min-height: 560px; padding-top: 56px; padding-bottom: 88px; }
.kicker { margin: 0 0 14px; font-size: 14px; font-weight: 700; letter-spacing: .08em; color: #ffb3ad; }
.home .slide-head { color: #fff; margin: 0 0 18px; font-size: 38px; line-height: 1.3; font-weight: 800; letter-spacing: -.01em; }
.slide-desc { margin: 0 0 30px; font-size: 18px; line-height: 1.75; color: rgba(255, 255, 255, .88); }
.slide-media {
  background: #fff; border-radius: 18px; padding: 14px; box-shadow: 0 24px 60px rgba(0, 0, 0, .35);
  display: flex; align-items: center; justify-content: center;
}
.slide-media img { max-height: 380px; width: auto; object-fit: contain; border-radius: 8px; }
.hero-controls { position: absolute; left: 0; right: 0; bottom: 28px; display: flex; align-items: center; gap: 12px; }
.hero-controls button {
  border: 1px solid rgba(255, 255, 255, .5); background: rgba(255, 255, 255, .08); color: #fff; cursor: pointer;
  width: 38px; height: 38px; border-radius: 50%; font-size: 20px; line-height: 1;
}
.hero-controls .hero-pause { font-size: 11px; letter-spacing: -2px; }
.hero-controls button:hover { background: rgba(255, 255, 255, .2); }
.dots { display: flex; gap: 8px; }
.hero-controls .dot { width: 34px; height: 6px; border-radius: 3px; padding: 0; border: 0; background: rgba(255, 255, 255, .35); }
.hero-controls .dot.is-active { background: #fff; }

/* ---------------- home sections ---------------- */
.home section:not(.hero) { padding: 88px 0; }
.home h2 { margin: 0; font-size: 32px; line-height: 1.35; color: var(--navy); font-weight: 800; }
.sec-head { display: flex; justify-content: space-between; align-items: flex-end; gap: 24px; margin-bottom: 18px; }
.sec-lead { margin: 0 0 36px; color: var(--muted); font-size: 17px; max-width: 860px; }

.home-intro { background: var(--white); }
.intro-grid { display: grid; grid-template-columns: 1fr 1.4fr; gap: 56px; align-items: start; }
.intro-grid h2 { font-size: 28px; margin-bottom: 18px; }
.check-list { list-style: none; margin: 0; padding: 0; }
.check-list li { position: relative; padding: 0 0 14px 30px; margin-bottom: 14px; border-bottom: 1px solid var(--line); }
.check-list li:last-child { border-bottom: 0; margin-bottom: 0; }
.check-list li::before {
  content: ""; position: absolute; left: 4px; top: 10px; width: 10px; height: 10px; border-radius: 50%;
  background: var(--accent); box-shadow: 0 0 0 4px rgba(224, 74, 63, .15);
}
.check-list.small li { font-size: 15px; padding-bottom: 10px; margin-bottom: 10px; }

.stats { background: var(--navy); color: #fff; padding: 56px 0 !important; }
.stat-list { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.stat-list li { display: flex; flex-direction: column; border-left: 3px solid var(--accent); padding-left: 20px; }
.stat-list .num { font-size: 46px; font-weight: 800; line-height: 1.1; }
.stat-list .num small { font-size: 18px; font-weight: 700; margin-left: 4px; color: rgba(255, 255, 255, .8); }
.stat-list .lab { font-size: 16px; color: rgba(255, 255, 255, .85); margin-top: 6px; }
.stat-note { margin: 28px 0 0; font-size: 14px; color: rgba(255, 255, 255, .7); }
.stat-note a { color: #fff; text-decoration: underline; }
/* 9584: visible heading on the dark stats band */
.home .stats .sec-head { margin-bottom: 32px; }
.home .stats .eyebrow { color: #ffb3ad; }
.home .stats h2 { color: #fff; }
.home .stats .link-more { color: #fff; }

.home-research { background: var(--soft); }
.cards { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(5, 1fr); gap: 18px; }
.card {
  background: var(--white); border-radius: var(--radius); padding: 26px 22px; border: 1px solid var(--line);
  box-shadow: 0 2px 8px rgba(12, 31, 61, .04); transition: transform .2s, box-shadow .2s; position: relative;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.card-no { font-size: 30px; font-weight: 800; color: var(--accent); line-height: 1; }
.card h3 { margin: 14px 0 10px; font-size: 18px; line-height: 1.4; color: var(--navy); }
.card p { margin: 0; font-size: 15px; color: var(--muted); line-height: 1.7; }

.units { list-style: none; margin: 0 0 40px; padding: 0; display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.units li { border-top: 3px solid var(--navy); background: var(--soft); border-radius: 0 0 var(--radius) var(--radius); padding: 22px; }
.units h3 { margin: 0 0 8px; font-size: 17px; color: var(--navy); line-height: 1.45; }
.units p { margin: 0; font-size: 15px; color: var(--muted); }
.feature { display: grid; grid-template-columns: 1.2fr 1fr; gap: 44px; align-items: center; background: var(--soft-2); border-radius: 20px; padding: 36px; }
.feature-media { margin: 0; background: #fff; border-radius: 12px; padding: 10px; }
.feature h3 { margin: 0 0 12px; font-size: 24px; color: var(--navy); line-height: 1.4; }
.feature-text > p { color: var(--ink); }
.feature .btn { margin-top: 14px; }

.home-people { background: var(--soft); }
.people-strip { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(7, 1fr); gap: 18px; }
.people-strip a { display: flex; flex-direction: column; align-items: center; text-align: center; color: var(--ink); text-decoration: none !important; }
.people-strip img { width: 120px; height: 150px; object-fit: cover; border-radius: 12px; box-shadow: 0 4px 14px rgba(12, 31, 61, .12); background: #fff; }
.people-strip .pname { font-weight: 800; margin-top: 12px; color: var(--navy); }
.people-strip .prole { font-size: 13px; color: var(--muted); line-height: 1.5; }

/* ---------------- sub pages ---------------- */
.page-banner {
  color: #fff; padding: 64px 0 56px;
  background:
    radial-gradient(circle at 90% 0%, rgba(123, 86, 201, .35), transparent 40%),
    linear-gradient(120deg, var(--navy) 0%, var(--navy-2) 70%, var(--navy-3) 100%);
}
.page-banner h1 { margin: 6px 0 0; font-size: 42px; font-weight: 800; letter-spacing: -.01em; }
.breadcrumb ol { list-style: none; display: flex; flex-wrap: wrap; gap: 8px; margin: 0; padding: 0; font-size: 14px; color: rgba(255, 255, 255, .78); }
.breadcrumb li + li::before { content: "\203A"; margin-right: 8px; }
.breadcrumb a { color: rgba(255, 255, 255, .9); }

.page-body { display: grid; grid-template-columns: 250px minmax(0, 1fr); gap: 56px; padding-top: 48px; padding-bottom: 96px; align-items: start; }
.subnav { position: sticky; top: calc(var(--header-h) + 20px); max-height: calc(100vh - var(--header-h) - 40px); overflow-y: auto; }
.subnav-box { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; background: var(--white); }
.subnav-box summary {
  list-style: none; cursor: pointer; padding: 18px 20px; background: var(--navy); color: #fff; font-weight: 800; font-size: 19px;
}
.subnav-box summary::-webkit-details-marker { display: none; }
.subnav-box ul { list-style: none; margin: 0; padding: 8px 0; }
.subnav-box li a { display: block; padding: 7px 20px; color: var(--ink); font-size: 15px; line-height: 1.5; border-left: 3px solid transparent; }
.subnav-box li.toc-l1 a { font-weight: 700; }
.subnav-box li.toc-l2 a { padding-left: 34px; font-size: 14px; color: var(--muted); }
.subnav-box li a:hover, .subnav-box li a.is-current { background: var(--soft); color: var(--navy-3); border-left-color: var(--accent); text-decoration: none; }

.content { min-width: 0; }
.content .sec { scroll-margin-top: calc(var(--header-h) + 16px); }
.content .sec-l1 { margin-bottom: 64px; }
.content .sec-l1:last-child { margin-bottom: 0; }
.content h2 {
  font-size: 28px; line-height: 1.4; color: var(--navy); margin: 0 0 24px; padding-bottom: 14px;
  border-bottom: 2px solid var(--navy); position: relative;
}
.content h2::after { content: ""; position: absolute; left: 0; bottom: -2px; width: 64px; height: 2px; background: var(--accent); }
.content h3 { font-size: 21px; line-height: 1.45; color: var(--navy-2); margin: 44px 0 16px; padding-left: 14px; border-left: 4px solid var(--accent); }
.content h4 { font-size: 18px; margin: 0 0 6px; color: var(--navy); }
.content p { margin: 0 0 16px; }
.content .para-head { margin-top: 28px; font-size: 18px; color: var(--navy); }
.content ul { margin: 0 0 20px; padding-left: 22px; }
.content li { margin: 6px 0; }
.content li::marker { color: var(--accent); }
.content ul ul { margin: 6px 0 8px; padding-left: 20px; list-style: circle; }
.content ul ul li { font-size: 15px; color: #303a48; }
.content ul ul li::marker { color: var(--navy-3); }

.greeting { background: var(--soft); border-radius: 20px; padding: 40px 44px; }
.greeting h2 { border-bottom-color: var(--line); }
.greeting .para-head { font-size: 22px; margin-top: 0; }
.greeting p { font-size: 17px; line-height: 1.9; }
.greeting .sign { text-align: right; font-weight: 700; color: var(--navy); margin-top: 28px; }

.table-wrap { width: 100%; overflow-x: auto; margin: 8px 0 28px; border-radius: 10px; border: 1px solid var(--line); -webkit-overflow-scrolling: touch; }
.table-wrap table { width: 100%; border-collapse: collapse; font-size: 15px; line-height: 1.65; }
.table-wrap caption { caption-side: top; text-align: left; font-weight: 800; color: var(--navy); padding: 14px 16px 10px; background: var(--white); }
.table-wrap thead th { background: var(--navy); color: #fff; font-weight: 700; text-align: left; padding: 12px 16px; }
.table-wrap td, .table-wrap tbody th { padding: 12px 16px; border-top: 1px solid var(--line); vertical-align: top; text-align: left; }
.table-wrap tbody th { background: var(--soft); color: var(--navy); font-weight: 700; }
.table-wrap tbody tr:hover td { background: #fafbfd; }
.nw { white-space: nowrap; }

.fig { margin: 12px 0 32px; text-align: center; }
.fig .fig-link { display: inline-block; width: var(--w, 100%); max-width: 100%; }
.fig img { width: 100%; margin: 0 auto; border: 1px solid var(--line); border-radius: 10px; background: #fff; }
.fig figcaption { margin: 10px auto 0; max-width: 880px; font-size: 14px; color: var(--muted); line-height: 1.6; }

.people-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; margin-bottom: 12px; }
.person { display: flex; gap: 22px; padding: 22px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--white); box-shadow: 0 2px 8px rgba(12, 31, 61, .04); }
.person-photo { flex: 0 0 112px; }
.person-photo img { width: 112px; height: 140px; object-fit: cover; border-radius: 10px; background: var(--soft); }
.person-photo .avatar {
  width: 112px; height: 140px; border-radius: 10px; display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, var(--soft-2), #dfe5f0); color: var(--navy-3); font-size: 40px; font-weight: 800;
}
.person-body { min-width: 0; }
.person-name { font-size: 20px !important; margin: 2px 0 8px !important; }
.person ul { list-style: none; padding: 0; margin: 0; font-size: 15px; }
.person li { margin: 4px 0; }
#director .people-grid { grid-template-columns: minmax(0, 1fr); max-width: 620px; }

/* ---------------- footer ---------------- */
.site-footer { background: #0a1730; color: rgba(255, 255, 255, .78); font-size: 14px; }
.footer-inner { display: grid; grid-template-columns: 1.1fr 1.6fr .8fr; gap: 40px; padding-top: 52px; padding-bottom: 36px; }
.footer-brand { display: flex; gap: 14px; align-items: flex-start; }
.footer-brand img { height: 64px; width: auto; background: #fff; padding: 6px 10px; border-radius: 10px; flex-shrink: 0; }
.footer-brand div { display: flex; flex-direction: column; line-height: 1.6; }
.footer-brand strong { color: #fff; font-size: 17px; }
.footer-contact, .footer-links { list-style: none; margin: 0; padding: 0; }
.footer-contact li { margin-bottom: 6px; }
.footer-links { display: grid; grid-template-columns: repeat(2, auto); gap: 6px 24px; align-content: start; }
.footer-links a { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255, 255, 255, .12); padding-top: 18px; padding-bottom: 28px; font-size: 13px; color: rgba(255, 255, 255, .55); }

/* ---------------- responsive ---------------- */
@media (max-width: 1180px) {
  .cards { grid-template-columns: repeat(3, 1fr); }
  .people-strip { grid-template-columns: repeat(4, 1fr); row-gap: 28px; }
  .nav-top { padding: 0 14px; }
  .nav-top::after { left: 14px; right: 14px; }
}
@media (max-width: 960px) {
  :root { --header-h: 64px; }
  .nav-toggle { display: flex; }
  .site-nav {
    display: none; position: absolute; left: 0; right: 0; top: var(--header-h);
    background: var(--white); border-top: 1px solid var(--line); box-shadow: var(--shadow);
    max-height: calc(100vh - var(--header-h)); overflow-y: auto;
  }
  .site-nav.is-open { display: block; }
  .site-nav .nav-list { flex-direction: column; gap: 0; padding: 8px 0 16px; }
  .nav-top { line-height: 1.4; padding: 14px 24px; font-size: 18px; border-bottom: 1px solid var(--line); }
  .nav-top::after { display: none; }
  .dropdown {
    position: static; transform: none; opacity: 1; visibility: visible; box-shadow: none; border: 0;
    min-width: 0; padding: 4px 0 10px; background: var(--soft); border-radius: 0;
  }
  .nav-item:hover .dropdown, .nav-item:focus-within .dropdown { transform: none; }
  .dropdown a { padding: 8px 36px; white-space: normal; }
  .brand-ko { font-size: 15px; }

  .slides, .slide-inner { min-height: 0; }
  .slide-inner { grid-template-columns: 1fr; gap: 28px; padding-top: 36px; padding-bottom: 96px; }
  .slide-media { order: -1; }
  .slide-media img { max-height: 260px; }
  .home .slide-head { font-size: 26px; }
  .slide-desc { font-size: 16px; }

  .home section:not(.hero) { padding: 60px 0; }
  .home h2 { font-size: 25px; }
  .intro-grid, .feature { grid-template-columns: 1fr; gap: 28px; }
  .feature { padding: 22px; }
  .stat-list { grid-template-columns: repeat(2, 1fr); row-gap: 28px; }
  .stat-list .num { font-size: 36px; }
  .units { grid-template-columns: repeat(2, 1fr); }
  .cards { grid-template-columns: repeat(2, 1fr); }
  .sec-head { flex-wrap: wrap; align-items: flex-start; }

  .page-banner { padding: 40px 0 36px; }
  .page-banner h1 { font-size: 32px; }
  .page-body { grid-template-columns: 1fr; gap: 28px; padding-top: 24px; padding-bottom: 64px; }
  .subnav { position: static; max-height: none; overflow: visible; }
  .subnav-box summary { font-size: 17px; padding: 14px 18px; }
  .subnav-box summary::after { content: "+"; float: right; font-weight: 400; }
  .subnav-box[open] summary::after { content: "\2212"; }
  .people-grid { grid-template-columns: 1fr; }
  .fig .fig-link { width: 100%; }
  .footer-inner { grid-template-columns: 1fr; gap: 24px; }
}
@media (max-width: 560px) {
  .brand { gap: 8px; flex-shrink: 1; min-width: 0; }
  .nav-toggle { flex-shrink: 0; }
  .brand img { height: 40px; }
  .brand-ko { font-size: 14px; }
  .fig .fig-link { width: 100%; }
  .wrap { padding-left: 16px; padding-right: 16px; }
  .cards, .units { grid-template-columns: 1fr; }
  .people-strip { grid-template-columns: repeat(2, 1fr); }
  .people-strip img { width: 110px; height: 138px; }
  .content h2 { font-size: 23px; }
  .content h3 { font-size: 19px; }
  .greeting { padding: 26px 20px; }
  .person { padding: 16px; gap: 16px; }
  .person-photo { flex-basis: 84px; }
  .person-photo img, .person-photo .avatar { width: 84px; height: 105px; }
  .person-photo .avatar { font-size: 30px; }
  .table-wrap table { font-size: 14px; }
  .table-wrap td, .table-wrap tbody th, .table-wrap thead th { padding: 10px 12px; }
}
@media (prefers-reduced-motion: reduce) {
  .slide, .card, .dropdown, .nav-top::after { transition: none; }
}