/* ===== Reset & Base ===== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #0EB39D;
  --primary-dark: #1D5C58;
  --primary-deeper: #0a8a79;
  --primary-light: #e6f7f5;
  --accent: #3EAB6A;
  --accent-light: #97CD6C;
  --dark: #1a1a1a;
  --gray-900: #222222;
  --gray-800: #333333;
  --gray-700: #4a4a4a;
  --gray-600: #666666;
  --gray-500: #888888;
  --gray-400: #aaaaaa;
  --gray-300: #cccccc;
  --gray-200: #e5e5e5;
  --gray-100: #f5f5f5;
  --white: #ffffff;
  --font-ko: 'Noto Sans KR', sans-serif;
  --font-en: 'Inter', sans-serif;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
  --shadow-xl: 0 16px 48px rgba(0,0,0,0.15);
  --radius: 12px;
  --radius-lg: 20px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-ko);
  color: var(--gray-800);
  line-height: 1.7;
  background: var(--white);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition);
}

ul { list-style: none; }

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.hide-mobile {
  display: inline;
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  transition: all var(--transition);
  padding: 20px 0;
}

.header.scrolled {
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow-sm);
  padding: 12px 0;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  height: 72px;
  display: flex;
  align-items: center;
}

.logo img {
  height: 72px;
  width: auto;
}

.logo-white { display: block; }
.logo-default { display: none; }

.header.scrolled .logo-white { display: none; }
.header.scrolled .logo-default { display: block; }

.nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  font-size: 15px;
  font-weight: 500;
  color: rgba(255,255,255,0.9);
  position: relative;
  padding: 4px 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width var(--transition);
}

.nav-link:hover::after { width: 100%; }
.nav-link:hover { color: var(--white); }

.header.scrolled .nav-link {
  color: var(--gray-700);
}

.header.scrolled .nav-link:hover {
  color: var(--primary);
}

.btn-nav-contact {
  background: var(--primary) !important;
  color: var(--white) !important;
  padding: 8px 24px !important;
  border-radius: 100px;
  font-weight: 600 !important;
  font-size: 14px !important;
}

.btn-nav-contact::after { display: none !important; }

.btn-nav-contact:hover {
  background: var(--primary-deeper) !important;
  transform: translateY(-1px);
}

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.hamburger span {
  width: 24px;
  height: 2px;
  background: var(--white);
  transition: all var(--transition);
  border-radius: 2px;
}

.header.scrolled .hamburger span {
  background: var(--gray-800);
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: 100px;
  font-size: 15px;
  font-weight: 600;
  font-family: var(--font-ko);
  transition: all var(--transition);
  cursor: pointer;
  border: 2px solid transparent;
}

.btn-primary {
  background: #10B981;
  color: var(--white);
}

.btn-primary:hover {
  background: #059669;
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(16,185,129,0.4);
}

.btn-outline {
  border-color: rgba(255,255,255,0.5);
  color: var(--white);
  background: transparent;
}

.btn-outline:hover {
  border-color: var(--white);
  background: rgba(255,255,255,0.1);
}

.btn-white {
  background: var(--white);
  color: var(--primary-dark);
}

.btn-white:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(255,255,255,0.3);
}

.btn-outline-white {
  border-color: rgba(255,255,255,0.5);
  color: var(--white);
  background: transparent;
}

.btn-outline-white:hover {
  border-color: var(--white);
  background: rgba(255,255,255,0.1);
}

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform: scale(1.05);
  animation: heroZoom 20s ease-in-out infinite alternate;
}

@keyframes heroZoom {
  0% { transform: scale(1.05); }
  100% { transform: scale(1.15); }
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(10,30,28,0.88) 0%,
    rgba(10,50,45,0.75) 50%,
    rgba(10,30,28,0.85) 100%
  );
}

.hero-content {
  position: relative;
  z-index: 1;
  color: var(--white);
  padding-top: 180px;
  padding-bottom: 100px;
  display: grid;
  grid-template-columns: 1fr 420px;
  grid-template-rows: auto auto auto 1fr;
  gap: 0 56px;
  align-items: start;
}

.hero-label {
  font-family: var(--font-en);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: #7EECD8;
  margin-bottom: 20px;
  opacity: 0;
  animation: fadeUp 0.8s ease forwards 0.3s;
}

.hero-title {
  font-size: clamp(32px, 5vw, 56px);
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 24px;
  letter-spacing: -1px;
  opacity: 0;
  animation: fadeUp 0.8s ease forwards 0.5s;
}

.hero-desc {
  font-size: clamp(15px, 1.8vw, 18px);
  line-height: 1.8;
  color: rgba(255,255,255,0.85);
  margin-bottom: 0;
  max-width: 640px;
  opacity: 0;
  animation: fadeUp 0.8s ease forwards 0.7s;
  grid-column: 1;
}

/* Hero Notice Box */
.hero-notice {
  grid-column: 2;
  grid-row: 1 / 5;
  background: rgba(255,255,255,0.1);
  backdrop-filter: blur(16px);
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: var(--radius-lg);
  overflow: hidden;
  opacity: 0;
  animation: fadeUp 0.8s ease forwards 0.9s;
  align-self: center;
  box-shadow: 0 8px 32px rgba(0,0,0,0.15);
}

.hero-notice-tabs {
  display: flex;
  border-bottom: 1px solid rgba(255,255,255,0.12);
}

.hero-tab {
  flex: 1;
  padding: 18px 24px;
  background: none;
  border: none;
  color: rgba(255,255,255,0.45);
  font-size: 15px;
  font-weight: 600;
  font-family: var(--font-ko);
  cursor: pointer;
  transition: all var(--transition);
  position: relative;
}

.hero-tab.active {
  color: var(--white);
  background: rgba(255,255,255,0.06);
}

.hero-tab.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 24px;
  right: 24px;
  height: 2px;
  background: #7EECD8;
  border-radius: 2px 2px 0 0;
}

.hero-tab:hover { color: rgba(255,255,255,0.75); }

.hero-notice-more {
  display: flex;
  align-items: center;
  padding: 0 20px;
  font-size: 13px;
  font-weight: 500;
  color: rgba(255,255,255,0.4);
  margin-left: auto;
  white-space: nowrap;
  transition: color var(--transition);
}

.hero-notice-more:hover { color: #7EECD8; }

.hero-tab-content {
  display: none;
  padding: 6px 0;
}

.hero-tab-content.active { display: block; }

.hero-notice-list li {
  border-bottom: 1px solid rgba(255,255,255,0.06);
}

.hero-notice-list li:last-child { border-bottom: none; }

.hero-notice-list a {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 24px;
  transition: all var(--transition);
}

.hero-notice-list a:hover {
  background: rgba(255,255,255,0.06);
}

.hero-notice-list a:hover .notice-title {
  color: #7EECD8;
}

.hero-notice-list .badge {
  flex-shrink: 0;
  padding: 3px 10px;
  border-radius: 4px;
  font-size: 11px;
  font-weight: 600;
}

.hero-notice-list .badge-notice {
  background: rgba(126,236,216,0.15);
  color: #7EECD8;
}

.hero-notice-list .badge-news {
  background: rgba(147,197,253,0.15);
  color: #93C5FD;
}

.hero-notice-list .badge-bid {
  background: rgba(134,239,172,0.15);
  color: #86EFAC;
}

.hero-notice-list .badge-closed {
  background: rgba(255,255,255,0.08);
  color: rgba(255,255,255,0.4);
}

.hero-notice-list .notice-title {
  flex: 1;
  font-size: 14px;
  color: rgba(255,255,255,0.8);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  transition: color var(--transition);
}

.hero-notice-list .notice-date {
  flex-shrink: 0;
  font-size: 12px;
  color: rgba(255,255,255,0.35);
  font-family: var(--font-en);
}

.hero-scroll {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: rgba(255,255,255,0.6);
  font-family: var(--font-en);
  font-size: 12px;
  letter-spacing: 2px;
  z-index: 2;
}

.scroll-line {
  width: 1px;
  height: 40px;
  background: rgba(255,255,255,0.3);
  position: relative;
  overflow: hidden;
}

.scroll-line::after {
  content: '';
  position: absolute;
  top: -100%;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--white);
  animation: scrollDown 2s ease-in-out infinite;
}

@keyframes scrollDown {
  0% { top: -100%; }
  50% { top: 100%; }
  100% { top: 100%; }
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== Sections ===== */
.section {
  padding: 120px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 72px;
}

.section-label {
  font-family: var(--font-en);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--primary);
  margin-bottom: 16px;
  display: block;
}

.section-title {
  font-size: clamp(28px, 3.5vw, 42px);
  font-weight: 800;
  color: var(--gray-900);
  line-height: 1.35;
  letter-spacing: -0.5px;
}

.section-desc {
  font-size: 17px;
  color: var(--gray-600);
  margin-top: 16px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

.section-dark {
  background: var(--gray-900);
}

.section-header-light .section-label {
  color: var(--accent-light);
}

.section-header-light .section-title {
  color: var(--white);
}

/* ===== About ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.about-text p {
  font-size: 16px;
  color: var(--gray-700);
  margin-bottom: 20px;
  line-height: 1.85;
}

.about-text p:first-child {
  font-size: 18px;
  font-weight: 600;
  color: var(--gray-900);
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 40px;
  padding-top: 40px;
  border-top: 1px solid var(--gray-200);
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-family: var(--font-en);
  font-size: 36px;
  font-weight: 800;
  color: var(--primary);
  display: inline;
}

.stat-suffix {
  font-family: var(--font-en);
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
}

.stat-label {
  display: block;
  font-size: 14px;
  color: var(--gray-500);
  margin-top: 4px;
}

.about-image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  position: relative;
}

.about-image::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(14,179,157,0.15);
}

.about-image img {
  width: 100%;
  height: 400px;
  object-fit: cover;
  transition: transform 0.6s ease;
}

.about-image:hover img {
  transform: scale(1.03);
}

/* ===== Competency ===== */
.competency-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.comp-card {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
}

.comp-card:hover {
  background: rgba(255,255,255,0.08);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0,0,0,0.3);
}

.comp-card-image {
  height: 220px;
  overflow: hidden;
}

.comp-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease;
}

.comp-card:hover .comp-card-image img {
  transform: scale(1.05);
}

.comp-card-body {
  padding: 32px;
}

.comp-number {
  font-family: var(--font-en);
  font-size: 13px;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 1px;
}

.comp-card-body h3 {
  font-family: var(--font-en);
  font-size: 20px;
  font-weight: 700;
  color: var(--white);
  margin: 8px 0 12px;
}

.comp-card-body p {
  font-size: 14px;
  color: rgba(255,255,255,0.65);
  line-height: 1.7;
}

.comp-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 20px;
}

.comp-tags span {
  padding: 4px 14px;
  background: rgba(14,179,157,0.15);
  color: var(--primary);
  font-size: 13px;
  font-weight: 500;
  border-radius: 100px;
  border: 1px solid rgba(14,179,157,0.25);
}

/* ===== Services ===== */
.section-services {
  background: var(--gray-100);
}

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

.service-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: all var(--transition);
  border: 1px solid var(--gray-200);
}

.service-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(14,179,157,0.3);
}

.service-icon {
  width: 56px;
  height: 56px;
  color: var(--primary);
  margin-bottom: 24px;
}

.service-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 12px;
}

.service-card > p {
  font-size: 14px;
  color: var(--gray-600);
  margin-bottom: 20px;
  line-height: 1.6;
}

.service-card ul {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.service-card li {
  font-size: 13px;
  color: var(--gray-600);
  padding-left: 16px;
  position: relative;
}

.service-card li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--primary);
}

/* ===== Solutions ===== */
.solutions-list {
  display: flex;
  flex-direction: column;
  gap: 64px;
}

.solution-item {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.solution-reverse {
  direction: rtl;
}

.solution-reverse > * {
  direction: ltr;
}

.solution-image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.solution-image img {
  width: 100%;
  height: 340px;
  object-fit: cover;
  transition: transform 0.6s ease;
}

.solution-item:hover .solution-image img {
  transform: scale(1.03);
}

.solution-number {
  font-family: var(--font-en);
  font-size: 48px;
  font-weight: 800;
  color: var(--primary-light);
  line-height: 1;
}

.solution-content h3 {
  font-family: var(--font-en);
  font-size: 24px;
  font-weight: 700;
  color: var(--gray-900);
  margin: 8px 0 16px;
}

.solution-content p {
  font-size: 16px;
  color: var(--gray-700);
  line-height: 1.7;
}

.solution-sub {
  color: var(--gray-500) !important;
  font-size: 15px !important;
  margin-top: 12px;
}

/* ===== Why LogicHub ===== */
.section-why {
  background: linear-gradient(135deg, var(--primary-dark) 0%, #0a3d3a 100%);
}

.why-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 28px;
}

.why-card {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: all var(--transition);
}

.why-card:hover {
  background: rgba(255,255,255,0.1);
  transform: translateY(-4px);
}

.why-icon {
  width: 56px;
  height: 56px;
  color: var(--primary);
  margin-bottom: 24px;
}

.why-card h3 {
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 12px;
  line-height: 1.5;
}

.why-card p {
  font-size: 14px;
  color: rgba(255,255,255,0.6);
  line-height: 1.7;
}

/* ===== Reference ===== */
.reference-main {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
  margin-bottom: 56px;
}

.reference-image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.reference-image img {
  width: 100%;
  height: 360px;
  object-fit: cover;
}

.reference-content h3 {
  font-size: 24px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 16px;
}

.reference-content > p {
  font-size: 15px;
  color: var(--gray-600);
  line-height: 1.7;
  margin-bottom: 32px;
}

.reference-highlights {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.ref-highlight {
  background: var(--primary-light);
  border-radius: var(--radius);
  padding: 20px 16px;
  text-align: center;
}

.ref-highlight strong {
  display: block;
  font-size: 13px;
  color: var(--gray-600);
  margin-bottom: 4px;
}

.ref-highlight span {
  font-family: var(--font-en);
  font-size: 20px;
  font-weight: 800;
  color: var(--primary-dark);
}

.reference-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.ref-card {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--gray-200);
  transition: all var(--transition);
}

.ref-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.ref-card img {
  width: 100%;
  height: 180px;
  object-fit: cover;
}

.ref-card-body {
  padding: 20px;
}

.ref-card-body h4 {
  font-size: 15px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 8px;
  line-height: 1.4;
}

.ref-card-body p {
  font-size: 13px;
  color: var(--gray-500);
  line-height: 1.6;
}

/* ===== Notice ===== */
.section-notice-full {
  background: var(--gray-100);
  padding: 100px 0;
}

.notice-full-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

.notice-block {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 32px;
  border: 1px solid var(--gray-200);
}

.notice-block-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--primary);
}

.notice-block-header h3 {
  font-size: 20px;
  font-weight: 700;
  color: var(--gray-900);
}

.more-link {
  font-size: 14px;
  color: var(--gray-500);
  font-weight: 500;
}

.more-link:hover { color: var(--primary); }

.notice-list li {
  border-bottom: 1px solid var(--gray-100);
}

.notice-list li:last-child {
  border-bottom: none;
}

.notice-list a {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 0;
  transition: all var(--transition);
}

.notice-list a:hover {
  padding-left: 4px;
}

.notice-list a:hover .notice-title {
  color: var(--primary);
}

.badge {
  flex-shrink: 0;
  padding: 3px 10px;
  border-radius: 4px;
  font-size: 12px;
  font-weight: 600;
}

.badge-bid {
  background: #e8f5e9;
  color: #2e7d32;
}

.badge-closed {
  background: var(--gray-100);
  color: var(--gray-500);
}

.badge-notice {
  background: var(--primary-light);
  color: var(--primary-dark);
}

.badge-news {
  background: #e3f2fd;
  color: #1565c0;
}

.notice-title {
  flex: 1;
  font-size: 14px;
  color: var(--gray-700);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  transition: color var(--transition);
}

.notice-date {
  flex-shrink: 0;
  font-size: 13px;
  color: var(--gray-400);
  font-family: var(--font-en);
}

/* ===== Footer ===== */
.footer {
  background: var(--gray-900);
  padding: 64px 0 32px;
  color: rgba(255,255,255,0.6);
}

.footer-top {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 64px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-logo img {
  height: 56px;
  margin-bottom: 16px;
}

.footer-tagline {
  font-size: 14px;
  color: rgba(255,255,255,0.4);
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.footer-col h4 {
  font-family: var(--font-en);
  font-size: 14px;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 16px;
  letter-spacing: 1px;
}

.footer-col a,
.footer-col p {
  display: block;
  font-size: 14px;
  color: rgba(255,255,255,0.45);
  margin-bottom: 10px;
  transition: color var(--transition);
}

.footer-col a:hover {
  color: var(--primary);
}

.footer-bottom {
  padding-top: 32px;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
}

.footer-info p {
  font-size: 13px;
  color: rgba(255,255,255,0.3);
  line-height: 1.8;
}

.copyright {
  font-size: 13px;
  color: rgba(255,255,255,0.25);
  font-family: var(--font-en);
}

/* ===== Back to Top ===== */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--primary);
  color: var(--white);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all var(--transition);
  box-shadow: 0 4px 16px rgba(14,179,157,0.35);
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--primary-deeper);
  transform: translateY(-2px);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
}

/* ===== Scroll Animations ===== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .services-grid { grid-template-columns: repeat(2, 1fr); }
  .why-grid { grid-template-columns: repeat(2, 1fr); }
  .competency-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .hide-mobile { display: none; }

  .section { padding: 80px 0; }

  .nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(29,92,88,0.97);
    backdrop-filter: blur(16px);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 24px;
    z-index: 999;
  }

  .nav.open { display: flex; }

  .nav-link {
    font-size: 20px;
    color: rgba(255,255,255,0.9) !important;
  }

  .hamburger {
    display: flex;
    z-index: 1001;
  }

  .hamburger.open span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }
  .hamburger.open span:nth-child(2) { opacity: 0; }
  .hamburger.open span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .hamburger.open span {
    background: var(--white) !important;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .about-image { order: -1; }

  .about-stats {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
  }

  .stat-number { font-size: 28px; }

  .competency-grid { grid-template-columns: 1fr; }

  .services-grid { grid-template-columns: 1fr; }

  .solution-item {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .solution-reverse { direction: ltr; }

  .why-grid { grid-template-columns: 1fr; }

  .reference-main {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .reference-cards { grid-template-columns: 1fr; }

  .reference-highlights {
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
  }

  .notice-full-grid { grid-template-columns: 1fr; }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .footer-links { grid-template-columns: repeat(2, 1fr); }

  .footer-bottom { flex-direction: column; gap: 16px; align-items: flex-start; }

  .hero-content {
    padding-top: 100px;
    grid-template-columns: 1fr;
    gap: 0;
  }

  .hero-notice {
    grid-column: 1;
    grid-row: auto;
    margin-top: 32px;
  }

  .hero-scroll { display: none; }

  .section-header { margin-bottom: 48px; }
}

@media (max-width: 480px) {
  .hero-buttons { flex-direction: column; }
  .hero-buttons .btn { width: 100%; }
  .reference-highlights { grid-template-columns: 1fr; }
  .about-stats { grid-template-columns: 1fr; }
  .footer-links { grid-template-columns: 1fr; }
}