/* ============================================
   5G OMAN - Main Stylesheet
   Theme: Futuristic Wave Design
   Colors: Dark Blue BG, Cyan Highlights, White Text
   ============================================ */

/* ---- CSS Variables ---- */
:root {
  --bg-primary: #020b18;
  --bg-secondary: #041525;
  --bg-card: #071e33;
  --bg-card-hover: #0a2744;
  --cyan: #00d4ff;
  --cyan-dark: #0099cc;
  --cyan-glow: rgba(0, 212, 255, 0.15);
  --cyan-glow-strong: rgba(0, 212, 255, 0.35);
  --white: #ffffff;
  --white-muted: rgba(255, 255, 255, 0.75);
  --white-dim: rgba(255, 255, 255, 0.45);
  --border: rgba(0, 212, 255, 0.2);
  --border-strong: rgba(0, 212, 255, 0.45);
  --nav-height: 70px;
  --font-main: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Courier New', monospace;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow-card: 0 4px 30px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 30px rgba(0, 212, 255, 0.2);
  --transition: all 0.3s ease;
}

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

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

body {
  font-family: var(--font-main);
  background-color: var(--bg-primary);
  color: var(--white);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

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

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

a:hover {
  color: #fff;
}

ul {
  list-style: none;
}

/* ---- Typography ---- */
h1, h2, h3, h4, h5 {
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); }
h2 { font-size: clamp(1.7rem, 3.5vw, 2.6rem); }
h3 { font-size: clamp(1.2rem, 2.5vw, 1.6rem); }
h4 { font-size: 1.15rem; }

p {
  color: var(--white-muted);
  margin-bottom: 1rem;
}

p:last-child { margin-bottom: 0; }

.text-cyan { color: var(--cyan); }
.text-white { color: var(--white); }
.text-muted { color: var(--white-dim); }
.text-center { text-align: center; }

/* ---- Layout ---- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 90px 0;
}

.section-sm {
  padding: 60px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-header h2 {
  margin-bottom: 16px;
}

.section-header p {
  max-width: 620px;
  margin: 0 auto;
  font-size: 1.1rem;
}

.section-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--cyan);
  background: var(--cyan-glow);
  border: 1px solid var(--border);
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 18px;
}

/* ---- Navigation ---- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(2, 11, 24, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  transition: var(--transition);
}

.navbar.scrolled {
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-height);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--white);
  letter-spacing: -0.01em;
}

.nav-logo .logo-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, var(--cyan), var(--cyan-dark));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  font-weight: 900;
  color: var(--bg-primary);
  box-shadow: 0 0 20px rgba(0, 212, 255, 0.4);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-link {
  color: var(--white-muted);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: 8px;
  transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--cyan);
  background: var(--cyan-glow);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 8px;
  border: none;
  background: none;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--white);
  border-radius: 2px;
  transition: var(--transition);
}

/* ---- Hero Section ---- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding-top: var(--nav-height);
}

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

.hero-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-gradient {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 40%, rgba(0, 212, 255, 0.08) 0%, transparent 70%),
              linear-gradient(180deg, transparent 60%, var(--bg-primary) 100%);
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 212, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 212, 255, 0.04) 1px, transparent 1px);
  background-size: 60px 60px;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 780px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(0, 212, 255, 0.1);
  border: 1px solid var(--border-strong);
  border-radius: 100px;
  padding: 8px 18px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan);
  margin-bottom: 28px;
}

.hero-badge .dot {
  width: 7px;
  height: 7px;
  background: var(--cyan);
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}

.hero h1 {
  margin-bottom: 24px;
  color: var(--white);
}

.hero h1 span {
  color: var(--cyan);
  text-shadow: 0 0 40px rgba(0, 212, 255, 0.5);
}

.hero-desc {
  font-size: 1.15rem;
  color: var(--white-muted);
  margin-bottom: 40px;
  max-width: 600px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-stats {
  display: flex;
  gap: 48px;
  margin-top: 70px;
  padding-top: 40px;
  border-top: 1px solid var(--border);
}

.stat-item {}
.stat-value {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--cyan);
  line-height: 1;
  margin-bottom: 6px;
}
.stat-label {
  font-size: 0.85rem;
  color: var(--white-dim);
  font-weight: 500;
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--cyan), var(--cyan-dark));
  color: var(--bg-primary);
  box-shadow: 0 0 25px rgba(0, 212, 255, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 40px rgba(0, 212, 255, 0.55);
  color: var(--bg-primary);
}

.btn-outline {
  background: transparent;
  color: var(--cyan);
  border: 1.5px solid var(--border-strong);
}

.btn-outline:hover {
  background: var(--cyan-glow);
  border-color: var(--cyan);
  color: var(--cyan);
  transform: translateY(-2px);
}

/* ---- Cards ---- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
  opacity: 0;
  transition: var(--transition);
}

.card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
  transform: translateY(-4px);
  box-shadow: var(--shadow-card), var(--shadow-glow);
}

.card:hover::before {
  opacity: 1;
}

.card-icon {
  width: 56px;
  height: 56px;
  background: var(--cyan-glow);
  border: 1px solid var(--border);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
  transition: var(--transition);
}

.card:hover .card-icon {
  background: rgba(0, 212, 255, 0.25);
  box-shadow: 0 0 20px rgba(0, 212, 255, 0.3);
}

.card h3 {
  margin-bottom: 12px;
  color: var(--white);
}

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

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

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

.grid-auto {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
}

/* ---- Info Boxes ---- */
.info-box {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 3px solid var(--cyan);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-bottom: 24px;
}

.info-box.warning {
  border-left-color: #f59e0b;
  background: rgba(245, 158, 11, 0.05);
}

/* ---- Page Hero (inner pages) ---- */
.page-hero {
  padding: 140px 0 80px;
  position: relative;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background:
    radial-gradient(ellipse at 30% 50%, rgba(0, 212, 255, 0.06) 0%, transparent 60%),
    linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.page-hero::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 212, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 212, 255, 0.03) 1px, transparent 1px);
  background-size: 50px 50px;
}

.page-hero .container {
  position: relative;
  z-index: 1;
}

.page-hero h1 {
  margin-bottom: 16px;
}

.page-hero p {
  font-size: 1.1rem;
  max-width: 600px;
}

/* ---- Timeline / Steps ---- */
.steps {
  position: relative;
  padding-left: 40px;
}

.steps::before {
  content: '';
  position: absolute;
  left: 15px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), transparent);
}

.step {
  position: relative;
  margin-bottom: 48px;
}

.step:last-child {
  margin-bottom: 0;
}

.step-num {
  position: absolute;
  left: -40px;
  top: 0;
  width: 30px;
  height: 30px;
  background: var(--bg-primary);
  border: 2px solid var(--cyan);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--cyan);
  box-shadow: 0 0 15px rgba(0, 212, 255, 0.3);
}

.step h3 {
  margin-bottom: 10px;
  color: var(--white);
}

/* ---- FAQ Accordion ---- */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  background: var(--bg-card);
  overflow: hidden;
  transition: var(--transition);
}

.faq-item.open {
  border-color: var(--border-strong);
  box-shadow: 0 0 20px rgba(0, 212, 255, 0.1);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 28px;
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  color: var(--white);
  user-select: none;
  gap: 16px;
}

.faq-question:hover {
  color: var(--cyan);
}

.faq-icon {
  width: 28px;
  height: 28px;
  min-width: 28px;
  background: var(--cyan-glow);
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  color: var(--cyan);
  transition: var(--transition);
}

.faq-item.open .faq-icon {
  background: rgba(0, 212, 255, 0.25);
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.3s ease;
  padding: 0 28px;
}

.faq-item.open .faq-answer {
  max-height: 400px;
  padding-bottom: 22px;
}

/* ---- Divider ---- */
.divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-strong), transparent);
  margin: 40px 0;
}

/* ---- Tags / Pills ---- */
.tag {
  display: inline-block;
  background: var(--cyan-glow);
  border: 1px solid var(--border);
  color: var(--cyan);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 100px;
  letter-spacing: 0.05em;
}

/* ---- Feature List ---- */
.feature-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.feature-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.feature-check {
  width: 22px;
  height: 22px;
  min-width: 22px;
  background: var(--cyan-glow);
  border: 1px solid var(--border);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  color: var(--cyan);
  margin-top: 2px;
}

/* ---- Data Table ---- */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

.data-table th {
  background: rgba(0, 212, 255, 0.1);
  color: var(--cyan);
  font-weight: 600;
  text-align: left;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border-strong);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.data-table td {
  padding: 16px 20px;
  color: var(--white-muted);
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}

.data-table tr:last-child td {
  border-bottom: none;
}

.data-table tr:hover td {
  background: var(--cyan-glow);
  color: var(--white);
}

.table-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  overflow-x: auto;
}

/* ---- Disclaimer Banner ---- */
.disclaimer-banner {
  background: rgba(245, 158, 11, 0.07);
  border: 1px solid rgba(245, 158, 11, 0.25);
  border-radius: var(--radius);
  padding: 16px 24px;
  display: flex;
  align-items: flex-start;
  gap: 14px;
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 40px;
}

.disclaimer-banner .disclaimer-icon {
  font-size: 1.1rem;
  min-width: 20px;
  color: #f59e0b;
  margin-top: 2px;
}

/* ---- Contact ---- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.3fr;
  gap: 60px;
  align-items: start;
}

.contact-info-item {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  padding: 24px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 16px;
  transition: var(--transition);
}

.contact-info-item:hover {
  border-color: var(--border-strong);
}

.contact-info-icon {
  width: 44px;
  height: 44px;
  min-width: 44px;
  background: var(--cyan-glow);
  border: 1px solid var(--border);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}

.contact-info-text strong {
  display: block;
  color: var(--white);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 4px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.contact-info-text span {
  color: var(--white-muted);
  font-size: 0.95rem;
}

/* ---- Contact Form ---- */
.form-group {
  margin-bottom: 20px;
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--white-muted);
  margin-bottom: 8px;
  letter-spacing: 0.03em;
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 13px 18px;
  color: var(--white);
  font-family: var(--font-main);
  font-size: 0.95rem;
  outline: none;
  transition: var(--transition);
  -webkit-appearance: none;
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  border-color: var(--cyan);
  box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.1);
}

.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--white-dim);
}

.form-textarea {
  resize: vertical;
  min-height: 130px;
}

/* ---- Footer ---- */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 70px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr 1fr;
  gap: 50px;
  padding-bottom: 60px;
  border-bottom: 1px solid var(--border);
}

.footer-brand p {
  font-size: 0.9rem;
  color: var(--white-dim);
  margin-top: 16px;
  max-width: 260px;
  line-height: 1.6;
}

.footer-col h4 {
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--white);
  margin-bottom: 20px;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  color: var(--white-dim);
  font-size: 0.9rem;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--cyan);
  padding-left: 4px;
}

.footer-bottom {
  padding: 24px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-bottom p {
  font-size: 0.82rem;
  color: var(--white-dim);
  margin: 0;
}

.footer-bottom-links {
  display: flex;
  gap: 24px;
}

.footer-bottom-links a {
  font-size: 0.82rem;
  color: var(--white-dim);
}

.footer-bottom-links a:hover {
  color: var(--cyan);
}

/* ---- Breadcrumb ---- */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.82rem;
  color: var(--white-dim);
  margin-bottom: 20px;
}

.breadcrumb a {
  color: var(--white-dim);
}

.breadcrumb a:hover {
  color: var(--cyan);
}

.breadcrumb span {
  color: var(--white-dim);
}

.breadcrumb .current {
  color: var(--cyan);
}

/* ---- Wave Decoration ---- */
.wave-section {
  position: relative;
}

.wave-top,
.wave-bottom {
  position: absolute;
  left: 0;
  right: 0;
  height: 80px;
  overflow: hidden;
  pointer-events: none;
}

.wave-top { top: -1px; }
.wave-bottom { bottom: -1px; }

/* ---- Glow Orbs ---- */
.glow-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  pointer-events: none;
  opacity: 0.18;
}

.glow-orb-1 {
  width: 500px;
  height: 500px;
  background: var(--cyan);
  top: -200px;
  right: -200px;
}

.glow-orb-2 {
  width: 400px;
  height: 400px;
  background: #0044ff;
  bottom: -150px;
  left: -150px;
}

/* ---- Highlight Box ---- */
.highlight-box {
  background: linear-gradient(135deg, rgba(0, 212, 255, 0.08), rgba(0, 68, 255, 0.06));
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 48px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.highlight-box::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 200px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
}

/* ---- Animations ---- */
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.8); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

@keyframes glow-pulse {
  0%, 100% { box-shadow: 0 0 20px rgba(0, 212, 255, 0.2); }
  50% { box-shadow: 0 0 40px rgba(0, 212, 255, 0.5); }
}

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

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes wave-move {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

.animate-fade-up {
  animation: fadeInUp 0.7s ease forwards;
}

.animate-delay-1 { animation-delay: 0.1s; }
.animate-delay-2 { animation-delay: 0.2s; }
.animate-delay-3 { animation-delay: 0.3s; }
.animate-delay-4 { animation-delay: 0.4s; }

/* ---- Scroll Reveal ---- */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---- Spec Badge ---- */
.spec-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
}

.spec-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
  transition: var(--transition);
}

.spec-item:hover {
  border-color: var(--border-strong);
  background: var(--bg-card-hover);
}

.spec-value {
  font-size: 2rem;
  font-weight: 800;
  color: var(--cyan);
  line-height: 1;
  margin-bottom: 8px;
}

.spec-unit {
  font-size: 0.9rem;
  color: var(--white-dim);
}

.spec-label {
  font-size: 0.82rem;
  color: var(--white-muted);
  font-weight: 500;
  margin-top: 8px;
}

/* ---- Back to top ---- */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 44px;
  height: 44px;
  background: var(--cyan);
  color: var(--bg-primary);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transition: var(--transition);
  z-index: 999;
  box-shadow: 0 0 20px rgba(0, 212, 255, 0.4);
  border: none;
}

.back-to-top.visible {
  opacity: 1;
  pointer-events: all;
}

.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: 0 0 30px rgba(0, 212, 255, 0.6);
}

/* ---- Separator ---- */
.alt-bg {
  background: var(--bg-secondary);
}

/* ============================================
   RESPONSIVE
   ============================================ */

@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
  }

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

@media (max-width: 768px) {
  .nav-menu {
    display: none;
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: rgba(2, 11, 24, 0.98);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 20px 24px;
    gap: 4px;
    backdrop-filter: blur(20px);
  }

  .nav-menu.open {
    display: flex;
  }

  .nav-link {
    width: 100%;
    padding: 12px 16px;
  }

  .nav-toggle {
    display: flex;
  }

  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }

  .hero-stats {
    gap: 28px;
    flex-wrap: wrap;
  }

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

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

  .highlight-box {
    padding: 32px 24px;
  }

  .section {
    padding: 70px 0;
  }
}

@media (max-width: 480px) {
  .hero-actions {
    flex-direction: column;
  }

  .btn {
    justify-content: center;
  }

  .hero-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
  }
}
</style>