/* ============================================
   无锡泉控阀门流体控制有限公司 - 企业官网
   Style V3: Blue Tech - 蓝色科技风
   ============================================ */

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

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-deep: #1e3a8a;
  --primary-glow: #3b82f6;
  --accent: #06b6d4;
  --accent-glow: #22d3ee;
  --bg-tech: #0b1121;
  --bg-card: rgba(15, 23, 42, 0.8);
  --bg-page: #f0f4ff;
  --bg-white: #ffffff;
  --text-dark: #0f172a;
  --text-body: #475569;
  --text-muted: #94a3b8;
  --border: #e2e8f0;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.06);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.08);
  --shadow-glow: 0 0 40px rgba(37, 99, 235, 0.15);
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --max-width: 1200px;
  --nav-height: 74px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
  color: var(--text-body);
  background: var(--bg-page);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
ul, ol { list-style: none; }
img { max-width: 100%; display: block; }

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 28px; }

/* --- Typography --- */
h1, h2, h3, h4 { color: var(--text-dark); font-weight: 700; line-height: 1.3; }
h1 { font-size: 3rem; letter-spacing: -0.5px; }
h2 { font-size: 2.2rem; }
h3 { font-size: 1.2rem; }

.section-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 1.5px;
  color: var(--primary);
  background: rgba(37, 99, 235, 0.08);
  padding: 5px 14px;
  border-radius: 4px;
  margin-bottom: 14px;
}

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

.section-title h2 { margin-bottom: 14px; }

.section-title p {
  color: var(--text-muted);
  font-size: 1rem;
  max-width: 520px;
  margin: 0 auto;
}

.section-title.dark h2 { color: #fff; }
.section-title.dark p { color: rgba(255,255,255,0.55); }
.section-tag.dark { color: var(--accent-glow); background: rgba(34, 211, 238, 0.12); }

/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-height);
  background: rgba(11, 17, 33, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255,255,255,0.06);
  z-index: 1000;
  transition: all var(--transition);
}

.nav.scrolled {
  box-shadow: 0 2px 24px rgba(0,0,0,0.3);
  background: rgba(11, 17, 33, 0.96);
}

.nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.1rem;
  font-weight: 700;
  color: #fff;
}

.nav-brand .logo-img {
  height: 36px;
  width: auto;
  object-fit: contain;
  flex-shrink: 0;
  display: block;
}

.nav-links { display: flex; align-items: center; gap: 4px; }

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: rgba(255,255,255,0.55);
  padding: 8px 16px;
  border-radius: 6px;
  transition: all var(--transition);
}

.nav-links a:hover {
  color: #fff;
  background: rgba(255,255,255,0.06);
}

.nav-links a.active {
  color: #fff;
  background: rgba(37, 99, 235, 0.2);
  font-weight: 600;
}

.nav-actions { display: flex; align-items: center; gap: 10px; }

.lang-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px; height: 34px;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 6px;
  color: rgba(255,255,255,0.7);
  font-size: 0.75rem;
  font-weight: 700;
  cursor: pointer;
  letter-spacing: 0.5px;
  transition: all var(--transition);
  font-family: inherit;
}
.lang-toggle:hover {
  background: rgba(37, 99, 235, 0.2);
  border-color: rgba(37, 99, 235, 0.3);
  color: #fff;
}

.nav-toggle { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; background: none; border: none; }
.nav-toggle span { width: 24px; height: 2px; background: #fff; border-radius: 2px; transition: var(--transition); }

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

/* Tech grid background */
.hero-grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(37, 99, 235, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.04) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse at 50% 40%, black 30%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at 50% 40%, black 30%, transparent 70%);
  pointer-events: none;
}

/* Glow orbs */
.hero-glow-1 {
  position: absolute;
  top: -20%; right: -10%;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.15), transparent 70%);
  pointer-events: none;
}
.hero-glow-2 {
  position: absolute;
  bottom: -10%; left: -5%;
  width: 500px; height: 500px;
  background: radial-gradient(circle, rgba(6, 182, 212, 0.08), transparent 70%);
  pointer-events: none;
}

.hero .container {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(37, 99, 235, 0.2);
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
  color: #93c5fd;
  margin-bottom: 28px;
}

.hero-badge::before {
  content: '';
  width: 7px; height: 7px;
  background: var(--accent-glow);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--accent-glow);
  animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(1.5); }
}

.hero-content h1 {
  font-size: 3.2rem;
  color: #fff;
  margin-bottom: 20px;
  line-height: 1.2;
}

.hero-content h1 .gradient-text {
  background: linear-gradient(135deg, #60a5fa, #22d3ee);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-content .hero-subtitle {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.55);
  margin-bottom: 40px;
  max-width: 460px;
  line-height: 1.8;
}

.hero-buttons {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 60px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 30px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: 8px;
  cursor: pointer;
  border: none;
  transition: all var(--transition);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.35);
}

.btn-primary:hover {
  box-shadow: 0 6px 28px rgba(37, 99, 235, 0.5);
  transform: translateY(-2px);
}

.btn-outline {
  background: transparent;
  color: #fff;
  border: 1.5px solid rgba(255,255,255,0.2);
}

.btn-outline:hover {
  border-color: rgba(255,255,255,0.5);
  background: rgba(255,255,255,0.05);
}

.btn-white {
  background: var(--bg-white);
  color: var(--primary);
  box-shadow: var(--shadow-md);
}
.btn-white:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.hero-stats {
  display: flex;
  gap: 48px;
}

.hero-stat {
  position: relative;
}

.hero-stat .num {
  font-size: 2.2rem;
  font-weight: 800;
  background: linear-gradient(135deg, #60a5fa, #22d3ee);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  display: block;
  line-height: 1;
}

.hero-stat .label {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.4);
  margin-top: 6px;
}

/* Hero visual - Valve illustration */
.hero-visual {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.valve-illustration {
  width: 100%;
  max-width: 340px;
  height: auto;
  filter: drop-shadow(0 0 30px rgba(37, 99, 235, 0.15));
}

/* --- About Section --- */
.about {
  padding: 120px 0;
  background: var(--bg-white);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
  align-items: center;
}

.about-image {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: linear-gradient(150deg, var(--bg-tech), #1e293b);
  aspect-ratio: 4 / 3;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
}

.about-image .icon-xl {
  font-size: 6rem;
  opacity: 0.15;
  color: var(--primary-glow);
}

.about-image .badge-float {
  position: absolute;
  bottom: 24px; right: 24px;
  background: rgba(255,255,255,0.1);
  backdrop-filter: blur(10px);
  padding: 12px 20px;
  border-radius: 10px;
  font-size: 0.85rem;
  font-weight: 700;
  color: #fff;
  border: 1px solid rgba(255,255,255,0.1);
}

.about-text h2 { margin-bottom: 20px; }

.about-text .lead {
  font-size: 1.08rem;
  color: var(--text-body);
  margin-bottom: 16px;
  line-height: 1.85;
}

.about-text p {
  color: var(--text-muted);
  margin-bottom: 36px;
  line-height: 1.85;
}

.about-features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.about-feature {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 20px;
  background: var(--bg-page);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--primary);
  transition: all var(--transition);
}

.about-feature:nth-child(2) { border-left-color: var(--accent); }
.about-feature:nth-child(3) { border-left-color: var(--primary-glow); }
.about-feature:nth-child(4) { border-left-color: var(--accent); }

.about-feature:hover {
  background: var(--bg-white);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.about-feature .icon {
  width: 44px; height: 44px;
  background: rgba(37, 99, 235, 0.08);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  flex-shrink: 0;
  font-size: 1.25rem;
}

.about-feature h4 { font-weight: 600; margin-bottom: 2px; font-size: 0.95rem; }
.about-feature p { font-size: 0.82rem; color: var(--text-muted); margin: 0; line-height: 1.5; }

/* --- Products Section --- */
.products {
  padding: 120px 0;
  background: var(--bg-page);
}

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

.product-grid::after {
  content: '';
  grid-column: 1 / -1;
}

.product-card {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1.5px solid #d1d5db;
  transition: all var(--transition);
  cursor: pointer;
  position: relative;
}

.product-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  opacity: 0;
  transition: opacity var(--transition);
}

.product-card:hover {
  box-shadow: 0 12px 40px rgba(37, 99, 235, 0.15), 0 0 0 1px rgba(37, 99, 235, 0.3);
  transform: translateY(-6px);
  border-color: rgba(37, 99, 235, 0.4);
}

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

.product-card-image {
  height: 150px;
  background: linear-gradient(135deg, #f0f4ff, #e0e7ff);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  color: var(--primary);
  position: relative;
  overflow: hidden;
}

.product-card-image::after {
  content: '';
  position: absolute;
  top: -20px; right: -20px;
  width: 70px; height: 70px;
  background: var(--primary);
  opacity: 0.04;
  border-radius: 50%;
}

.product-card-body { padding: 22px; }

.product-card-body h3 { font-size: 1rem; margin-bottom: 8px; color: var(--text-dark); }
.product-card-body p { font-size: 0.8rem; color: var(--text-muted); line-height: 1.65; }

.product-tag {
  display: inline-block;
  padding: 4px 12px;
  background: rgba(37, 99, 235, 0.08);
  color: var(--primary);
  font-size: 0.7rem;
  font-weight: 700;
  border-radius: 4px;
  margin-top: 14px;
  letter-spacing: 0.3px;
}

/* Service highlight */
.service-highlight {
  margin-top: 72px;
  background: linear-gradient(135deg, #eff6ff, #f0f9ff);
  border-radius: var(--radius-xl);
  border: 1.5px solid rgba(37, 99, 235, 0.15);
  padding: 56px 60px;
  position: relative;
  overflow: hidden;
}

.service-highlight::before {
  content: '';
  position: absolute;
  top: -30%; right: -10%;
  width: 300px; height: 300px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.06), transparent 70%);
  pointer-events: none;
}

.service-highlight-header {
  text-align: center;
  margin-bottom: 40px;
  position: relative;
}

.service-highlight-header h3 {
  color: var(--text-dark);
  font-size: 1.5rem;
  margin-bottom: 12px;
}

.service-highlight-header p {
  color: var(--text-body);
  line-height: 1.75;
  margin-bottom: 24px;
  max-width: 620px;
  margin-left: auto;
  margin-right: auto;
}

.service-highlight-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  position: relative;
}

.service-highlight-item {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  padding: 28px 22px;
  text-align: center;
  border: 1.5px solid var(--border);
  transition: all var(--transition);
}

.service-highlight-item:hover {
  box-shadow: var(--shadow-md);
  border-color: rgba(37, 99, 235, 0.2);
  transform: translateY(-3px);
}

.service-highlight-item .icon {
  width: 52px; height: 52px;
  background: rgba(37, 99, 235, 0.08);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  font-size: 1.4rem;
  margin: 0 auto 14px;
}

.service-highlight-item h4 {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 6px;
}

.service-highlight-item p {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.service-highlight .btn-white {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.25);
}
.service-highlight .btn-white:hover {
  box-shadow: 0 6px 28px rgba(37, 99, 235, 0.4);
  transform: translateY(-2px);
}

/* --- Contact Section --- */
.contact {
  padding: 120px 0;
  background: var(--bg-white);
}

.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
}

.contact-info h2 { margin-bottom: 12px; }

.contact-info > p { color: var(--text-muted); margin-bottom: 36px; }

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 18px 20px;
  background: var(--bg-page);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  border: 1px solid var(--border);
  transition: all var(--transition);
}

.contact-item:hover {
  background: var(--bg-white);
  border-color: rgba(37, 99, 235, 0.2);
  box-shadow: var(--shadow-md);
}

.contact-item .icon {
  width: 48px; height: 48px;
  background: rgba(37, 99, 235, 0.08);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  flex-shrink: 0;
  font-size: 1.25rem;
}

.contact-item h4 { font-weight: 600; margin-bottom: 2px; }
.contact-item p { font-size: 0.85rem; color: var(--text-muted); }

/* Contact Form */
.contact-form {
  background: var(--bg-page);
  padding: 40px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

.form-group { margin-bottom: 18px; }

.form-group label {
  display: block;
  font-size: 0.84rem;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 6px;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 13px 16px;
  font-size: 0.92rem;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  background: var(--bg-white);
  color: var(--text-dark);
  font-family: inherit;
  transition: all var(--transition);
  outline: none;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.08);
}

.form-group textarea { resize: vertical; min-height: 120px; }

.form-submit {
  width: 100%;
  padding: 15px;
  font-size: 1rem;
  font-weight: 600;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: all var(--transition);
  box-shadow: 0 4px 16px rgba(37, 99, 235, 0.25);
}

.form-submit:hover {
  box-shadow: 0 6px 24px rgba(37, 99, 235, 0.4);
  transform: translateY(-1px);
}

/* --- Footer --- */
.footer {
  background: #070c18;
  color: rgba(255,255,255,0.45);
  padding: 64px 0 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand h3 { color: #fff; font-size: 1.15rem; margin-bottom: 14px; }
.footer-brand p { font-size: 0.85rem; line-height: 1.75; }

.footer-links h4 { color: #fff; font-size: 0.9rem; margin-bottom: 18px; font-weight: 600; }

.footer-links a {
  display: block;
  font-size: 0.84rem;
  color: rgba(255,255,255,0.35);
  padding: 5px 0;
  transition: all var(--transition);
}

.footer-links a:hover { color: var(--primary-glow); padding-left: 6px; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.05);
  padding-top: 24px;
  text-align: center;
  font-size: 0.8rem;
}

/* --- Scroll to top --- */
.scroll-top {
  position: fixed;
  bottom: 32px; right: 32px;
  width: 48px; height: 48px;
  background: var(--primary);
  color: #fff;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border: none;
  box-shadow: 0 4px 16px rgba(37, 99, 235, 0.3);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
  z-index: 999;
}

.scroll-top.visible { opacity: 1; visibility: visible; }
.scroll-top:hover {
  background: var(--primary-dark);
  box-shadow: 0 6px 24px rgba(37, 99, 235, 0.5);
  transform: translateY(-2px);
}

/* --- Toast --- */
.toast {
  position: fixed;
  top: 96px; right: 28px;
  background: var(--primary);
  color: #fff;
  padding: 16px 28px;
  border-radius: 10px;
  font-weight: 500;
  font-size: 0.9rem;
  box-shadow: 0 8px 32px rgba(37, 99, 235, 0.35);
  z-index: 2000;
  transform: translateX(120%);
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.toast.show { transform: translateX(0); }

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

  .hero .container {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-content .hero-subtitle { margin-left: auto; margin-right: auto; }
  .hero-buttons { justify-content: center; }
  .hero-stats { justify-content: center; }
  .hero-visual { display: none; }
  .hero-content h1 { font-size: 2.5rem; }
}

@media (max-width: 768px) {
  h1 { font-size: 2.2rem; }
  h2 { font-size: 1.8rem; }

  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: 0; right: 0;
    background: rgba(11, 17, 33, 0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    padding: 20px;
    gap: 4px;
    border-bottom: 1px solid rgba(255,255,255,0.06);
    transform: translateY(-120%);
    transition: transform var(--transition);
    z-index: 999;
  }

  .nav-links.open { transform: translateY(0); }
  .nav-links a { width: 100%; padding: 12px 16px; }
  .nav-toggle { display: flex; }

  .about-grid, .contact-grid { grid-template-columns: 1fr; gap: 40px; }
  .product-grid { grid-template-columns: 1fr 1fr; gap: 16px; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }

  .service-highlight {
    padding: 36px 28px;
  }
  .service-highlight-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .hero-content h1 { font-size: 2rem; }
}

@media (max-width: 480px) {
  .product-grid { grid-template-columns: 1fr; }
  .hero-stats { flex-direction: column; gap: 24px; align-items: center; }
  .hero-buttons { flex-direction: column; }
  .about-features { grid-template-columns: 1fr; }
  .service-highlight-grid { grid-template-columns: 1fr; }
}

/* --- Animations --- */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.65s ease, transform 0.65s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }