/* ==========================================================================
   DATANG HOLDINGS — Corporate Site Framework
   style.css  (한국어/영어 2개 언어, 반응형: Mobile / Tablet / Desktop)
   ========================================================================== */

/* ---------- 1. Tokens ---------------------------------------------------- */
:root {
  /* type scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.0625rem);
  --text-lg: clamp(1.125rem, 1rem + 0.6vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.2vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.4vw, 3.25rem);

  /* spacing (4px base) */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* color */
  --navy-900: #0a1a2f;
  --navy-800: #0f2440;
  --navy-700: #163353;
  --navy-600: #1e4470;
  --steel-600: #4b5a6b;
  --ink: #16202b;
  --ink-2: #47566a;
  --ink-3: #7d8a99;
  --line: #e2e7ee;
  --line-2: #cfd7e2;
  --surface: #ffffff;
  --surface-2: #f5f7fa;
  --surface-3: #eef2f7;
  --accent: #0a84c8;
  --accent-2: #00b4a6;
  --accent-3: #c8332f;
  --accent-4: #6aa84f;

  /* layout */
  --side-w: 264px;
  --topbar-h: 60px;
  --radius: 3px;
  --shadow-1: 0 1px 2px rgba(10, 26, 47, 0.06), 0 6px 24px rgba(10, 26, 47, 0.06);
  --shadow-2: 0 10px 40px rgba(10, 26, 47, 0.12);
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);

  --font-sans: "Pretendard", "Inter", -apple-system, BlinkMacSystemFont,
    "Malgun Gothic", "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  --font-zh: "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC",
    "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  --font-ja: "Inter", -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN",
    "Yu Gothic", "Meiryo", "Noto Sans JP", sans-serif;
}

/* 중국어·일본어 선택 시 본문 글꼴 및 줄바꿈 규칙 교체 */
html[lang="zh"] body { font-family: var(--font-zh); }
html[lang="ja"] body { font-family: var(--font-ja); }
html[lang="zh"] body,
html[lang="ja"] body { word-break: normal; line-break: strict; }
/* 4개 언어 모두 같은 글자 크기를 사용한다(언어 전환 시 크기 변동 없음).
   중국어·일본어는 자간과 줄 간격만 미세 조정 */
html[lang="zh"] .hero h1,
html[lang="ja"] .hero h1 { letter-spacing: -0.012em; line-height: 1.14; }
html[lang="zh"] .h-sec,
html[lang="ja"] .h-sec { letter-spacing: -0.005em; }

/* ---------- 2. Reset ---------------------------------------------------- */
*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.75;
  color: var(--ink);
  background: var(--surface);
  -webkit-font-smoothing: antialiased;
  word-break: keep-all;
  overflow-wrap: break-word;
}

img, svg { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4, p { margin: 0; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* ---------- 3. 언어 전환 (KOR / ENG) ------------------------------------- */
/* 활성 언어 요소는 자체 display 값을 그대로 유지하고, 비활성 언어만 숨긴다 */
html[lang="ko"] [data-lang]:not([data-lang="ko"]),
html[lang="en"] [data-lang]:not([data-lang="en"]),
html[lang="zh"] [data-lang]:not([data-lang="zh"]),
html[lang="ja"] [data-lang]:not([data-lang="ja"]) { display: none !important; }

/* ---------- 4. Sidebar (Desktop) ---------------------------------------- */
.side {
  position: fixed;
  inset: 0 auto 0 0;
  width: var(--side-w);
  background: var(--surface);
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  z-index: 60;
}

.side__brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-6) var(--space-6) var(--space-5);
  border-bottom: 1px solid var(--line);
}
.brand-mark { width: 34px; height: 34px; color: var(--navy-800); flex: none; }
.brand-text { line-height: 1.15; }
.brand-text b {
  display: block;
  font-size: 1rem;
  letter-spacing: 0.12em;
  font-weight: 800;
  color: var(--navy-900);
}
.brand-text span {
  display: block;
  font-size: 0.6875rem;
  letter-spacing: 0.22em;
  color: var(--ink-3);
  text-transform: uppercase;
}

/* language switch */
.lang-switch {
  display: grid;
  grid-template-columns: 1fr 1fr;
  border-bottom: 1px solid var(--line);
}
.lang-switch button:nth-child(-n + 2) { border-bottom: 1px solid var(--line); }
.lang-switch button:nth-child(2n) { border-right: 0; }
.lang-switch button {
  padding: var(--space-2) 0;
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--ink-3);
  background: var(--surface-2);
  border-right: 1px solid var(--line);
  transition: color 0.2s, background 0.2s;
}

.lang-switch button:hover { color: var(--navy-700); }
.lang-switch button[aria-pressed="true"] { background: var(--surface); color: var(--accent); }

/* nav */
.side__nav { flex: 1 1 auto; overflow-y: auto; padding-bottom: var(--space-6); }
.nav-item { border-bottom: 1px solid var(--line); }
.nav-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  width: 100%;
  padding: var(--space-4) var(--space-6);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--ink);
  transition: color 0.2s, background 0.2s;
}
.nav-link:hover { color: var(--accent); background: var(--surface-2); }
.nav-item.is-active .nav-link { color: var(--accent); }
.nav-item.is-active .nav-link::before {
  content: "";
  position: absolute;
  left: 0;
  width: 3px;
  height: 22px;
  background: var(--accent);
}
.nav-link { position: relative; }
.nav-row { display: flex; align-items: stretch; }
.nav-row .nav-link { flex: 1 1 auto; padding-right: var(--space-2); }
.chev {
  flex: none; width: 46px;
  display: flex; align-items: center; justify-content: center;
  background: none; border: 0; cursor: pointer;
  color: var(--ink-3);
  transition: color 0.2s, background 0.2s;
}
.chev:hover { color: var(--accent); background: var(--surface-2); }
.chev i {
  width: 8px; height: 8px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg) translate(-2px, -2px);
  transition: transform 0.25s var(--ease);
}
.nav-item.is-open .chev i { transform: rotate(-135deg); }
.nav-item.is-active .chev { color: var(--accent); }

.nav-sub {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.3s var(--ease);
  background: var(--surface-2);
}
.nav-item.is-open .nav-sub { grid-template-rows: 1fr; }
.nav-sub > div { overflow: hidden; }
.nav-sub a {
  display: block;
  padding: var(--space-2) var(--space-6) var(--space-2) var(--space-8);
  font-size: var(--text-xs);
  color: var(--ink-2);
}
.nav-sub a:first-child { padding-top: var(--space-3); }
.nav-sub a:last-child { padding-bottom: var(--space-4); }
.nav-sub a:hover { color: var(--accent); }

/* sidebar foot */
.side__foot {
  padding: var(--space-5) var(--space-6) var(--space-6);
  border-top: 1px solid var(--line);
  font-size: var(--text-xs);
  color: var(--ink-3);
}
.side__foot .fs {
  width: 100%;
  padding: var(--space-2) var(--space-3);
  margin-bottom: var(--space-4);
  font-size: var(--text-xs);
  color: var(--ink-2);
  background: var(--surface-2);
  border: 1px solid var(--line-2);
  border-radius: var(--radius);
}
.side__foot ul { margin-bottom: var(--space-3); }
.side__foot li + li { margin-top: 2px; }
.side__foot a:hover { color: var(--accent); }

/* ---------- 5. Topbar (Mobile / Tablet) --------------------------------- */
.topbar {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--topbar-h);
  display: none;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  padding: 0 var(--space-4);
  background: rgba(255, 255, 255, 0.94);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
  z-index: 70;
}
.topbar .brand-mark { width: 28px; height: 28px; }
.topbar__brand { display: flex; align-items: center; gap: var(--space-2); }
.topbar__right { display: flex; align-items: center; gap: var(--space-2); }
.lang-mini {
  display: flex;
  border: 1px solid var(--line-2);
  border-radius: var(--radius);
  overflow: hidden;
}
@media (max-width: 519px) {
  .lang-mini button { padding: 5px 6px; font-size: 0.625rem; letter-spacing: 0; }
}
@media (max-width: 379px) {
  .topbar__right { gap: 0; }
  .lang-mini button { padding: 5px 3px; font-size: 0.5625rem; }
  .burger { width: 34px; }
  .topbar .brand-text span { display: none; }
  .topbar .brand-text b { font-size: 0.8125rem; }
}
@media (max-width: 339px) {
  .topbar .brand-text { display: none; }
}
.lang-mini button {
  padding: 5px 9px;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  white-space: nowrap;
  color: var(--ink-3);
}
.lang-mini button[aria-pressed="true"] { background: var(--navy-800); color: #fff; }

.burger { width: 40px; height: 40px; display: grid; place-items: center; }
.burger i {
  position: relative;
  display: block;
  width: 20px; height: 1.5px;
  background: var(--navy-900);
  transition: transform 0.25s var(--ease), opacity 0.2s;
}
.burger i::before, .burger i::after {
  content: ""; position: absolute; left: 0;
  width: 20px; height: 1.5px; background: var(--navy-900);
  transition: transform 0.25s var(--ease);
}
.burger i::before { top: -6px; }
.burger i::after { top: 6px; }
body.nav-open .burger i { background: transparent; }
body.nav-open .burger i::before { transform: translateY(6px) rotate(45deg); }
body.nav-open .burger i::after { transform: translateY(-6px) rotate(-45deg); }

.scrim {
  position: fixed; inset: 0;
  background: rgba(10, 26, 47, 0.45);
  opacity: 0; visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
  z-index: 55;
}
body.nav-open .scrim { opacity: 1; visibility: visible; }

/* ---------- 6. Main / Layout -------------------------------------------- */
.main { margin-left: var(--side-w); min-height: 100vh; }
.wrap { width: 100%; max-width: 1180px; margin: 0 auto; padding: 0 var(--space-6); }
.section { padding-block: clamp(var(--space-12), 6vw, var(--space-24)); }
.section--tint { background: var(--surface-2); }
.section--dark { background: var(--navy-900); color: #dbe4ee; }

/* ---------- 7. Type helpers -------------------------------------------- */
.eyebrow {
  display: inline-flex; align-items: center; gap: var(--space-2);
  font-size: var(--text-xs); font-weight: 700;
  letter-spacing: 0.2em; text-transform: uppercase; color: var(--accent);
}
.eyebrow::before { content: ""; width: 22px; height: 2px; background: currentColor; }
.h-sec {
  font-size: var(--text-xl); font-weight: 800; line-height: 1.3;
  letter-spacing: -0.01em; color: var(--navy-900);
  margin-top: var(--space-3);
}
.section--dark .h-sec { color: #fff; }
.h-card { font-size: var(--text-lg); font-weight: 700; line-height: 1.35; color: var(--navy-900); }
.lead { margin-top: var(--space-4); color: var(--ink-2); max-width: 62ch; }
.section--dark .lead { color: #a9bacd; }
.sec-head { margin-bottom: clamp(var(--space-8), 4vw, var(--space-12)); }
.body-copy p + p { margin-top: var(--space-4); }
.body-copy { color: var(--ink-2); }
.accent-bar {
  width: 4px; height: 46px; flex: none;
  background: linear-gradient(180deg, var(--accent-3), var(--ink-3) 45%, var(--accent));
}

/* ---------- 8. Buttons ------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-sm); font-weight: 700;
  border: 1px solid var(--navy-800); border-radius: var(--radius);
  background: var(--navy-800); color: #fff;
  transition: background 0.2s, color 0.2s, transform 0.2s;
}
.btn:hover { background: var(--accent); border-color: var(--accent); }
.btn--ghost { background: transparent; color: var(--navy-800); }
.btn--ghost:hover { background: var(--navy-800); color: #fff; border-color: var(--navy-800); }
.btn--light { background: #fff; border-color: #fff; color: var(--navy-900); }
.btn--light:hover { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn .arw { transition: transform 0.2s var(--ease); }
.btn:hover .arw { transform: translateX(4px); }

/* ---------- 9. Hero (Home) --------------------------------------------- */
.hero { display: grid; grid-template-columns: 1fr 392px; min-height: calc(100vh - 0px); }
.hero__main {
  position: relative;
  display: flex; flex-direction: column; justify-content: center;
  padding: clamp(var(--space-12), 7vw, var(--space-24)) clamp(var(--space-6), 5vw, var(--space-20));
  background:
    radial-gradient(1100px 620px at 12% 18%, rgba(10, 132, 200, 0.10), transparent 62%),
    linear-gradient(160deg, #f7fafd 0%, #eaf0f7 100%);
  overflow: hidden;
}
.hero__grid-bg {
  position: absolute; inset: 0; pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(22, 51, 83, 0.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(22, 51, 83, 0.055) 1px, transparent 1px);
  background-size: 46px 46px;
  -webkit-mask-image: radial-gradient(circle at 30% 40%, #000 0%, transparent 78%);
  mask-image: radial-gradient(circle at 30% 40%, #000 0%, transparent 78%);
}
.hero__inner { position: relative; max-width: 660px; }
.hero__kicker {
  font-size: var(--text-xs); font-weight: 700;
  letter-spacing: 0.28em; text-transform: uppercase; color: var(--ink-3);
}
.hero h1 {
  margin-top: var(--space-4);
  font-size: var(--text-2xl);
  font-weight: 800; line-height: 1.08;
  letter-spacing: -0.02em; color: var(--navy-900);
}
.hero h1 em { font-style: normal; color: var(--accent); }
.hero__sub { margin-top: var(--space-5); font-size: var(--text-base); color: var(--ink-2); max-width: 54ch; }
.hero__cta { display: flex; flex-wrap: wrap; gap: var(--space-3); margin-top: var(--space-8); }
.hero__stats {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-4);
  margin-top: clamp(var(--space-10), 5vw, var(--space-16));
  padding-top: var(--space-6);
  border-top: 1px solid var(--line-2);
  max-width: 620px;
}
.hero__stats b { display: block; font-size: var(--text-lg); font-weight: 800; color: var(--navy-800); }
.hero__stats span { font-size: var(--text-xs); color: var(--ink-3); }

/* right tile column (현대머티리얼 스타일 타일) */
.tiles { display: grid; grid-template-rows: repeat(4, 1fr); border-left: 1px solid var(--line); }
.tile {
  position: relative;
  display: flex; flex-direction: column; justify-content: center;
  gap: var(--space-2);
  padding: var(--space-8) var(--space-6);
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  color: #fff;
  overflow: hidden;
  transition: background 0.3s var(--ease);
}
.tile:nth-child(1) { background: var(--navy-800); }
.tile:nth-child(2) { background: var(--navy-700); }
.tile:nth-child(3) { background: var(--navy-600); }
.tile:nth-child(4) { background: #1c5a86; border-bottom: 0; }
.tile:hover { background: var(--accent); }
.tile svg { width: 30px; height: 30px; color: rgba(255, 255, 255, 0.9); }
.tile b { font-size: var(--text-base); font-weight: 700; }
.tile span { font-size: var(--text-xs); color: rgba(255, 255, 255, 0.72); line-height: 1.6; }
.tile .arw-abs {
  position: absolute; right: var(--space-6); bottom: var(--space-5);
  opacity: 0.55; transition: transform 0.25s var(--ease);
}
.tile:hover .arw-abs { transform: translateX(5px); opacity: 1; }

/* ---------- 10. Cards / Grids ------------------------------------------ */
.grid { display: grid; gap: var(--space-6); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.card {
  display: flex; flex-direction: column; gap: var(--space-3);
  padding: var(--space-6);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.25s, box-shadow 0.25s, transform 0.25s var(--ease);
}
.card:hover { border-color: var(--accent); box-shadow: var(--shadow-1); transform: translateY(-3px); }
.card__no {
  font-size: var(--text-xs); font-weight: 800;
  letter-spacing: 0.16em; color: var(--accent);
}
.card p { font-size: var(--text-sm); color: var(--ink-2); }
.card ul.tags { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: auto; padding-top: var(--space-2); }
.tags li {
  padding: 3px var(--space-3);
  font-size: var(--text-xs); color: var(--ink-2);
  background: var(--surface-3); border-radius: 100px;
}
.card--dark { background: var(--navy-800); border-color: transparent; color: #cfdbe8; }
.card--dark .h-card { color: #fff; }
.card--dark p { color: #a9bacd; }

/* division cards with color key */
.dcard { border-top: 3px solid var(--accent); }
.dcard--oil { border-top-color: #d4711f; }
.dcard--lng { border-top-color: #0a84c8; }
.dcard--new { border-top-color: #6aa84f; }
.dcard--log { border-top-color: #6b7684; }
.dcard--trade { border-top-color: #b4462f; }
.dcard--future { border-top-color: #7b52ab; }

/* ---------- 11. Page header -------------------------------------------- */
.page-head {
  position: relative;
  padding: clamp(var(--space-16), 9vw, var(--space-24)) 0 clamp(var(--space-10), 5vw, var(--space-16));
  background: linear-gradient(140deg, var(--navy-900) 0%, var(--navy-700) 58%, #17537d 100%);
  color: #fff;
  overflow: hidden;
}
.page-head::after {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(255, 255, 255, 0.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255, 255, 255, 0.055) 1px, transparent 1px);
  background-size: 44px 44px;
  -webkit-mask-image: linear-gradient(115deg, #000, transparent 72%);
  mask-image: linear-gradient(115deg, #000, transparent 72%);
}
.page-head .wrap { position: relative; z-index: 1; }
.page-head h1 {
  margin-top: var(--space-3);
  font-size: var(--text-xl); font-weight: 800; letter-spacing: -0.01em;
}
.page-head .eyebrow { color: #6fd0f5; }
.page-head p { margin-top: var(--space-4); color: #a9c3da; max-width: 62ch; font-size: var(--text-sm); }
.crumb {
  display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2);
  margin-top: var(--space-6);
  font-size: var(--text-xs); color: rgba(255, 255, 255, 0.6);
}
.crumb > span + span::before { content: "/"; margin-right: var(--space-2); opacity: 0.5; }

/* in-page tabs */
.tabs {
  position: sticky; top: 0; z-index: 40;
  background: rgba(255, 255, 255, 0.96);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.tabs ul { display: flex; overflow-x: auto; scrollbar-width: none; }
.tabs ul::-webkit-scrollbar { display: none; }
.tabs a {
  display: block; white-space: nowrap;
  padding: var(--space-4) var(--space-5);
  font-size: var(--text-sm); font-weight: 600; color: var(--ink-3);
  border-bottom: 2px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}
.tabs a:hover { color: var(--navy-800); }
.tabs a.is-active { color: var(--accent); border-bottom-color: var(--accent); }

/* ---------- 12. Split rows / definition tables ------------------------- */
.split { display: grid; grid-template-columns: 300px 1fr; gap: clamp(var(--space-6), 4vw, var(--space-16)); }
.split--wide { grid-template-columns: 1fr 1fr; }
.split__title { display: flex; gap: var(--space-4); }

.dl { border-top: 2px solid var(--navy-800); }
.dl__row {
  display: grid; grid-template-columns: 200px 1fr;
  border-bottom: 1px solid var(--line);
}
.dl__row dt {
  padding: var(--space-4) var(--space-5);
  font-size: var(--text-sm); font-weight: 700; color: var(--navy-900);
  background: var(--surface-2);
}
.dl__row dd { margin: 0; padding: var(--space-4) var(--space-5); font-size: var(--text-sm); color: var(--ink-2); }

.tbl-wrap { overflow-x: auto; }
table.tbl { width: 100%; border-collapse: collapse; min-width: 560px; }
table.tbl th, table.tbl td {
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-sm); text-align: left;
  border-bottom: 1px solid var(--line);
}
table.tbl thead th {
  background: var(--navy-800); color: #fff; font-weight: 700;
  border-bottom: 0; white-space: nowrap;
}
table.tbl tbody tr:hover { background: var(--surface-2); }
table.tbl td { color: var(--ink-2); }
table.tbl td:first-child { font-weight: 600; color: var(--ink); }

/* ---------- 13. Org chart / timeline ----------------------------------- */
.org { display: grid; gap: var(--space-4); }
.org__root {
  padding: var(--space-5) var(--space-6);
  text-align: center; font-weight: 800; color: #fff;
  background: var(--navy-800); border-radius: var(--radius);
}
.org__branch { display: grid; gap: var(--space-3); }
.org__node {
  display: flex; align-items: center; gap: var(--space-4);
  padding: var(--space-4) var(--space-5);
  background: var(--surface);
  border: 1px solid var(--line-2);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius);
  transition: transform 0.2s var(--ease), box-shadow 0.2s;
}
.org__node:hover { transform: translateX(4px); box-shadow: var(--shadow-1); }
.org__node > div { display: flex; flex-direction: column; gap: 5px; }
.org__node b { font-size: var(--text-sm); font-weight: 700; }
.org__node > div > span { font-size: var(--text-xs); color: var(--ink-3); line-height: 1.6; }

.timeline { position: relative; padding-left: var(--space-8); }
.timeline::before {
  content: ""; position: absolute; left: 6px; top: 6px; bottom: 6px;
  width: 2px; background: var(--line-2);
}
.timeline li { position: relative; padding-bottom: var(--space-8); }
.timeline li:last-child { padding-bottom: 0; }
.timeline li::before {
  content: ""; position: absolute; left: calc(var(--space-8) * -1 + 1px);
  top: 8px; width: 12px; height: 12px;
  background: #fff; border: 3px solid var(--accent); border-radius: 50%;
}
.timeline .t-year { font-size: var(--text-xs); font-weight: 800; letter-spacing: 0.12em; color: var(--accent); }
.timeline .t-body { margin-top: var(--space-1); font-size: var(--text-sm); color: var(--ink-2); }
.timeline .t-title { font-weight: 700; color: var(--navy-900); }

/* bullets */
.bul li {
  position: relative; padding-left: var(--space-5);
  font-size: var(--text-sm); color: var(--ink-2);
}
.bul li + li { margin-top: var(--space-2); }
.bul li::before {
  content: ""; position: absolute; left: 0; top: 0.72em;
  width: 6px; height: 6px; background: var(--accent); border-radius: 50%;
}

/* ---------- 14. CTA band + footer -------------------------------------- */
.cta-band {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between;
  gap: var(--space-6);
  padding: clamp(var(--space-8), 4vw, var(--space-12));
  background: linear-gradient(120deg, var(--navy-900), #17537d);
  border-radius: var(--radius);
  color: #fff;
}
.cta-band h2 { font-size: var(--text-lg); font-weight: 800; }
.cta-band p { margin-top: var(--space-2); font-size: var(--text-sm); color: #a9c3da; }

.footer { padding: var(--space-12) 0 var(--space-10); background: var(--navy-900); color: #8fa3b8; }
.footer a:hover { color: #fff; }
.footer__top {
  display: flex; flex-wrap: wrap; gap: var(--space-8);
  justify-content: space-between;
  padding-bottom: var(--space-8);
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}
.footer__links { display: flex; flex-wrap: wrap; gap: var(--space-6); font-size: var(--text-sm); }
.footer__meta { margin-top: var(--space-6); font-size: var(--text-xs); line-height: 1.9; }
.footer__meta b { color: #cfdbe8; font-weight: 600; }
.footer .brand-text b { color: #fff; }
.footer .brand-mark { color: #fff; }

/* ---------- 15. Form --------------------------------------------------- */
.form { display: grid; gap: var(--space-5); }
.field { display: grid; gap: var(--space-2); }
.field label { font-size: var(--text-xs); font-weight: 700; color: var(--navy-900); }
.field input, .field select, .field textarea {
  width: 100%; padding: var(--space-3) var(--space-4);
  font: inherit; font-size: var(--text-sm); color: var(--ink);
  background: #fff; border: 1px solid var(--line-2); border-radius: var(--radius);
  transition: border-color 0.2s, box-shadow 0.2s;
}
.field textarea { min-height: 150px; resize: vertical; }
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none; border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(10, 132, 200, 0.14);
}
.form-note { font-size: var(--text-xs); color: var(--ink-3); }
.form-msg {
  display: none; padding: var(--space-4);
  font-size: var(--text-sm);
  background: #eef8f2; border: 1px solid #b8e0c8; border-radius: var(--radius); color: #1d6b3f;
}
.form-msg.is-on { display: block; }

/* ---------- 16. Reveal animation --------------------------------------- */
.rv { opacity: 0; transform: translateY(18px); transition: opacity 0.6s var(--ease), transform 0.6s var(--ease); }
.rv.is-in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .rv { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ---------- 17. Top button -------------------------------------------- */
.to-top {
  position: fixed; right: var(--space-5); bottom: var(--space-5);
  width: 44px; height: 44px; display: grid; place-items: center;
  background: var(--navy-800); color: #fff; border-radius: 50%;
  box-shadow: var(--shadow-2);
  opacity: 0; visibility: hidden; transform: translateY(8px);
  transition: opacity 0.25s, visibility 0.25s, transform 0.25s, background 0.2s;
  z-index: 50;
}
.to-top.is-on { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { background: var(--accent); }

/* ==========================================================================
   18. Responsive — Desktop(≥1120) / Tablet(720–1119) / Mobile(<720)
   ========================================================================== */
@media (max-width: 1279px) {
  .hero { grid-template-columns: 1fr 330px; }
}

@media (max-width: 1119px) {
  .side {
    transform: translateX(-100%);
    transition: transform 0.32s var(--ease);
    box-shadow: none;
    width: min(320px, 86vw);
  }
  body.nav-open .side { transform: none; box-shadow: var(--shadow-2); }
  .topbar { display: flex; }
  .main { margin-left: 0; padding-top: var(--topbar-h); }
  .side__brand { padding-top: var(--space-5); }
  .side .lang-switch { display: none; } /* 상단바에 이미 KOR/ENG가 있으므로 중복 제거 */

  .hero { grid-template-columns: 1fr; min-height: 0; }
  .hero__main { min-height: calc(78vh - var(--topbar-h)); }
  .tiles { grid-template-rows: none; grid-template-columns: repeat(2, 1fr); border-left: 0; }
  .tile { border-right: 1px solid rgba(255, 255, 255, 0.12); min-height: 168px; }
  .tile:nth-child(4) { border-bottom: 0; }

  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .split { grid-template-columns: 1fr; }
  .split--wide { grid-template-columns: 1fr; }
}

@media (max-width: 860px) {
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 719px) {
  .wrap { padding: 0 var(--space-4); }
  .grid { gap: var(--space-4); }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: 1fr; }
  .tiles { grid-template-columns: 1fr; }
  .tile { min-height: 0; padding: var(--space-6) var(--space-5); }
  .hero__stats { grid-template-columns: 1fr 1fr; gap: var(--space-3); }
  .dl__row { grid-template-columns: 1fr; }
  .dl__row dt { padding-bottom: var(--space-2); }
  .dl__row dd { padding-top: var(--space-2); }
  .cta-band { flex-direction: column; align-items: flex-start; }
  .footer__top { flex-direction: column; gap: var(--space-6); }
}

/* print */
@media print {
  .side, .topbar, .to-top, .tabs, .scrim { display: none !important; }
  .main { margin: 0; padding: 0; }
  .page-head { background: #fff; color: #000; }
}

/* ==========================================================================
   19. 사진(Photography) & 모션 — 무료 라이선스 사진(Pexels) 사용
   ========================================================================== */

/* 공통: 사진 래퍼 */
.ph { position: relative; overflow: hidden; background: var(--surface-3); }
.ph img { width: 100%; height: 100%; object-fit: cover; display: block; }

/* ---------- 19-1. 히어로 (홈) ---------- */
.hero--photo {
  display: block;
  position: relative;
  min-height: clamp(480px, 78vh, 720px);
  padding: clamp(var(--space-16), 10vw, var(--space-24)) clamp(var(--space-6), 5vw, var(--space-20));
  display: flex; align-items: flex-end;
  background: var(--navy-900);
  overflow: hidden;
}
.hero--photo .hero__media { position: absolute; inset: 0; }
.hero--photo .hero__media img {
  width: 100%; height: 100%; object-fit: cover;
  transform: scale(1.04);
  animation: kenburns 26s ease-out forwards;
}
.hero--photo .hero__media::after {
  content: ""; position: absolute; inset: 0;
  background:
    linear-gradient(103deg, rgba(8, 22, 40, 0.94) 0%, rgba(8, 22, 40, 0.80) 42%, rgba(8, 22, 40, 0.34) 100%),
    linear-gradient(to top, rgba(8, 22, 40, 0.72) 0%, transparent 46%);
}
.hero--photo .hero__inner { position: relative; z-index: 1; max-width: 720px; color: #fff; }
.hero--photo .hero__kicker { color: rgba(255, 255, 255, 0.62); }
.hero--photo h1 { color: #fff; }
.hero--photo h1 em { color: #5cc8f5; }
.hero--photo .hero__sub { color: rgba(255, 255, 255, 0.80); }
.hero--photo .hero__stats { border-top-color: rgba(255, 255, 255, 0.22); }
.hero--photo .hero__stats b { color: #fff; }
.hero--photo .hero__stats span { color: rgba(255, 255, 255, 0.66); }
.hero--photo .btn--ghost { color: #fff; border-color: rgba(255, 255, 255, 0.5); }
.hero--photo .btn--ghost:hover { background: rgba(255, 255, 255, 0.12); border-color: #fff; }

@keyframes kenburns {
  from { transform: scale(1.02) translate3d(0, 0, 0); }
  to   { transform: scale(1.11) translate3d(0, -1.4%, 0); }
}

/* ---------- 19-2. 사진 타일 (홈 퀵링크) ---------- */
.tiles--photo {
  display: grid; grid-template-columns: repeat(4, 1fr);
  grid-template-rows: none;
  gap: 0; border-left: 0;
}
.tiles--photo .tile {
  position: relative; overflow: hidden;
  min-height: 268px;
  padding: var(--space-6) var(--space-6) var(--space-10);
  justify-content: flex-end;
  background: var(--navy-800);
  border-bottom: 0;
  border-right: 1px solid rgba(255, 255, 255, 0.10);
}
.tiles--photo .tile:last-child { border-right: 0; }
.tiles--photo .tile__media { position: absolute; inset: 0; }
.tiles--photo .tile__media img {
  width: 100%; height: 100%; object-fit: cover;
  transform: scale(1.01);
  transition: transform 0.9s var(--ease);
}
.tiles--photo .tile__media::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(to top, rgba(9, 24, 42, 0.94) 8%, rgba(9, 24, 42, 0.58) 52%, rgba(9, 24, 42, 0.34) 100%);
  transition: background 0.4s var(--ease);
}
.tiles--photo .tile > * { position: relative; z-index: 1; }
.tiles--photo .tile__media { position: absolute; z-index: 0; }
.tiles--photo .tile .arw-abs { position: absolute; z-index: 2; opacity: 0.72; }
.tiles--photo .tile:hover { background: var(--navy-800); }
.tiles--photo .tile:hover .tile__media img { transform: scale(1.09); }
.tiles--photo .tile:hover .tile__media::after {
  background: linear-gradient(to top, rgba(6, 74, 112, 0.95) 8%, rgba(9, 24, 42, 0.55) 60%, rgba(9, 24, 42, 0.3) 100%);
}
.tiles--photo .tile svg { margin-bottom: auto; }
.tiles--photo .tile span { padding-right: 42px; }

/* ---------- 19-3. 페이지 헤더 사진 ---------- */
.page-head--photo { background: var(--navy-900); }
.page-head__media { position: absolute; inset: 0; }
.page-head__media img { width: 100%; height: 100%; object-fit: cover; }
.page-head__media::after {
  content: ""; position: absolute; inset: 0;
  background:
    linear-gradient(102deg, rgba(8, 22, 40, 0.93) 0%, rgba(8, 22, 40, 0.78) 46%, rgba(8, 22, 40, 0.42) 100%);
}
.page-head--photo::after { opacity: 0.5; }

/* ---------- 19-4. 섹션 배너 (유닛/프로젝트) ---------- */
.figure {
  position: relative; overflow: hidden;
  margin-bottom: clamp(var(--space-8), 3vw, var(--space-12));
  aspect-ratio: 16 / 7;
  border-radius: var(--radius);
  background: var(--surface-3);
}
.figure img {
  width: 100%; height: 100%; object-fit: cover;
  transform: scale(1.02);
  transition: transform 1s var(--ease);
}
.figure:hover img { transform: scale(1.07); }
.figure__cap {
  position: absolute; left: 0; bottom: 0;
  padding: var(--space-3) var(--space-5);
  font-size: var(--text-xs); letter-spacing: 0.06em; text-transform: uppercase;
  color: #fff; background: linear-gradient(to top, rgba(8, 22, 40, 0.82), transparent);
  width: 100%;
}

/* 사진 + 본문 2단 */
.media-split { display: grid; grid-template-columns: 0.95fr 1.05fr; gap: clamp(var(--space-6), 3vw, var(--space-12)); align-items: start; }
.media-split .figure { aspect-ratio: 3 / 2; margin-bottom: 0; }

/* ---------- 19-5. 풀블리드 사진 밴드 ---------- */
.band {
  position: relative; overflow: hidden;
  min-height: clamp(300px, 42vw, 460px);
  display: flex; align-items: center;
  background: var(--navy-900); color: #fff;
}
.band__media { position: absolute; inset: 0; }
.band__media img {
  width: 100%; height: 100%; object-fit: cover;
  transform: scale(1.14);
  will-change: transform;
}
.band__media::after {
  content: ""; position: absolute; inset: 0;
  background:
    linear-gradient(96deg, rgba(8, 22, 40, 0.90) 0%, rgba(8, 22, 40, 0.68) 48%, rgba(8, 22, 40, 0.42) 100%),
    linear-gradient(to top, rgba(8, 22, 40, 0.78) 0%, rgba(8, 22, 40, 0.20) 55%, transparent 100%);
}
.band .wrap { position: relative; z-index: 1; padding-block: clamp(var(--space-10), 5vw, var(--space-16)); }
.band .eyebrow { color: #6fd0f5; }
.band h2 { margin-top: var(--space-3); font-size: var(--text-xl); font-weight: 800; letter-spacing: -0.01em; }
.band p { margin-top: var(--space-4); max-width: 60ch; font-size: var(--text-sm); color: rgba(255, 255, 255, 0.80); }
.band__stats {
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-6); margin-top: clamp(var(--space-8), 3vw, var(--space-10));
  padding-top: var(--space-6); border-top: 1px solid rgba(255, 255, 255, 0.22);
}
.band__stats b { display: block; font-size: var(--text-lg); font-weight: 800; color: #fff; }
.band__stats span { font-size: var(--text-xs); color: rgba(255, 255, 255, 0.66); }

/* ---------- 19-6. 모션 디테일 ---------- */
.rv { transition-delay: var(--d, 0s); }
.tabs { position: sticky; top: 0; z-index: 40; transition: box-shadow 0.25s var(--ease); }
.tabs.is-stuck { box-shadow: 0 6px 20px rgba(16, 32, 51, 0.10); }
.nav-link { position: relative; }
.card { transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease), border-color 0.3s; }
.card:hover { transform: translateY(-3px); }

@media (prefers-reduced-motion: reduce) {
  .hero--photo .hero__media img { animation: none; transform: none; }
  .band__media img { transform: none; }
  .figure img, .tiles--photo .tile__media img { transition: none; }
  .card:hover { transform: none; }
}

/* ---------- 19-7. 사진 요소 반응형 ---------- */
@media (max-width: 1119px) {
  .tabs { top: var(--topbar-h); }
  .hero--photo { min-height: clamp(440px, 68vh, 620px); }
}
@media (max-width: 1023px) {
  .tiles--photo { grid-template-columns: repeat(2, 1fr); }
  .tiles--photo .tile { min-height: 230px; }
  .tiles--photo .tile:nth-child(2n) { border-right: 0; }
  .tiles--photo .tile:nth-child(-n+2) { border-bottom: 1px solid rgba(255, 255, 255, 0.10); }
}
@media (max-width: 860px) {
  .media-split { grid-template-columns: 1fr; }
  .band__stats { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 719px) {
  .hero--photo { min-height: 460px; padding-block: var(--space-16) var(--space-10); }
  .tiles--photo { grid-template-columns: 1fr; }
  .tiles--photo .tile { min-height: 190px; border-right: 0; border-bottom: 1px solid rgba(255, 255, 255, 0.10); }
  .figure { aspect-ratio: 16 / 9; }
  .band { min-height: 280px; }
}

/* ==========================================================================
   20. 회사 로고 (Illustrator SVG 원본)
   ========================================================================== */
.brand-logo {
  display: block;
  width: 176px;
  height: auto;
  max-width: 100%;
}
.side__brand { padding: var(--space-6) var(--space-6) var(--space-5); }
.topbar__brand .brand-logo { width: 128px; }
.footer__brand { margin-bottom: var(--space-4); }
.footer__brand .brand-logo { width: 168px; }
.footer__tag {
  display: block;
  margin-top: var(--space-2);
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.62);
}

/* 회사소개 – 그룹 CI */
.ci {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-4);
  margin-top: clamp(var(--space-8), 4vw, var(--space-12));
}
.ci__box {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-4);
  min-height: 172px;
  padding: var(--space-6);
  border: 1px solid var(--line);
  background: #fff;
}
.ci__box img { width: 176px; height: auto; }
.ci__box--dark { background: var(--navy-900); border-color: var(--navy-900); }
.ci__box--mark img { width: 56px; }
.ci__cap {
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.ci__box--dark .ci__cap { color: rgba(255, 255, 255, 0.66); }

@media (max-width: 860px) {
  .ci { grid-template-columns: 1fr 1fr; }
  .ci__box--mark { grid-column: span 2; }
}
@media (max-width: 519px) {
  .ci { grid-template-columns: 1fr; }
  .ci__box--mark { grid-column: auto; }
  .ci__box { min-height: 144px; }
}
.topbar__brand .brand-logo--sym { display: none; }
@media (max-width: 419px) {
  .topbar__brand .brand-logo { width: 112px; }
}
@media (max-width: 359px) {
  .topbar__brand .brand-logo { display: none; }
  .topbar__brand .brand-logo--sym { display: block; width: 26px; }
}

/* ============================================================
   21. 로고 색상 전환 · 모바일 드로어 중복 로고 제거
   ============================================================ */
/* 브라우저 자동 다크모드(안드로이드 크롬 등)가 배경만 어둡게 바꿔
   검정 로고가 탈색되어 보이는 문제를 방지 */
:root { color-scheme: only light; }

/* 기본(밝은 배경)에서는 검정 로고만 노출 */
.brand-logo--dk { display: none; }

/* 브라우저가 강제로 어둡게 바꾸는 경우까지 대비해, 상단바·사이드바를
   확실한 흰색으로 고정하고 로고는 검정 버전을 유지 */
.topbar, .side { forced-color-adjust: none; }
.topbar { background: #fff; }
.side { background: #fff; }

/* 어두운 배경(푸터·CI 반전 박스)에서만 흰색 로고 사용 */
@media (prefers-color-scheme: dark) {
  .topbar__brand .brand-logo--dk,
  .side__brand .brand-logo--dk { display: none; }
}

/* 모바일·태블릿: 상단바에 이미 로고가 고정되어 있으므로
   메뉴(드로어)를 열었을 때 나오는 로고는 숨김 */
@media (max-width: 1119px) {
  .side__brand { display: none; }
  .side { padding-top: var(--topbar-h); }
}

/* 아주 좁은 화면: 글자 로고 대신 심볼만 */
@media (max-width: 359px) {
  .topbar__brand .brand-logo--lt,
  .topbar__brand .brand-logo--dk { display: none; }
  .topbar__brand .brand-logo--sym { display: block; width: 26px; }
}

/* ============================================================
   22. 데스크톱(1120px 이상) 전용 본문 확대 · 제목 윤곽 강화
   - 모바일·태블릿 크기는 그대로 유지하고 PC 에서만 2px 크게
   ============================================================ */
@media (min-width: 1120px) {
  :root {
    --text-xs: 1rem;          /* 14px → 16px */
    --text-sm: 1.125rem;      /* 16px → 18px */
    --text-base: 1.1875rem;   /* 17px → 19px */
    --text-lg: 1.625rem;      /* 24px → 26px */
    --text-xl: 2.375rem;      /* 36px → 38px */
    --text-2xl: 3.375rem;     /* 52px → 54px */
  }
  .footer__tag, .ci__cap, .figure__cap { font-size: 0.8125rem; }
  .lang-switch button, .nav-item > a, .nav-item > button { font-size: var(--text-sm); }
  .lead { max-width: 60ch; }
}

/* 제목 윤곽 강화 — 자간을 좁히고 줄 균형을 맞춰 형태가 또렷하게 보이도록 */
.hero h1, .h-sec, .h-card, .band h2 {
  text-wrap: balance;
  font-synthesis: none;
}
.hero h1 { font-weight: 800; letter-spacing: -0.026em; }
.h-sec { font-weight: 800; letter-spacing: -0.022em; }
.h-card { letter-spacing: -0.012em; }
/* 사진 위에 놓이는 제목은 옅은 그림자로 배경과 분리 */
.hero--photo h1, .band h2 { text-shadow: 0 1px 2px rgba(4, 12, 24, 0.32), 0 10px 30px rgba(4, 12, 24, 0.28); }
.hero--photo .hero__sub, .band .wrap > p { text-shadow: 0 1px 2px rgba(4, 12, 24, 0.30); }
.section--dark .h-sec { text-shadow: 0 1px 2px rgba(0, 0, 0, 0.28); }

/* ---------- 23. 밝은 배경 섹션 (수소 순환경제) ------------------------- */
/* 흰 배경 + 검은 글씨. 위쪽 섹션과 구분되도록 얇은 경계선만 사용 */
.section--divide { background: var(--surface); color: var(--ink); border-top: 1px solid var(--line); }
.section--divide .h-sec,
.section--divide .h-card { color: var(--navy-900); text-shadow: none; }
.section--divide .lead,
.section--divide p,
.section--divide li { color: var(--ink-2); }
.section--divide .eyebrow { color: var(--accent); }
/* 흰 배경 위 카드는 테두리로 구획 */
.card--line { background: var(--surface); border-color: var(--line-2); }
.card--line .h-card { color: var(--navy-900); }
.card--line p { color: var(--ink-2); }

/* ---------- 24. 줄바꿈 정리 (중국어·일본어 고아 글자 방지) ---------- */
/* 마지막 몇 글자를 한 덩어리로 묶어 한두 글자만 남는 줄을 없앤다 (main.js §14) */
.tw-keep { white-space: nowrap; }
/* 브라우저가 지원하면 짧은 마지막 줄을 스스로 피하도록 한다 */
html[lang="zh"] p[data-lang], html[lang="ja"] p[data-lang],
html[lang="zh"] li[data-lang], html[lang="ja"] li[data-lang],
html[lang="zh"] dd[data-lang], html[lang="ja"] dd[data-lang] {
  text-wrap: pretty;
  line-break: strict;
  overflow-wrap: normal;
}

/* 아주 좁은 화면(≤359px)에서는 히어로 제목을 조금 줄여 어절이 깔끔하게 나뉘도록 */
@media (max-width: 359px) {
  .hero h1 { font-size: 1.5rem; line-height: 1.32; }
}