/* ============================================================
   INVISIONLAB refine.css — 디자인 정제 레이어
   기존 CSS 파일을 수정하지 않고 마지막에 로드되어 덮어쓴다.
   롤백은 index.html 복원만으로 완료된다.
   ============================================================ */

:root {
  /* 다크 베이스 */
  --ink-950: #06070d;
  --ink-900: #0b0e17;
  --ink-800: #141927;
  --line-dark: rgba(255, 255, 255, .10);
  /* 텍스트 (다크 위) */
  --tx-hi: #f4f6fb;
  --tx-mid: #b9c0d0;
  --tx-low: #7d8598;
  /* 포인트 컬러 — 기존 --bs-info / --bs-secondary 승계 */
  --accent: #5dc3ff;
  --accent-deep: #1f1e92;
  --accent-soft: rgba(93, 195, 255, .12);
  /* 라이트 밴드 (History / Certificate) */
  --paper: #f7f8fa;
  --tx-dark: #1a1d26;
  --tx-dark-mid: #4a4f5e;
  --line-light: #e3e6ec;
  /* 타이포 스케일 */
  --fs-hero: clamp(2.6rem, 5.5vw, 4.4rem);
  --fs-h1: clamp(2rem, 3.5vw, 3rem);
  --fs-h2: clamp(1.5rem, 2.4vw, 2rem);
  --fs-lead: clamp(1.05rem, 1.4vw, 1.25rem);
  /* 리듬 */
  --sec-pad: clamp(96px, 12vw, 160px);
  --radius: 14px;
}

/* ---------- 베이스 ---------- */

html {
  scroll-behavior: smooth;
}

body {
  background: var(--ink-950);
}

#aboutus,
#leadership,
#product,
#contactus {
  scroll-margin-top: 88px;
}

p,
li {
  word-break: keep-all;
}

::selection {
  background: var(--accent);
  color: #06070d;
}

/* 스크롤바 — 기존 그라디언트를 브랜드 톤으로 통일 */
::-webkit-scrollbar-track {
  background: var(--ink-900);
}

::-webkit-scrollbar-thumb {
  background: linear-gradient(45deg, #1f1e92, #5dc3ff);
}

::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(45deg, #191875, #44b7f5);
}

/* ---------- 공통 컴포넌트 ---------- */

.eyebrow {
  font-size: .875rem;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: .9rem;
}

.sec-title {
  font-size: var(--fs-h1);
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1.18;
}

.sec-lead {
  font-size: var(--fs-lead);
  font-weight: 300;
  color: var(--tx-mid);
  line-height: 1.75;
  max-width: 560px;
  margin-top: 1.1rem;
}

.btn-accent {
  --bs-btn-color: #06070d;
  --bs-btn-bg: var(--accent);
  --bs-btn-border-color: var(--accent);
  --bs-btn-hover-color: #06070d;
  --bs-btn-hover-bg: #7dcfff;
  --bs-btn-hover-border-color: #7dcfff;
  --bs-btn-active-color: #06070d;
  --bs-btn-active-bg: #8ed5ff;
  --bs-btn-active-border-color: #8ed5ff;
  --bs-btn-font-weight: 700;
  border-radius: 999px;
}

.btn-ghost {
  --bs-btn-color: var(--tx-hi);
  --bs-btn-bg: transparent;
  --bs-btn-border-color: rgba(255, 255, 255, .45);
  --bs-btn-hover-color: #06070d;
  --bs-btn-hover-bg: var(--tx-hi);
  --bs-btn-hover-border-color: var(--tx-hi);
  --bs-btn-active-color: #06070d;
  --bs-btn-active-bg: var(--tx-hi);
  --bs-btn-active-border-color: var(--tx-hi);
  --bs-btn-font-weight: 600;
  border-radius: 999px;
}

/* ---------- 네비게이션 ---------- */

.navbar-refined {
  height: 80px;
  background: rgba(6, 7, 13, .82);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line-dark);
}

.navbar-refined .nav-link {
  color: #c9cfdc;
  font-size: 1rem;
  font-weight: 500;
  letter-spacing: .01em;
  padding: .5rem 1rem;
}

.navbar-refined .nav-link:hover,
.navbar-refined .nav-link:focus {
  color: var(--accent);
}

.navbar-refined .btn-demo {
  border: 1px solid rgba(93, 195, 255, .6);
  border-radius: 999px;
  padding: .45rem 1.5rem;
  color: var(--accent);
  font-weight: 600;
  transition: background .2s ease, color .2s ease, border-color .2s ease;
}

.navbar-refined .btn-demo:hover,
.navbar-refined .btn-demo:focus {
  background: var(--accent);
  color: #06070d;
  border-color: var(--accent);
}

/* 모바일 콜랩스 — styles.css / Footer-Dark-icons.css 의 #212529 패널을 덮어씀 */
@media (max-width: 767.98px) {
  .navbar-refined .navbar-collapse {
    background-color: var(--ink-900);
    border: 1px solid var(--line-dark);
    border-radius: var(--radius);
    padding: 16px 24px;
    margin: 8px 0 0 0;
  }
}

/* 768px 이상(메뉴 펼침 상태)에서는 styles.css의 768px 패널 스타일을 무효화 */
@media (min-width: 768px) {
  .navbar-refined .navbar-collapse {
    background-color: transparent;
    border: 0;
    padding: 0;
    margin: 0;
  }
}

/* ---------- 히어로 ---------- */

.video-parallax-container {
  position: relative;
}

/* 텍스트 섀도 대신 스크림으로 가독성 확보 */
.video-parallax-container::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(6, 7, 13, .50) 0%, rgba(6, 7, 13, .22) 45%, rgba(6, 7, 13, .82) 100%);
  pointer-events: none;
}

.video-parallax-container .maxwidth1000 {
  position: relative;
  z-index: 1;
}

.filter {
  filter: brightness(.5) saturate(.9);
}

.hero-title {
  font-size: var(--fs-hero);
  font-weight: 700;
  letter-spacing: -.02em;
  line-height: 1.12;
  margin: 52px 0;
}

.hero-sub {
  font-size: clamp(1.15rem, 1.8vw, 1.5rem);
  font-weight: 400;
  color: var(--tx-hi);
  line-height: 1.65;
  margin-bottom: 2rem;
}

.hero-cta {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ---------- 숫자 하이라이트 밴드 ---------- */

.stats-band {
  background: var(--ink-950);
  border-bottom: 1px solid var(--line-dark);
  padding: clamp(48px, 7vw, 84px) 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px 24px;
}

.stat {
  text-align: center;
  position: relative;
}

.stat + .stat::before {
  content: "";
  position: absolute;
  left: -12px;
  top: 12%;
  height: 76%;
  width: 1px;
  background: var(--line-dark);
}

.stat-num {
  display: block;
  font-size: clamp(2rem, 3.2vw, 2.9rem);
  font-weight: 700;
  letter-spacing: -.02em;
  color: var(--accent);
  line-height: 1.1;
}

.stat-label {
  display: block;
  margin-top: .6rem;
  font-size: .95rem;
  font-weight: 400;
  color: var(--tx-mid);
  line-height: 1.5;
  word-break: keep-all;
}

@media (max-width: 767.98px) {
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 40px 16px;
  }

  .stat + .stat::before {
    display: none;
  }
}

/* ---------- About 밴드 ---------- */

.about-band {
  background: url("../img/c2_bg.jpg") center / cover no-repeat, var(--ink-900);
}

.about-pad {
  padding: var(--sec-pad) 24px;
}

.philo-gap {
  margin-top: clamp(80px, 10vw, 140px);
}

.wwd-sec {
  margin-top: clamp(100px, 14vw, 200px);
}

.wwd-row {
  margin-top: clamp(56px, 7vw, 96px);
}

.wwd-title {
  font-size: var(--fs-h2);
  font-weight: 600;
  color: var(--tx-hi);
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 1.2rem;
}

.wwd-num {
  font-weight: 700;
  color: var(--accent);
  letter-spacing: .04em;
}

.wwd-desc {
  font-size: var(--fs-lead);
  font-weight: 300;
  color: var(--tx-mid);
  line-height: 1.75;
  max-width: 640px;
}

/* ---------- Leadership ---------- */

.lead-sec {
  padding: clamp(72px, 9vw, 120px) 24px var(--sec-pad);
}

.lead-sec .sec-title {
  margin-bottom: clamp(40px, 5vw, 64px);
}

.name-en {
  display: inline-block;
  margin-left: 14px;
  font-size: .45em;
  font-weight: 500;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--tx-low);
  vertical-align: middle;
}

.lead-photo {
  width: 176px;
  height: 176px;
  border-radius: 50%;
  object-fit: cover;
  object-position: 50% 30%;
  border: 3px solid rgba(93, 195, 255, .35);
  box-shadow: 0 0 0 8px rgba(93, 195, 255, .08);
  display: block;
  margin-bottom: 1.6rem;
}

.lead-subhead {
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--tx-hi);
  margin-bottom: 1rem;
}

.edu-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.edu-list li {
  color: var(--tx-mid);
  font-size: 1rem;
  padding: .45rem 0;
  border-bottom: 1px solid var(--line-dark);
}

.edu-list li:last-child {
  border-bottom: 0;
}

.edu-list li span {
  margin-left: 8px;
  font-size: .85rem;
  color: var(--tx-low);
}

.pubs-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.pubs-head .lead-subhead {
  margin-bottom: 0;
}

.pubs-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 1.7em;
  height: 1.7em;
  margin-left: 10px;
  padding: 0 .35em;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: .9em;
  font-weight: 700;
}

.btn-ghost-sm {
  display: inline-block;
  padding: .4rem 1.1rem;
  border: 1px solid rgba(255, 255, 255, .3);
  border-radius: 999px;
  color: var(--tx-mid);
  font-size: .9rem;
  font-weight: 500;
  text-decoration: none;
  transition: color .2s ease, border-color .2s ease;
}

.btn-ghost-sm:hover,
.btn-ghost-sm:focus {
  color: var(--accent);
  border-color: var(--accent);
}

.pub-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px 20px;
}

.pub-list li {
  background: rgba(20, 25, 39, .55);
  border: 1px solid var(--line-dark);
  border-radius: 10px;
  padding: 12px 16px;
  min-width: 0;
}

.pub-meta {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.pub-journal {
  font-weight: 600;
  font-size: .95rem;
  color: var(--tx-hi);
}

.pub-year {
  font-size: .82rem;
  color: var(--tx-low);
}

.pub-name {
  display: block;
  margin-top: 4px;
  font-size: .875rem;
  color: var(--tx-mid);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

@media (max-width: 991.98px) {
  .pub-list {
    grid-template-columns: 1fr;
  }

  .lead-profile {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    margin-bottom: 2.5rem;
  }
}

/* ---------- Products ---------- */

.prod-sec {
  padding-top: clamp(90px, 11vw, 140px);
  padding-bottom: clamp(90px, 11vw, 140px);
}

.prod-sec .sec-title {
  margin-bottom: clamp(36px, 4vw, 56px);
}

.prod-col {
  padding: 0 12px;
  margin-bottom: 24px;
}

.prod-card {
  position: relative;
  display: block;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line-dark);
  background: var(--ink-800);
  text-decoration: none;
  height: 100%;
  transition: border-color .3s ease;
}

.prod-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform .45s ease;
}

.prod-cap {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 20px 22px;
  background: linear-gradient(180deg, rgba(6, 7, 13, 0) 40%, rgba(6, 7, 13, .55) 68%, rgba(6, 7, 13, .94) 100%);
}

.prod-tag {
  font-size: .78rem;
  font-weight: 600;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: .3rem;
}

.prod-name {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--tx-hi);
  margin-bottom: .4rem;
}

.prod-desc {
  font-size: .95rem;
  color: var(--tx-mid);
  line-height: 1.6;
  margin-bottom: 0;
}

@media (hover: hover) {
  .prod-card:hover {
    border-color: rgba(93, 195, 255, .5);
  }

  .prod-card:hover img,
  a.prod-card:focus-visible img {
    transform: scale(1.04);
  }
}

/* ---------- History ---------- */

.history-band {
  background: var(--paper);
}

.history-side {
  background: var(--ink-950);
  padding: clamp(64px, 8vw, 110px) clamp(24px, 6vw, 80px);
}

@media (min-width: 992px) {
  .history-side-inner {
    position: sticky;
    top: 120px;
  }
}

.history-body {
  padding: clamp(56px, 7vw, 96px) clamp(24px, 5vw, 72px);
}

.tl-row {
  display: grid;
  grid-template-columns: 88px 1fr;
  gap: 20px;
  padding-bottom: clamp(36px, 4vw, 56px);
}

.tl-row:last-child {
  padding-bottom: 0;
}

.tl-year {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent-deep);
  letter-spacing: .02em;
  line-height: 1.4;
}

.tl-items {
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
  border-left: 1px solid var(--line-light);
  position: relative;
}

.tl-items::before {
  content: "";
  position: absolute;
  left: -5.5px;
  top: 8px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent-deep);
  box-shadow: 0 0 0 4px rgba(31, 30, 146, .12);
}

.tl-items li {
  color: var(--tx-dark-mid);
  font-size: 1rem;
  padding: .3rem 0;
}

/* ---------- Certificate ---------- */

.cert-band {
  background: url("../img/c5_bg.jpg") center / cover no-repeat, #ffffff;
}

.cert-sec {
  padding-top: clamp(72px, 9vw, 110px);
  padding-bottom: clamp(72px, 9vw, 110px);
}

.cert-sec .sec-title {
  color: var(--tx-dark);
  margin-bottom: clamp(32px, 4vw, 48px);
}

.cert-row {
  row-gap: 24px;
}

.cert-card {
  margin: 0;
  background: #ffffff;
  border: 1px solid var(--line-light);
  border-radius: var(--radius);
  padding: 18px;
  height: 100%;
  box-shadow: 0 10px 30px rgba(16, 24, 40, .06);
}

.cert-card img {
  width: 100%;
  border-radius: 6px;
  display: block;
}

.cert-card figcaption {
  margin-top: 14px;
  text-align: center;
  font-size: 1rem;
  font-weight: 500;
  color: var(--tx-dark);
}

/* ---------- Footer ---------- */

.footer-refined {
  background: var(--ink-950);
  border-top: 1px solid var(--line-dark);
}

.footer-refined .sec-title {
  margin-bottom: .8rem;
}

.foot-lead {
  color: var(--tx-mid);
  margin-bottom: 1.4rem;
}

.foot-list {
  list-style: none;
  padding: 0;
  margin: 0;
  text-align: left;
}

.foot-list li {
  color: var(--tx-mid);
  font-size: .95rem;
  padding: .22rem 0;
}

.foot-list .foot-company {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--tx-hi);
  padding-bottom: .5rem;
}

.foot-label {
  display: inline-block;
  min-width: 108px;
  color: var(--tx-low);
  font-size: .88rem;
}

.foot-list a {
  color: var(--tx-mid);
  text-decoration: none;
}

.foot-list a:hover {
  color: var(--accent);
}

.foot-line {
  border-bottom: 1px solid var(--line-dark);
  margin: 1.1rem 0;
}

.foot-copy {
  color: var(--tx-low);
  font-size: .85rem;
  margin: 0;
  text-align: left;
}

@media (max-width: 991.98px) {
  .footer-refined .foot-list,
  .footer-refined .foot-line,
  .footer-refined .foot-copy {
    max-width: 460px;
    margin-left: auto;
    margin-right: auto;
  }
}