/* ========== 基础变量 ========== */
:root {
  --primary: #2563EB;
  --primary-dark: #1D4ED8;
  --primary-light: #DBEAFE;
  --accent: #F59E0B;
  --accent-light: #FEF3C7;
  --dark: #0F172A;
  --gray-900: #1E293B;
  --gray-700: #334155;
  --gray-500: #64748B;
  --gray-300: #CBD5E1;
  --gray-100: #F1F5F9;
  --white: #FFFFFF;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
  --shadow-lg: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);
  --shadow-xl: 0 25px 50px -12px rgba(0,0,0,0.25);
  --transition: all 0.3s ease;
}

/* ========== Reset ========== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--gray-700);
  line-height: 1.7;
  background: var(--white);
  overflow-x: hidden;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

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

/* ========== 导航 ========== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: var(--transition);
}
.navbar.scrolled {
  border-bottom-color: var(--gray-300);
  box-shadow: var(--shadow);
}
.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--dark);
}
.logo-icon { font-size: 1.5rem; }
.logo-text sup { font-size: 0.6em; color: var(--primary); }
.logo-cn { font-size: 0.7em; font-weight: 400; color: var(--gray-500); margin-left: 6px; letter-spacing: 1px; }
.logo-en { font-weight: 400; font-size: 0.75em; color: var(--gray-500); margin-left: 4px; letter-spacing: 0.5px; }
/* Chinese subtitle helpers */
.hero-cn { font-size: 0.8rem; opacity: 0.45; display: block; margin-top: 12px; letter-spacing: 2px; font-family: 'Noto Sans SC', sans-serif; }
.price-tier-cn { font-size: 0.75rem; color: var(--gray-500); margin-bottom: 4px; letter-spacing: 1px; font-family: 'Noto Sans SC', sans-serif; }
.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}
.nav-links a {
  font-size: 0.95rem;
  color: var(--gray-700);
  transition: var(--transition);
  font-weight: 500;
}
.nav-links a:hover { color: var(--primary); }
.lang-switch {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1.5px solid var(--gray-300);
  border-radius: 50%;
  font-size: 0.8rem !important;
  font-weight: 600 !important;
  color: var(--gray-700) !important;
  transition: var(--transition);
}
.lang-switch:hover {
  border-color: var(--primary);
  color: var(--primary) !important;
  background: var(--primary-light);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--dark);
  transition: var(--transition);
  border-radius: 2px;
}

/* ========== 按钮 ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  transition: var(--transition);
  cursor: pointer;
  border: 2px solid transparent;
}
.btn-primary {
  background: var(--primary);
  color: var(--white);
  border-color: var(--primary);
}
.btn-primary:hover {
  background: var(--primary-dark);
  border-color: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}
.btn-outline {
  background: transparent;
  color: var(--primary);
  border-color: var(--primary);
}
.btn-outline:hover {
  background: var(--primary);
  color: var(--white);
  transform: translateY(-2px);
}
.btn-nav {
  padding: 8px 20px;
  font-size: 0.875rem;
}
.btn-lg {
  padding: 16px 36px;
  font-size: 1.05rem;
}

/* ========== Hero ========== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 72px;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #0F172A 0%, #1E3A5F 40%, #2563EB 100%);
  z-index: 0;
}
.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 70% 20%, rgba(37,99,235,0.3) 0%, transparent 60%),
              radial-gradient(ellipse at 30% 80%, rgba(245,158,11,0.15) 0%, transparent 50%);
}
.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  color: var(--white);
  padding: 60px 0;
}
.hero-badge {
  display: inline-block;
  padding: 6px 20px;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 100px;
  font-size: 0.85rem;
  margin-bottom: 24px;
  backdrop-filter: blur(4px);
}
.hero h1 {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: 12px;
  letter-spacing: -1px;
}
.hero-keyword {
  background: linear-gradient(135deg, #F59E0B, #FBBF24);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-slogan {
  font-size: 1.15rem;
  opacity: 0.55;
  margin-bottom: 20px;
  letter-spacing: 6px;
  font-weight: 300;
}
.hero-sub {
  font-size: 1.15rem;
  opacity: 0.9;
  margin-bottom: 40px;
  line-height: 1.8;
}
.hero-sub strong {
  color: var(--accent);
  font-weight: 700;
}
.hero-stats {
  display: flex;
  justify-content: center;
  gap: 60px;
  margin-bottom: 48px;
}
.stat { text-align: center; }
.stat-num {
  display: block;
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--accent);
}
.stat-label {
  font-size: 0.9rem;
  opacity: 0.8;
}
.hero-actions {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}
.hero .btn-outline {
  color: var(--white);
  border-color: rgba(255,255,255,0.4);
}
.hero .btn-outline:hover {
  background: var(--white);
  color: var(--primary);
  border-color: var(--white);
}

/* ========== 通用 Section ========== */
.section {
  padding: 100px 0;
}
.section-title {
  text-align: center;
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--dark);
  margin-bottom: 12px;
}
.highlight {
  color: var(--primary);
}
.section-desc {
  text-align: center;
  font-size: 1.1rem;
  color: var(--gray-500);
  margin-bottom: 60px;
}

/* ========== 痛点 ========== */
.pain-points { background: var(--gray-100); }
.pain-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.pain-card {
  background: var(--white);
  padding: 36px 28px;
  border-radius: var(--radius);
  text-align: center;
  box-shadow: var(--shadow);
  transition: var(--transition);
}
.pain-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.pain-emoji { font-size: 2.5rem; margin-bottom: 16px; }
.pain-card h3 {
  font-size: 1.1rem;
  color: var(--dark);
  margin-bottom: 10px;
}
.pain-card p {
  font-size: 0.9rem;
  color: var(--gray-500);
  line-height: 1.6;
}

/* ========== 核心能力 ========== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.feature-card {
  background: var(--white);
  border: 1px solid var(--gray-300);
  padding: 32px 24px;
  border-radius: var(--radius);
  text-align: center;
  transition: var(--transition);
}
.feature-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.feature-card.featured {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-color: var(--primary);
  color: var(--white);
}
.feature-card.featured h3 { color: var(--white); }
.feature-card.featured p { color: rgba(255,255,255,0.85); }
.feature-icon {
  font-size: 2rem;
  margin-bottom: 14px;
}
.feature-card h3 {
  font-size: 1rem;
  color: var(--dark);
  margin-bottom: 8px;
  font-weight: 600;
}
.feature-card p {
  font-size: 0.85rem;
  color: var(--gray-500);
  line-height: 1.5;
}

/* ========== 架构 ========== */
.architecture { background: var(--dark); color: var(--white); }
.architecture .section-title { color: var(--white); }
.architecture .section-desc { color: var(--gray-300); }
.arch-layers {
  max-width: 700px;
  margin: 0 auto;
}
.arch-layer {
  display: flex;
  align-items: stretch;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.layer-label {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  padding: 20px 16px;
  font-weight: 700;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  justify-content: center;
  letter-spacing: 4px;
}
.layer-content {
  padding: 28px 32px;
  flex: 1;
}
.layer-content h3 {
  font-size: 1.15rem;
  margin-bottom: 8px;
  font-weight: 700;
}
.layer-content p {
  font-size: 0.9rem;
  opacity: 0.85;
  line-height: 1.6;
}
.layer-top .layer-label { background: var(--accent); color: var(--dark); }
.layer-top .layer-content { background: var(--accent-light); color: var(--dark); }
.layer-mid .layer-label { background: var(--primary); color: var(--white); }
.layer-mid .layer-content { background: var(--primary-light); color: var(--dark); }
.layer-bottom .layer-label { background: #10B981; color: var(--white); }
.layer-bottom .layer-content { background: #D1FAE5; color: var(--dark); }
.arch-connector {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 12px 0;
}
.connector-line {
  width: 2px;
  height: 20px;
  background: var(--gray-500);
}
.connector-text {
  font-size: 0.8rem;
  color: var(--gray-300);
  margin-top: 4px;
}

/* ========== 对比表 ========== */
.comparison { background: var(--gray-100); }
.compare-table-wrap { overflow-x: auto; }
.compare-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.compare-table th, .compare-table td {
  padding: 18px 24px;
  text-align: center;
  font-size: 0.95rem;
}
.compare-table thead th {
  background: var(--gray-900);
  color: var(--white);
  font-weight: 600;
}
.compare-table thead th.highlight-col {
  background: var(--primary);
}
.compare-table tbody tr { border-bottom: 1px solid var(--gray-100); }
.compare-table tbody tr:last-child { border-bottom: none; }
.compare-table td.highlight-col {
  background: var(--primary-light);
  color: var(--primary-dark);
  font-weight: 600;
}

/* ========== 价格 ========== */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: start;
}
.price-card {
  background: var(--white);
  border: 2px solid var(--gray-300);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
  text-align: center;
  transition: var(--transition);
  position: relative;
}
.price-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}
.price-featured {
  border-color: var(--primary);
  box-shadow: var(--shadow-xl);
  transform: scale(1.05);
}
.price-featured:hover { transform: scale(1.05) translateY(-4px); }
.price-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary);
  color: var(--white);
  padding: 4px 20px;
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 600;
  white-space: nowrap;
}
.price-tier {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 4px;
}
.price-for {
  font-size: 0.85rem;
  color: var(--gray-500);
  margin-bottom: 24px;
}
.price-amount { margin-bottom: 4px; }
.price-currency {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--dark);
  vertical-align: top;
}
.price-num {
  font-size: 3rem;
  font-weight: 900;
  color: var(--dark);
  line-height: 1;
}
.price-period {
  font-size: 1rem;
  color: var(--gray-500);
}
.price-monthly {
  font-size: 0.9rem;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 28px;
}
.price-features {
  text-align: left;
  margin-bottom: 32px;
}
.price-features li {
  padding: 8px 0;
  font-size: 0.9rem;
  border-bottom: 1px solid var(--gray-100);
}
.price-features li:last-child { border-bottom: none; }
.price-card .btn { width: 100%; }
.pricing-note {
  text-align: center;
  margin-top: 48px;
  font-size: 1rem;
  color: var(--gray-500);
  background: var(--accent-light);
  padding: 16px 24px;
  border-radius: var(--radius);
}

/* ========== 案例 ========== */
.cases { background: var(--gray-100); }
.cases-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}
.case-card {
  background: var(--white);
  padding: 36px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
}
.case-quote {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--gray-700);
  margin-bottom: 24px;
  position: relative;
  padding-left: 20px;
  border-left: 3px solid var(--primary);
}
.case-author {
  display: flex;
  align-items: center;
  gap: 12px;
}
.case-avatar {
  width: 48px;
  height: 48px;
  background: var(--primary-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}
.case-name { font-weight: 700; color: var(--dark); }
.case-info { font-size: 0.85rem; color: var(--gray-500); }

/* ========== 关于 ========== */
.about-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 60px;
  align-items: center;
}
.about-text h2 {
  font-size: 2rem;
  color: var(--dark);
  margin-bottom: 20px;
  text-align: left;
}
.about-text p {
  margin-bottom: 16px;
  line-height: 1.8;
}
.about-brands {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}
.brand-tag {
  background: var(--gray-100);
  padding: 6px 16px;
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 500;
}
.about-values {
  display: flex;
  flex-direction: column;
  gap: 28px;
}
.value-item {
  text-align: center;
  padding: 28px;
  background: var(--primary-light);
  border-radius: var(--radius);
}
.value-num {
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--primary);
}
.value-label {
  font-size: 0.9rem;
  color: var(--gray-700);
  margin-top: 4px;
}

/* ========== 联系 ========== */
.contact {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: var(--white);
}
.contact .section-title { color: var(--white); }
.contact .highlight { color: var(--accent); }
.contact .section-desc { color: rgba(255,255,255,0.8); }
.contact-grid {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 60px;
  flex-wrap: wrap;
}
.contact-item {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1rem;
  margin-bottom: 16px;
}
.contact-icon { font-size: 1.3rem; }
.contact-cta { text-align: center; }
.contact .btn-primary {
  background: var(--white);
  color: var(--primary);
  border-color: var(--white);
}
.contact .btn-primary:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--dark);
}
.contact-note {
  margin-top: 12px;
  font-size: 0.85rem;
  opacity: 0.8;
}

/* ========== 页脚 ========== */
.footer {
  background: var(--dark);
  color: var(--gray-300);
  padding: 60px 0 30px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-grid-5 {
  grid-template-columns: 1.5fr 0.8fr 1.5fr 1.2fr 1fr;
}
.footer-sub {
  display: block;
  font-size: 0.75rem;
  color: var(--gray-500);
  opacity: 0.7;
  margin-top: 1px;
}
.footer-brand .logo-text {
  color: var(--white);
  font-size: 1.2rem;
  font-weight: 700;
}
.footer-brand p {
  margin-top: 8px;
  font-size: 0.9rem;
}
.footer-links h4 {
  color: var(--white);
  font-size: 0.95rem;
  margin-bottom: 16px;
}
.footer-links a {
  display: block;
  font-size: 0.9rem;
  margin-bottom: 10px;
  color: var(--gray-500);
  transition: var(--transition);
}
.footer-links a:hover { color: var(--white); }
.footer-bottom {
  border-top: 1px solid var(--gray-700);
  padding-top: 24px;
  text-align: center;
  font-size: 0.85rem;
  color: var(--gray-500);
}

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
  .pain-grid { grid-template-columns: repeat(2, 1fr); }
  .features-grid { grid-template-columns: repeat(3, 1fr); }
  .pricing-grid { grid-template-columns: repeat(3, 1fr); gap: 16px; }
  .price-card { padding: 32px 20px; }
  .price-featured { transform: scale(1.02); }
  .price-featured:hover { transform: scale(1.02) translateY(-4px); }
  .footer-grid-5 { grid-template-columns: 1.5fr 1fr 1.5fr; }
}

@media (max-width: 768px) {
  .nav-toggle { display: flex; }
  .nav-links {
    display: none;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--white);
    flex-direction: column;
    padding: 24px;
    gap: 16px;
    box-shadow: var(--shadow-lg);
    border-top: 1px solid var(--gray-300);
  }
  .nav-links.active { display: flex; }
  
  .hero h1 { font-size: 2.25rem; }
  .hero-sub { font-size: 1.05rem; }
  .hero-stats { gap: 32px; }
  .stat-num { font-size: 2rem; }
  
  .section { padding: 60px 0; }
  .section-title { font-size: 1.75rem; }
  .section-desc { margin-bottom: 40px; }
  
  .pain-grid { grid-template-columns: 1fr 1fr; }
  .features-grid { grid-template-columns: 1fr 1fr; }
  .pricing-grid { grid-template-columns: 1fr; max-width: 400px; margin: 0 auto; }
  .price-featured { transform: none; }
  .price-featured:hover { transform: translateY(-4px); }
  .cases-grid { grid-template-columns: 1fr; }
  .about-grid { grid-template-columns: 1fr; gap: 40px; }
  .about-text h2 { text-align: center; }
  .about-values { flex-direction: row; }
  .footer-grid, .footer-grid-5 { grid-template-columns: 1fr 1fr; text-align: left; gap: 28px; }
  .footer-brand { grid-column: 1 / -1; text-align: center; }
  .contact-grid { flex-direction: column; }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 1.85rem; }
  .hero-stats { flex-direction: column; gap: 16px; }
  .pain-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr; }
  .about-values { flex-direction: column; }
  .compare-table th, .compare-table td { padding: 12px 10px; font-size: 0.8rem; }
  .btn-lg { padding: 14px 28px; font-size: 0.95rem; }
  .footer-grid, .footer-grid-5 { grid-template-columns: 1fr; text-align: center; }
}