/* ===== Reset & Base ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Noto Sans SC', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.6;
  color: #1f2937;
  background: #fff;
}

/* ===== Layout ===== */
.container { max-width: 1280px; margin: 0 auto; padding: 0 1rem; }
@media (min-width: 640px)  { .container { padding: 0 1.5rem; } }
@media (min-width: 1024px) { .container { padding: 0 2rem; } }

/* ===== CSS Variables (Blue-Teal Gradient Theme) ===== */
:root {
  --color-a: #0369a1;   /* blue-700 */
  --color-b: #0891b2;   /* cyan-600 */
  --color-c: #0d9488;   /* teal-600 */
  --grad-main: linear-gradient(135deg, #0c4a6e 0%, #075985 40%, #0e7490 70%, #0d9488 100%);
  --grad-accent: linear-gradient(90deg, #0369a1, #0891b2, #0d9488);
  --grad-text: linear-gradient(135deg, #0369a1, #0891b2);
}

/* ===== Utility ===== */
.gradient-text {
  background: var(--grad-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.gradient-overlay { background: var(--grad-main); }

/* Tech Grid Pattern */
.tech-grid {
  background-image:
    linear-gradient(rgba(14,116,144,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(14,116,144,0.06) 1px, transparent 1px);
  background-size: 60px 60px;
}
.tech-grid-light {
  background-image:
    linear-gradient(rgba(14,116,144,0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(14,116,144,0.07) 1px, transparent 1px);
  background-size: 40px 40px;
}

/* Decorative Blobs */
.blob { position: absolute; border-radius: 50%; filter: blur(80px); pointer-events: none; }
.blob-teal { background: rgba(13,148,136,0.12); }
.blob-cyan { background: rgba(8,145,178,0.12); }

/* ===== Animations ===== */
@keyframes float       { 0%, 100% { transform: translateY(0); }   50% { transform: translateY(-20px); } }
@keyframes float-slow  { 0%, 100% { transform: translateY(0); }   50% { transform: translateY(-10px); } }
@keyframes pulse-glow  { 0%, 100% { opacity: 0.5; }               50% { opacity: 1; } }
@keyframes bounce      { 0%, 100% { transform: translateY(0); }   50% { transform: translateY(-10px); } }
@keyframes fadeInUp    { from { opacity: 0; transform: translateY(30px); } to { opacity: 1; transform: translateY(0); } }
@keyframes spin        { from { transform: rotate(0deg); }        to { transform: rotate(360deg); } }

.animate-float       { animation: float 6s ease-in-out infinite; }
.animate-float-slow  { animation: float-slow 8s ease-in-out infinite; }
.animate-pulse-glow  { animation: pulse-glow 4s ease-in-out infinite; }
.animate-bounce      { animation: bounce 2s ease-in-out infinite; }
.fade-in-up          { animation: fadeInUp 0.8s ease-out forwards; }

/* ===== Navbar ===== */
.navbar {
  position: fixed; top: 0; left: 0; right: 0;
  z-index: 1000;
  transition: all 0.35s;
  padding: 1rem 0;
}
.navbar.scrolled {
  background: rgba(255,255,255,0.96);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 3px rgba(0,0,0,0.12);
  padding: 0.65rem 0;
}
.navbar.scrolled .nav-link   { color: #374151; }
.navbar.scrolled .nav-link:hover { color: #0369a1; }
.navbar.scrolled .mobile-menu-btn { color: #374151; }

.nav-link {
  color: white;
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  transition: color 0.3s;
  padding: 0.5rem 0.75rem;
}
.nav-link:hover { color: #7dd3fc; }
.nav-link.active { color: #7dd3fc; }

/* Sub-pages: navbar has blue-teal bg by default */
.navbar-teal {
  background: linear-gradient(90deg, rgba(7,89,133,0.97), rgba(14,116,144,0.97));
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 3px rgba(0,0,0,0.2);
}
.navbar-teal .nav-link { color: rgba(255,255,255,0.9); }
.navbar-teal .mobile-menu-btn { color: rgba(255,255,255,0.9); }

/* Logo (two versions) */
.logo-light { display: block; }   /* white version, shown on dark hero */
.logo-dark  { display: none;  }   /* colored version, shown on scrolled navbar */
.navbar.scrolled .logo-light { display: none; }
.navbar.scrolled .logo-dark  { display: block; }

/* On sub-pages (navbar-teal class), always show logo-light */
.navbar-teal .logo-light { display: block !important; }
.navbar-teal .logo-dark  { display: none  !important; }

/* Mobile menu */
.mobile-menu-btn {
  display: block;
  background: none;
  border: none;
  color: white;
  cursor: pointer;
  padding: 0.5rem;
}
@media (min-width: 768px) { .mobile-menu-btn { display: none; } }

.nav-links { display: none; }
@media (min-width: 768px) { .nav-links { display: flex; align-items: center; gap: 0.5rem; } }

.nav-links-mobile {
  display: none;
  position: absolute;
  top: 100%; left: 0; right: 0;
  background: white;
  padding: 1rem;
  box-shadow: 0 10px 15px -3px rgba(0,0,0,0.1);
}
.nav-links-mobile.active { display: block; }
.nav-links-mobile a {
  display: block;
  padding: 0.75rem;
  color: #374151;
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: 0.5rem;
}
.nav-links-mobile a:hover { background: #f0f9ff; color: #0369a1; }

/* Logo SVG */
.logo-svg { width: 151px; height: 76px; }

/* ===== Section Shared ===== */
.section { padding: 6rem 0; }
@media (min-width: 640px) { .section { padding: 8rem 0; } }

.section-header { text-align: center; max-width: 48rem; margin: 0 auto 4rem; }
.section-tag {
  display: inline-block;
  padding: 0.375rem 1rem;
  background: #eff6ff;
  color: #0369a1;
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: 9999px;
  margin-bottom: 1rem;
  border: 1px solid #bfdbfe;
}
.section-title { font-size: 1.875rem; font-weight: 700; color: #111827; margin-bottom: 1.5rem; }
@media (min-width: 640px)  { .section-title { font-size: 2.25rem; } }
@media (min-width: 1024px) { .section-title { font-size: 3rem; } }
.section-desc { font-size: 1.125rem; color: #6b7280; line-height: 1.75; }

/* ===== Buttons ===== */
.btn-primary {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 1rem 2rem;
  background: white; color: #075985;
  font-weight: 600; border-radius: 0.75rem;
  text-decoration: none;
  box-shadow: 0 10px 15px -3px rgba(0,0,0,0.1);
  transition: all 0.3s;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 20px 25px -5px rgba(0,0,0,0.1); }

.btn-secondary {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 1rem 2rem;
  background: rgba(255,255,255,0.1);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255,255,255,0.25);
  color: white; font-weight: 600; border-radius: 0.75rem;
  text-decoration: none; transition: all 0.3s;
}
.btn-secondary:hover { background: rgba(255,255,255,0.2); transform: translateY(-2px); }

.btn-accent {
  display: inline-flex; align-items: center;
  padding: 0.75rem 2rem;
  background: var(--grad-accent);
  color: white; font-weight: 600; border-radius: 0.75rem;
  text-decoration: none;
  box-shadow: 0 10px 15px -3px rgba(3,105,161,0.25);
  transition: all 0.3s; flex-shrink: 0;
}
.btn-accent:hover { transform: translateY(-2px); box-shadow: 0 20px 25px -5px rgba(3,105,161,0.35); }

/* ===== Page Hero (sub-pages) ===== */
.page-hero {
  padding: 8rem 0 4rem;
  background: var(--grad-main);
  position: relative; overflow: hidden;
}
.page-hero-bg {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(14,116,144,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(14,116,144,0.06) 1px, transparent 1px);
  background-size: 60px 60px;
}
.page-hero-title { font-size: 2.25rem; font-weight: 700; color: white; margin-bottom: 1rem; }
@media (min-width: 640px) { .page-hero-title { font-size: 3rem; } }
.page-hero-subtitle { font-size: 1.125rem; color: rgba(255,255,255,0.75); }
.breadcrumb { display: flex; align-items: center; gap: 0.5rem; font-size: 0.875rem; color: rgba(255,255,255,0.6); margin-bottom: 1.5rem; }
.breadcrumb a { color: rgba(255,255,255,0.6); text-decoration: none; transition: color 0.3s; }
.breadcrumb a:hover { color: #5eead4; }
.breadcrumb-sep { color: rgba(255,255,255,0.4); }

/* ===== Footer ===== */
.footer { background: #0c1524; color: #9ca3af; margin-top: 2rem; }
.footer-top { height: 2px; background: linear-gradient(90deg, transparent, #0369a1, #0891b2, #0d9488, transparent); }
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 2.5rem; padding: 4rem 0; }
@media (min-width: 768px)  { .footer-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .footer-grid { grid-template-columns: 2fr 1fr 1fr; } }

.footer-brand { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 1rem; }
.footer-logo {
  width: 2.5rem; height: 2.5rem; border-radius: 0.5rem;
  background: linear-gradient(135deg, #075985, #0e7490);
  display: flex; align-items: center; justify-content: center;
}
.footer-logo-text { color: white; font-weight: 700; font-size: 1.125rem; }
.footer-company { color: white; font-weight: 600; }
.footer-company-en { font-size: 0.75rem; color: #6b7280; margin-top: 0.125rem; }
.footer-desc { font-size: 0.875rem; line-height: 1.625; max-width: 28rem; margin-bottom: 1.5rem; }
.footer-status { display: flex; align-items: center; gap: 0.75rem; }
.footer-status-dot { width: 0.5rem; height: 0.5rem; background: #22d3ee; border-radius: 50%; animation: pulse-glow 2s infinite; }
.footer-status-text { font-size: 0.875rem; color: #6b7280; }
.footer-title { color: white; font-weight: 600; margin-bottom: 1rem; }
.footer-links { list-style: none; }
.footer-links li { margin-bottom: 0.625rem; }
.footer-links a { color: #9ca3af; text-decoration: none; font-size: 0.875rem; transition: color 0.3s; }
.footer-links a:hover { color: #7dd3fc; }

.footer-bottom {
  padding: 1.5rem 0;
  border-top: 1px solid #1e293b;
  display: flex; flex-direction: column; align-items: center; gap: 0.5rem;
}
@media (min-width: 640px) { .footer-bottom { flex-direction: row; justify-content: space-between; } }
.footer-copyright { font-size: 0.75rem; color: #6b7280; }

/* ICP & 公安备案 — 紧接版权文字后面，不单独起行 */
.footer-icp {
  display: inline-flex; flex-wrap: wrap; align-items: center; gap: 0.5rem;
}
.footer-icp a, .footer-icp span {
  font-size: 0.75rem; color: #4b5563;
  text-decoration: none; transition: color 0.3s;
  display: inline-flex; align-items: center; gap: 0.25rem;
}
.footer-icp a:hover { color: #7dd3fc; }
.footer-icp-icon { width: 14px; height: 14px; flex-shrink: 0; }

.footer-top-btn {
  display: flex; align-items: center; gap: 0.5rem;
  padding: 0.5rem 1rem;
  background: #1e293b; color: #9ca3af;
  border: none; border-radius: 0.5rem;
  font-size: 0.875rem; cursor: pointer; transition: all 0.3s;
}
.footer-top-btn:hover { background: #334155; color: white; }

/* ===== Loading / Empty States ===== */
.loading { text-align: center; padding: 4rem; }
.loading-spinner {
  width: 40px; height: 40px;
  border: 3px solid #f3f4f6;
  border-top-color: #0369a1;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 0 auto 1rem;
}
.empty-state { text-align: center; padding: 4rem; color: #9ca3af; }
.error-state  { text-align: center; padding: 6rem 0; }