/* ============================================
   Mobai 사이트 공통 CSS
   ============================================ */

* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --navy: #1E3A5F;
  --navy-deep: #122849;
  --navy-darker: #0B1B33;
  --navy-light: #2D4B6F;
  --navy-pale: #E8EDF3;
  --navy-soft: #F4F7FA;

  --gray-900: #111827;
  --gray-700: #374151;
  --gray-500: #6B7280;
  --gray-400: #9CA3AF;
  --gray-300: #D1D5DB;
  --gray-200: #E5E7EB;
  --gray-100: #F3F4F6;
  --gray-50: #F9FAFB;
  --white: #FFFFFF;
  --max-width: 1200px;
}

html { scroll-behavior: smooth; }
body {
  font-family: 'Pretendard', 'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  color: var(--gray-900);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  background: var(--white);
  word-break: keep-all;
  overflow-wrap: break-word;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 72px;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--gray-100);
  z-index: 100;
  transition: all .3s ease;
}
.header__inner {
  max-width: var(--max-width);
  height: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  display: flex;
  align-items: center;
  gap: 4px;
  font-weight: 800;
  font-size: 26px;
  letter-spacing: -.02em;
  color: var(--gray-900);
}
.logo__img {
  height: 40px;
  width: auto;
  display: block;
}
/* 어두운 배경에서는 로고를 흰색으로 반전 */
.footer .logo__img {
  filter: brightness(0) invert(1);
  height: 36px;
}
.logo__sub {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .15em;
  color: var(--gray-500);
  text-transform: uppercase;
}
.nav {
  display: flex;
  gap: 40px;
  align-items: center;
}
.nav > a,
.nav-item__link {
  font-size: 15px;
  font-weight: 500;
  color: var(--gray-700);
  transition: color .2s;
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.nav > a:hover,
.nav-item:hover .nav-item__link { color: var(--navy); }
.nav > a.active,
.nav-item__link.active { color: var(--navy); font-weight: 600; }
.nav > a::after,
.nav-item__link::after {
  content: '';
  position: absolute;
  left: 0; bottom: -8px;
  width: 0; height: 2px;
  background: var(--navy);
  transition: width .3s ease;
}
.nav > a:hover::after,
.nav > a.active::after,
.nav-item:hover .nav-item__link::after,
.nav-item__link.active::after { width: 100%; }

/* ===== Nav Dropdown ===== */
.nav-item {
  position: relative;
}
.nav-item__caret {
  transition: transform .2s ease;
  margin-top: 1px;
}
.nav-item:hover .nav-item__caret { transform: rotate(180deg); }

.nav-dropdown {
  position: absolute;
  top: 100%;
  left: -20px;
  margin-top: 14px;
  min-width: 340px;
  background: var(--white);
  border: 1px solid var(--gray-100);
  border-radius: 14px;
  padding: 12px;
  box-shadow: 0 16px 40px rgba(0,0,0,.08);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px);
  transition: opacity .2s ease, visibility .2s ease, transform .2s ease;
  pointer-events: none;
  z-index: 110;
}
/* invisible bridge to prevent hover gap */
.nav-dropdown::before {
  content: '';
  position: absolute;
  top: -14px; left: 0; right: 0;
  height: 14px;
}
.nav-item:hover .nav-dropdown,
.nav-item:focus-within .nav-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  pointer-events: auto;
}
.nav-dropdown a {
  display: block;
  padding: 14px 16px;
  border-radius: 10px;
  transition: background .2s ease;
}
.nav-dropdown a:hover { background: var(--navy-soft); }
.nav-dropdown a::after { display: none; }
.nav-dropdown__title {
  display: block;
  font-size: 15px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 4px;
  letter-spacing: -.01em;
}
.nav-dropdown a:hover .nav-dropdown__title { color: var(--navy); }
.nav-dropdown__desc {
  display: block;
  font-size: 13px;
  color: var(--gray-500);
  line-height: 1.4;
}

.lang-toggle {
  padding: 8px 14px;
  background: var(--navy);
  color: var(--white);
  font-size: 13px;
  font-weight: 600;
  border-radius: 6px;
  letter-spacing: .05em;
  transition: background .2s;
}
.lang-toggle:hover { background: var(--navy-deep); }

.menu-btn {
  display: none;
  width: 32px; height: 32px;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
}
.menu-btn span {
  display: block;
  width: 24px; height: 2px;
  background: var(--gray-900);
  transition: all .3s;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 16px 28px;
  font-size: 15px;
  font-weight: 600;
  border-radius: 8px;
  transition: all .25s ease;
  letter-spacing: -.01em;
}
.btn--primary {
  background: var(--white);
  color: var(--navy-deep);
}
.btn--primary:hover {
  background: var(--navy-pale);
  transform: translateY(-2px);
  box-shadow: 0 12px 24px rgba(0,0,0,.25);
}
.btn--ghost {
  background: rgba(255,255,255,.06);
  color: var(--white);
  border: 1px solid rgba(255,255,255,.3);
  backdrop-filter: blur(8px);
}
.btn--ghost:hover {
  background: rgba(255,255,255,.14);
  border-color: rgba(255,255,255,.5);
}
.btn--navy {
  background: var(--navy);
  color: var(--white);
}
.btn--navy:hover {
  background: var(--navy-deep);
  transform: translateY(-2px);
  box-shadow: 0 12px 24px rgba(18,40,73,.25);
}
.btn--outline {
  background: transparent;
  color: var(--navy);
  border: 1.5px solid var(--navy);
}
.btn--outline:hover {
  background: var(--navy);
  color: var(--white);
  transform: translateY(-2px);
}

/* ===== Section common ===== */
section { padding: 120px 24px; }
.container {
  max-width: var(--max-width);
  margin: 0 auto;
}
.section__label {
  display: block;
  width: fit-content;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .2em;
  color: var(--navy);
  text-transform: uppercase;
  margin: 0 auto 16px;
}
.section__label::before {
  content: '';
  display: inline-block;
  width: 24px; height: 1px;
  background: var(--navy);
  vertical-align: middle;
  margin-right: 12px;
  margin-top: -2px;
}
.section__title {
  font-size: clamp(28px, 3.5vw, 44px);
  font-weight: 800;
  letter-spacing: -.03em;
  line-height: 1.25;
  margin-bottom: 10px;
  color: var(--gray-900);
  text-align: center;
}
.section__desc {
  font-size: 17px;
  color: var(--gray-500);
  max-width: 720px;
  line-height: 1.7;
  text-align: center;
  margin-left: auto;
  margin-right: auto;
}

/* ===== Footer ===== */
.footer {
  background: var(--navy-darker);
  color: rgba(255,255,255,.6);
  padding: 80px 24px 40px;
}
.footer__inner {
  max-width: var(--max-width);
  margin: 0 auto;
}
.footer__top {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 64px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255,255,255,.08);
  margin-bottom: 40px;
}
.footer__brand .logo { color: var(--white); margin-bottom: 16px; }
.footer__brand p { font-size: 14px; line-height: 1.7; }
.footer__cols {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 40px;
}
.footer__col h4 {
  font-size: 12px;
  font-weight: 700;
  color: var(--white);
  letter-spacing: .15em;
  text-transform: uppercase;
  margin-bottom: 20px;
}
.footer__col ul { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.footer__col li { font-size: 14px; line-height: 1.6; }
.footer__col a:hover { color: var(--white); }
.footer__bottom {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: rgba(255,255,255,.4);
}

/* ===== Reveal animation ===== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .8s ease, transform .8s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Page Hero (sub-pages) ===== */
.page-hero {
  position: relative;
  padding: 200px 24px 100px;
  background: linear-gradient(135deg, var(--navy-darker) 0%, var(--navy-deep) 50%, var(--navy) 100%);
  color: var(--white);
  overflow: hidden;
}
.page-hero::before {
  content: '';
  position: absolute;
  top: -200px; right: -200px;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(45,75,111,.4), transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}
.page-hero::after {
  content: '';
  position: absolute;
  bottom: -300px; left: -200px;
  width: 800px; height: 800px;
  background: radial-gradient(circle, rgba(30,58,95,.5), transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}
.page-hero__inner {
  position: relative;
  z-index: 2;
}
.page-hero a, .page-hero button {
  position: relative;
  z-index: 3;
}
.page-hero__inner {
  position: relative;
  max-width: var(--max-width);
  margin: 0 auto;
}
.page-hero__breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: rgba(255,255,255,.5);
  margin-bottom: 24px;
  font-weight: 500;
}
.page-hero__breadcrumb a:hover { color: var(--white); }
.page-hero__breadcrumb .sep { opacity: .5; }
.page-hero__label {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .2em;
  color: rgba(255,255,255,.65);
  text-transform: uppercase;
  margin-bottom: 16px;
}
.page-hero__label::before {
  content: '';
  display: inline-block;
  width: 24px; height: 1px;
  background: rgba(255,255,255,.65);
  vertical-align: middle;
  margin-right: 12px;
  margin-top: -2px;
}
.page-hero h1 {
  font-size: clamp(32px, 5vw, 56px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -.03em;
  margin-bottom: 20px;
  max-width: 900px;
}
.page-hero h1.page-hero__brand {
  font-size: clamp(44px, 6.5vw, 80px);
  font-weight: 800;
  line-height: .95;
  letter-spacing: -.045em;
  margin-bottom: 0;
}
.page-hero__brand-full {
  font-size: clamp(14px, 1.3vw, 18px);
  font-weight: 500;
  letter-spacing: .08em;
  color: rgba(255,255,255,.68);
  margin: 2px 0 22px;
}
.page-hero__tagline {
  font-size: clamp(20px, 2.2vw, 28px);
  font-weight: 600;
  line-height: 1.4;
  letter-spacing: -.015em;
  color: rgba(255,255,255,.92);
  max-width: 820px;
  margin-bottom: 28px;
}
.page-hero__sub {
  font-size: clamp(16px, 1.5vw, 19px);
  color: rgba(255,255,255,.78);
  line-height: 1.7;
  max-width: 1100px;
  margin-bottom: 40px;
  font-weight: 300;
}
.page-hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ===== Solution Tabs ===== */
.sol-tabs {
  background: var(--white);
  border-bottom: 1px solid var(--gray-100);
  position: sticky;
  top: 72px;
  z-index: 50;
  backdrop-filter: blur(12px);
}
.sol-tabs__inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  gap: 0;
}
.sol-tabs a {
  flex: 1;
  text-align: center;
  padding: 20px 16px;
  font-size: 15px;
  font-weight: 600;
  color: var(--gray-500);
  border-bottom: 2px solid transparent;
  transition: all .25s ease;
  letter-spacing: -.01em;
}
.sol-tabs a:hover { color: var(--navy); }
.sol-tabs a.active {
  color: var(--navy);
  border-bottom-color: var(--navy);
}

/* ===== Generic content blocks ===== */
.section-light { background: var(--white); }
.section-soft { background: var(--navy-soft); }
.section-dark { background: var(--navy-darker); color: var(--white); }
.section-dark .section__title { color: var(--white); }
.section-dark .section__desc { color: rgba(255,255,255,.6); }
.section-dark .section__label { color: rgba(255,255,255,.7); }
.section-dark .section__label::before { background: rgba(255,255,255,.7); }

/* ===== Feature Grid ===== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 64px;
}
.feature-card {
  padding: 40px 32px;
  background: var(--white);
  border: 1px solid var(--gray-100);
  border-radius: 16px;
  transition: all .35s ease;
  position: relative;
}
.feature-card:hover {
  border-color: var(--navy);
  transform: translateY(-6px);
  box-shadow: 0 20px 50px rgba(18,40,73,.08);
}
.feature-card__icon {
  width: 56px; height: 56px;
  background: var(--navy-pale);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  color: var(--navy);
}
.feature-card__title {
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -.02em;
  margin-bottom: 12px;
  color: var(--gray-900);
}
.feature-card__desc {
  font-size: 15px;
  color: var(--gray-500);
  line-height: 1.7;
}

/* dark variant */
.section-dark .feature-card {
  background: rgba(255,255,255,.04);
  border-color: rgba(255,255,255,.1);
}
.section-dark .feature-card:hover {
  border-color: rgba(255,255,255,.3);
  background: rgba(255,255,255,.08);
}
.section-dark .feature-card__icon {
  background: rgba(255,255,255,.08);
  color: var(--white);
}
.section-dark .feature-card__title { color: var(--white); }
.section-dark .feature-card__desc { color: rgba(255,255,255,.7); }

/* ===== Spec list ===== */
.spec-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 32px;
  margin-top: 56px;
}
.spec-item {
  text-align: center;
  padding: 24px;
}
.spec-item__num {
  font-family: 'Inter', sans-serif;
  font-size: clamp(40px, 4.5vw, 56px);
  font-weight: 800;
  color: var(--navy);
  letter-spacing: -.03em;
  line-height: 1;
  margin-bottom: 8px;
}
.spec-item__label {
  font-size: 14px;
  color: var(--gray-500);
  font-weight: 500;
}
.section-dark .spec-item__num {
  background: linear-gradient(135deg, #fff 0%, rgba(255,255,255,.7) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.section-dark .spec-item__label { color: rgba(255,255,255,.6); }

/* ===== Use case list ===== */
.use-case-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 64px;
}
.use-case {
  padding: 32px;
  background: var(--white);
  border: 1px solid var(--gray-100);
  border-radius: 16px;
  display: flex;
  align-items: flex-start;
  gap: 20px;
  transition: all .3s ease;
}
.use-case:hover {
  border-color: var(--navy);
  box-shadow: 0 12px 32px rgba(18,40,73,.06);
}
.use-case__icon {
  width: 48px; height: 48px;
  background: var(--navy);
  color: var(--white);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.use-case__title {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--gray-900);
}
.use-case__desc {
  font-size: 14px;
  color: var(--gray-500);
  line-height: 1.6;
}

/* ===== Step process ===== */
.process {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  margin-top: 64px;
  position: relative;
}
.process::before {
  content: '';
  position: absolute;
  top: 28px;
  left: 10%; right: 10%;
  height: 2px;
  background: linear-gradient(90deg, var(--navy-pale), var(--navy), var(--navy-pale));
}
.process-step {
  background: var(--white);
  padding: 40px 24px 32px;
  border-radius: 16px;
  border: 1px solid var(--gray-100);
  text-align: center;
  position: relative;
  transition: all .3s ease;
}
.process-step:hover {
  border-color: var(--navy);
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(18,40,73,.08);
}
.process-step__num {
  width: 56px; height: 56px;
  background: var(--navy);
  color: var(--white);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 24px;
  font-family: 'Inter', sans-serif;
  font-weight: 800;
  font-size: 20px;
}
.process-step__title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--gray-900);
}
.process-step__desc {
  font-size: 14px;
  color: var(--gray-500);
  line-height: 1.65;
}

/* ===== Reference list ===== */
.ref-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin-top: 48px;
}
.ref-item {
  padding: 24px;
  background: var(--white);
  border: 1px solid var(--gray-100);
  border-radius: 12px;
  display: flex;
  align-items: center;
  gap: 14px;
  transition: all .3s ease;
}
.ref-item:hover {
  border-color: var(--navy);
  background: var(--navy-soft);
}
.ref-item__icon {
  width: 40px; height: 40px;
  background: var(--navy-pale);
  color: var(--navy);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.ref-item__name {
  font-size: 15px;
  font-weight: 600;
  color: var(--gray-900);
}
.ref-item__sub {
  font-size: 13px;
  color: var(--gray-500);
  margin-top: 2px;
}

/* ===== CTA Section ===== */
.cta {
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-deep) 60%, var(--navy-darker) 100%);
  color: var(--white);
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta::before {
  content: '';
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 700px; height: 700px;
  background: radial-gradient(circle, rgba(255,255,255,.05), transparent 70%);
  border-radius: 50%;
}
.cta .section__label { color: rgba(255,255,255,.75); }
.cta .section__label::before { background: rgba(255,255,255,.75); }
.cta__inner {
  position: relative;
  max-width: 1100px;
  margin: 0 auto;
}
.cta h2 {
  font-size: clamp(26px, 3vw, 36px);
  font-weight: 800;
  line-height: 1.4;
  letter-spacing: -.03em;
  margin-bottom: 24px;
}
.cta p {
  font-size: 17px;
  color: rgba(255,255,255,.72);
  margin-bottom: 40px;
  line-height: 1.7;
}

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .nav, .lang-toggle { display: none; }
  .menu-btn { display: flex; }
  section { padding: 80px 20px; }
  .page-hero { padding: 140px 20px 60px; }
  .footer__top { grid-template-columns: 1fr; gap: 40px; }
  .footer__cols { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr; }
  .use-case-grid { grid-template-columns: 1fr; }
  .process { grid-template-columns: 1fr; gap: 16px; }
  .process::before { display: none; }
  .sol-tabs__inner { overflow-x: auto; }
  .sol-tabs a { white-space: nowrap; min-width: 120px; }

  .nav.open {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    position: fixed;
    top: 72px; left: 0; right: 0;
    background: var(--white);
    padding: 24px;
    gap: 20px;
    border-bottom: 1px solid var(--gray-100);
    box-shadow: 0 12px 32px rgba(0,0,0,.08);
    max-height: calc(100vh - 72px);
    overflow-y: auto;
  }
  .nav.open .lang-toggle { display: inline-flex; align-self: flex-start; }

  /* Mobile dropdown — show inline */
  .nav-item { width: 100%; }
  .nav-item__caret { display: none; }
  .nav-dropdown {
    position: static;
    margin: 12px 0 0 12px;
    min-width: auto;
    width: 100%;
    box-shadow: none;
    border: none;
    padding: 0;
    opacity: 1;
    visibility: visible;
    transform: none;
    pointer-events: auto;
    background: transparent;
  }
  .nav-dropdown::before { display: none; }
  .nav-dropdown a { padding: 10px 12px; border-left: 2px solid var(--gray-100); border-radius: 0; }
  .nav-dropdown a:hover { border-left-color: var(--navy); background: var(--navy-soft); }
}