/* ============================================================
   Wuhan Dongning Eye Technology Co., Ltd - Main Stylesheet
   Precision Optoelectronic Industrial Technology Style
   Color: Tech Ice Blue #29B6F6 | Titanium Deep Gray #263238
   ============================================================ */

/* ----- Tailwind CDN Loaded via HTML ----- */

/* ----- CSS Custom Properties ----- */
:root {
  --ice-blue: #29B6F6;
  --ice-blue-dark: #0288D1;
  --ice-blue-glow: rgba(41, 182, 246, 0.18);
  --ice-blue-soft: rgba(41, 182, 246, 0.08);
  --titanium: #263238;
  --titanium-light: #37474F;
  --titanium-lighter: #455A64;
  --dark-bg: #0D171A;
  --dark-bg-soft: #111D22;
  --dark-surface: #162329;
  --dark-surface-hover: #1B2D35;
  --text-primary: #ECEFF1;
  --text-secondary: #90A4AE;
  --text-muted: #607D8B;
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-medium: rgba(255, 255, 255, 0.10);
  --glass-bg: rgba(22, 35, 41, 0.85);
  --glass-border: rgba(41, 182, 246, 0.12);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --shadow-card: 0 2px 16px rgba(0, 0, 0, 0.35), 0 0 1px rgba(41, 182, 246, 0.06);
  --shadow-card-hover: 0 8px 32px rgba(0, 0, 0, 0.45), 0 0 2px rgba(41, 182, 246, 0.15);
  --shadow-glow: 0 0 40px rgba(41, 182, 246, 0.08);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
  background-color: var(--dark-bg);
  color: var(--text-primary);
  line-height: 1.65;
  overflow-x: hidden;
  min-height: 100vh;
}

/* Subtle background grid pattern */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    linear-gradient(rgba(41, 182, 246, 0.015) 1px, transparent 1px),
    linear-gradient(90deg, rgba(41, 182, 246, 0.015) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
  z-index: 0;
}

a { color: var(--ice-blue); text-decoration: none; transition: color var(--transition-fast); }
a:hover { color: #4FC3F7; }

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

/* ----- Typography ----- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

.gradient-text {
  background: linear-gradient(135deg, #E0F7FA 0%, var(--ice-blue) 50%, #81D4FA 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.gradient-text-ice {
  background: linear-gradient(135deg, var(--ice-blue) 0%, #4FC3F7 60%, #B3E5FC 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ----- Navigation ----- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(13, 23, 26, 0.82);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--border-subtle);
  transition: all var(--transition-smooth);
}

.navbar.scrolled {
  background: rgba(13, 23, 26, 0.94);
  box-shadow: 0 1px 20px rgba(0, 0, 0, 0.5);
}

.nav-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.nav-logo .logo-icon {
  width: 34px;
  height: 34px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--ice-blue) 0%, #0277BD 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: #fff;
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
}

.nav-links a {
  display: block;
  padding: 8px 18px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  letter-spacing: 0.01em;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--ice-blue);
  background: var(--ice-blue-soft);
}

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

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all var(--transition-fast);
}

/* ----- Hero Section ----- */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 80px;
  overflow: hidden;
  background: radial-gradient(ellipse 80% 60% at 50% 35%, rgba(41, 182, 246, 0.06) 0%, transparent 70%),
              radial-gradient(ellipse 60% 50% at 80% 20%, rgba(2, 119, 189, 0.05) 0%, transparent 60%);
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: url('../images/hero-bg.jpg');
  background-size: cover;
  background-position: center;
  opacity: 0.12;
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 900px;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border: 1px solid var(--glass-border);
  border-radius: 100px;
  background: rgba(41, 182, 246, 0.06);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--ice-blue);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 28px;
  backdrop-filter: blur(8px);
}

.hero-badge .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--ice-blue);
  box-shadow: 0 0 8px var(--ice-blue);
  animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.6); }
}

.hero h1 {
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  line-height: 1.15;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 36px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ----- Buttons ----- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all var(--transition-smooth);
  letter-spacing: 0.02em;
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--ice-blue) 0%, #0288D1 100%);
  color: #fff;
  box-shadow: 0 4px 20px rgba(41, 182, 246, 0.25);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(41, 182, 246, 0.4);
  color: #fff;
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  backdrop-filter: blur(8px);
}

.btn-outline:hover {
  border-color: var(--ice-blue);
  background: rgba(41, 182, 246, 0.06);
  color: var(--ice-blue);
}

/* ----- Section Common ----- */
.section {
  position: relative;
  padding: 100px 24px;
  z-index: 1;
}

.section-container {
  max-width: 1280px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-label {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--ice-blue);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 700;
  margin-bottom: 14px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 620px;
  margin: 0 auto;
  line-height: 1.7;
}

/* ----- Feature Cards Grid ----- */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.card {
  position: relative;
  background: var(--dark-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  transition: all var(--transition-smooth);
  overflow: hidden;
  z-index: 1;
}

.card::before {
  content: '';
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  opacity: 0.06;
  z-index: 0;
  transition: opacity var(--transition-smooth);
}

.card:hover::before {
  opacity: 0.10;
}

.card:hover {
  border-color: var(--glass-border);
  background: var(--dark-surface-hover);
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
}

.card > * {
  position: relative;
  z-index: 1;
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, rgba(41, 182, 246, 0.15) 0%, rgba(2, 119, 189, 0.08) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  color: var(--ice-blue);
  margin-bottom: 20px;
  border: 1px solid var(--glass-border);
}

.card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 10px;
  color: var(--text-primary);
}

.card p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* Card background images */
.card-bg-vision { background-image: url('../images/card-vision.jpg'); }
.card-bg-cv { background-image: url('../images/card-cv.jpg'); }
.card-bg-comfort { background-image: url('../images/card-comfort.jpg'); }
.card-bg-verify { background-image: url('../images/card-verify.jpg'); }

/* ----- Advantage Strip ----- */
.advantage-strip {
  background: linear-gradient(180deg, rgba(22, 35, 41, 0.6) 0%, var(--dark-bg-soft) 100%);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.advantage-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 40px;
  text-align: center;
}

.advantage-item .adv-number {
  font-size: 2.4rem;
  font-weight: 800;
  color: var(--ice-blue);
  letter-spacing: -0.02em;
  line-height: 1;
  margin-bottom: 8px;
}

.advantage-item .adv-label {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* ----- Technology Detail Section ----- */
.tech-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin-bottom: 80px;
}

.tech-block:last-child { margin-bottom: 0; }

.tech-block.reverse { direction: rtl; }
.tech-block.reverse > * { direction: ltr; }

.tech-visual {
  position: relative;
  border-radius: var(--radius-xl);
  overflow: hidden;
  aspect-ratio: 4/3;
  background-size: cover;
  background-position: center;
  border: 1px solid var(--border-subtle);
}

.tech-visual::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(38, 50, 56, 0.5) 0%, rgba(13, 23, 26, 0.7) 100%);
  z-index: 1;
}

.tech-visual .tech-visual-icon {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 2;
  font-size: 3rem;
  color: var(--ice-blue);
  opacity: 0.8;
}

.tech-visual-bg-1 { background-image: url('../images/p1.jpg'); }
.tech-visual-bg-2 { background-image: url('../images/p2.jpg'); }
.tech-visual-bg-3 { background-image: url('../images/p3.jpg'); }
.tech-visual-bg-4 { background-image: url('../images/p4.jpg'); }

.tech-info h2 {
  font-size: 1.7rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.tech-info .tech-tag {
  display: inline-block;
  padding: 4px 12px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--ice-blue);
  border: 1px solid var(--glass-border);
  border-radius: 100px;
  background: var(--ice-blue-soft);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.tech-info p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.75;
  margin-bottom: 20px;
}

.tech-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.tech-features li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.tech-features li::before {
  content: '◆';
  color: var(--ice-blue);
  font-size: 0.55rem;
  margin-top: 5px;
  flex-shrink: 0;
}

/* ----- Contact Page ----- */
.contact-hero {
  min-height: 50vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 140px 24px 80px;
  background: radial-gradient(ellipse 70% 50% at 50% 40%, rgba(41, 182, 246, 0.05) 0%, transparent 70%);
  position: relative;
}

.contact-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: url('../images/contact-hero.jpg');
  background-size: cover;
  background-position: center;
  opacity: 0.1;
}

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

.contact-card {
  position: relative;
  background: var(--dark-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
  transition: all var(--transition-smooth);
  overflow: hidden;
}

.contact-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  opacity: 0.05;
  z-index: 0;
}

.contact-card > * { position: relative; z-index: 1; }

.contact-card-bg-1::before { background-image: url('../images/p5.jpg'); }
.contact-card-bg-2::before { background-image: url('../images/p6.jpg'); }

.contact-card:hover {
  border-color: var(--glass-border);
  box-shadow: var(--shadow-card-hover);
}

.contact-card-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, rgba(41, 182, 246, 0.15) 0%, rgba(2, 119, 189, 0.08) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: var(--ice-blue);
  margin-bottom: 18px;
  border: 1px solid var(--glass-border);
}

.contact-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.contact-card p, .contact-card address {
  font-size: 0.92rem;
  color: var(--text-secondary);
  font-style: normal;
  line-height: 1.7;
}

.contact-card a {
  color: var(--ice-blue);
  font-weight: 500;
}

.contact-map-area {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  background: var(--dark-surface);
  min-height: 260px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.contact-map-area::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: url('../images/map-bg.jpg');
  background-size: cover;
  background-position: center;
  opacity: 0.15;
}

/* ----- Footer ----- */
.footer {
  background: var(--dark-bg-soft);
  border-top: 1px solid var(--border-subtle);
  padding: 48px 24px 28px;
  position: relative;
  z-index: 1;
}

.footer-container {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}

.footer-info p {
  font-size: 0.85rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.footer-info .company-name {
  color: var(--text-secondary);
  font-weight: 600;
  margin-bottom: 4px;
}

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

.footer-links a {
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.footer-links a:hover { color: var(--ice-blue); }

.footer-bottom {
  max-width: 1280px;
  margin: 24px auto 0;
  padding-top: 20px;
  border-top: 1px solid var(--border-subtle);
  text-align: center;
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* ----- Page Banner (Technology / Contact pages) ----- */
.page-banner {
  position: relative;
  padding: 140px 24px 60px;
  text-align: center;
  overflow: hidden;
}

.page-banner::before {
  content: '';
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  opacity: 0.1;
  z-index: 0;
}

.page-banner-tech::before { background-image: url('../images/tech-banner.jpg'); }
.page-banner-contact::before { background-image: url('../images/contact-banner.jpg'); }

.page-banner > * { position: relative; z-index: 1; }

.page-banner h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  margin-bottom: 14px;
}

.page-banner p {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.7;
}

/* ----- Animations ----- */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1),
              transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

/* Tech line decoration */
.tech-line {
  position: absolute;
  background: linear-gradient(90deg, transparent, var(--ice-blue-glow), transparent);
  height: 1px;
  width: 100%;
}

.tech-line-h {
  position: absolute;
  background: linear-gradient(180deg, transparent, var(--ice-blue-glow), transparent);
  width: 1px;
  height: 100%;
}

/* Glow orb decoration */
.glow-orb {
  position: absolute;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(41, 182, 246, 0.12) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

/* Scroll line animation */
.scroll-indicator {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: var(--text-muted);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.scroll-line {
  width: 1px;
  height: 40px;
  background: linear-gradient(180deg, var(--ice-blue) 0%, transparent 100%);
  animation: scroll-line 2s ease-in-out infinite;
}

@keyframes scroll-line {
  0%, 100% { transform: scaleY(0.4); opacity: 0.3; }
  50% { transform: scaleY(1); opacity: 0.8; }
}

/* ----- Responsive ----- */
@media (max-width: 1024px) {
  .tech-block {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .tech-block.reverse { direction: ltr; }
  .tech-visual { aspect-ratio: 16/9; }
  .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(13, 23, 26, 0.96);
    backdrop-filter: blur(20px);
    padding: 16px;
    gap: 4px;
    border-bottom: 1px solid var(--border-subtle);
    transform: translateY(-120%);
    transition: transform var(--transition-smooth);
    z-index: 999;
  }
  .nav-links.open { transform: translateY(0); }
  .nav-links a { padding: 12px 16px; }
  .nav-toggle { display: flex; }

  .hero { padding: 100px 20px 60px; }
  .section { padding: 60px 20px; }
  .footer-container { flex-direction: column; text-align: center; }
  .footer-links { justify-content: center; }
  .cards-grid { grid-template-columns: 1fr; }
  .advantage-grid { grid-template-columns: repeat(2, 1fr); gap: 28px; }
}

@media (max-width: 480px) {
  .hero-actions { flex-direction: column; align-items: stretch; }
  .btn { justify-content: center; }
  .advantage-grid { grid-template-columns: 1fr; }
  .page-banner { padding: 120px 20px 40px; }
}