/* ===== 基础重置与变量 ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --clr-bg: #0a0e27;
  --clr-bg-alt: #0f1435;
  --clr-surface: #141a3a;
  --clr-surface-hover: #1c2358;
  --clr-border: rgba(255,255,255,0.06);
  --clr-text: #e8edff;
  --clr-text-secondary: #8892b0;
  --clr-accent: #00d4ff;
  --clr-accent-dim: rgba(0,212,255,0.08);
  --clr-warm: #f59e0b;
  --clr-warm-dim: rgba(245,158,11,0.08);
  --clr-purple: #6366f1;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-cn: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --nav-height: 72px;
  --max-width: 1200px;
  --radius: 12px;
  --radius-lg: 20px;
}
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-cn);
  background: var(--clr-bg);
  color: var(--clr-text);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; }
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== 导航 ===== */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-height);
  z-index: 1000;
  background: rgba(10,14,39,0.75);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--clr-border);
  transition: background 0.3s, box-shadow 0.3s;
}
.navbar.scrolled { background: rgba(10,14,39,0.92); box-shadow: 0 2px 40px rgba(0,0,0,0.4); }
.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}
.logo {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-sans);
  font-size: 1.6rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, #fff 30%, var(--clr-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.logo span { color: var(--clr-accent); -webkit-text-fill-color: var(--clr-accent); }
.logo-icon {
  display: block;
  flex-shrink: 0;
}
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--clr-text-secondary);
  transition: color 0.25s;
  position: relative;
}
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px; left: 0;
  width: 0; height: 2px;
  background: var(--clr-accent);
  transition: width 0.3s;
}
.nav-links a:hover { color: #fff; }
.nav-links a:hover::after { width: 100%; }
.nav-cta {
  padding: 10px 24px;
  border-radius: 99px;
  background: linear-gradient(135deg, var(--clr-accent), #0090ff);
  color: #fff !important;
  font-weight: 600;
  transition: transform 0.25s, box-shadow 0.25s;
}
.nav-cta::after { display: none !important; }
.nav-cta:hover { transform: translateY(-1px); box-shadow: 0 8px 30px rgba(0,212,255,0.3); }
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.hamburger span {
  display: block;
  width: 24px; height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: 0.3s;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: var(--nav-height);
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 20% 30%, rgba(0,212,255,0.08) 0%, transparent 70%),
    radial-gradient(ellipse 60% 50% at 80% 70%, rgba(99,102,241,0.06) 0%, transparent 60%),
    radial-gradient(ellipse 50% 40% at 50% 10%, rgba(245,158,11,0.04) 0%, transparent 50%);
  z-index: 0;
}
.hero-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(255,255,255,0.03) 1px, transparent 0);
  background-size: 32px 32px;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 0%, var(--clr-bg) 100%);
  z-index: 1;
}
.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 80px 0 60px;
}
.hero-badge {
  display: inline-block;
  padding: 6px 20px;
  border-radius: 99px;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--clr-accent);
  background: var(--clr-accent-dim);
  border: 1px solid rgba(0,212,255,0.15);
  margin-bottom: 24px;
}
.hero-title {
  font-family: var(--font-sans);
  font-size: clamp(2.6rem, 6vw, 4.5rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}
.accent-text { color: var(--clr-accent); }
.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.25rem);
  color: var(--clr-text-secondary);
  max-width: 600px;
  margin: 0 auto 36px;
  line-height: 1.8;
}
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 99px;
  font-family: var(--font-cn);
  font-size: 1rem;
  font-weight: 600;
  transition: transform 0.25s, box-shadow 0.25s, background 0.25s;
  border: none;
  cursor: pointer;
}
.btn-primary {
  background: linear-gradient(135deg, var(--clr-accent), #0090ff);
  color: #fff;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 40px rgba(0,212,255,0.35); }
.btn-outline {
  background: transparent;
  color: var(--clr-text);
  border: 1.5px solid rgba(255,255,255,0.15);
}
.btn-outline:hover { border-color: var(--clr-accent); color: var(--clr-accent); transform: translateY(-2px); }
.btn-block { width: 100%; justify-content: center; }

/* ===== Hero Stats ===== */
.hero-stats {
  display: flex;
  justify-content: center;
  gap: 48px;
  margin-top: 60px;
  flex-wrap: wrap;
}
.stat-item { text-align: center; }
.stat-number {
  display: block;
  font-family: var(--font-sans);
  font-size: 2.2rem;
  font-weight: 800;
  color: #fff;
  line-height: 1.2;
}
.stat-label {
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
}
/* Scroll indicator */
.scroll-indicator {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2;
  width: 24px; height: 36px;
  border: 2px solid rgba(255,255,255,0.2);
  border-radius: 12px;
  display: flex;
  justify-content: center;
  padding-top: 6px;
}
.scroll-indicator span {
  width: 3px; height: 8px;
  background: var(--clr-accent);
  border-radius: 3px;
  animation: scrollBounce 2s infinite;
}
@keyframes scrollBounce {
  0%, 100% { transform: translateY(0); opacity: 1; }
  50% { transform: translateY(8px); opacity: 0.3; }
}

/* ===== 通用 Section ===== */
.section {
  padding: 120px 0;
}
.section-dark {
  background: var(--clr-bg-alt);
  position: relative;
}
.section-dark::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--clr-accent), transparent);
  opacity: 0.15;
}
.section-header {
  text-align: center;
  margin-bottom: 64px;
}
.section-tag {
  display: inline-block;
  padding: 4px 16px;
  border-radius: 99px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--clr-accent);
  background: var(--clr-accent-dim);
  border: 1px solid rgba(0,212,255,0.1);
  margin-bottom: 16px;
}
.section-title {
  font-family: var(--font-sans);
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 16px;
  background: linear-gradient(135deg, #fff 40%, var(--clr-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.section-desc {
  font-size: 1.1rem;
  color: var(--clr-text-secondary);
  max-width: 520px;
  margin: 0 auto;
}

/* ===== 服务 ===== */
.service-group { margin-bottom: 64px; }
.service-group:last-child { margin-bottom: 0; }
.service-group-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 32px;
  color: #fff;
}
.service-group-icon { font-size: 1.4rem; }
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.service-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}
.service-card:hover {
  transform: translateY(-4px);
  border-color: rgba(0,212,255,0.15);
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}
.service-icon {
  width: 56px; height: 56px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  background: var(--icon-bg);
}
.service-card h4 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 10px;
  color: #fff;
}
.service-card p {
  font-size: 0.9rem;
  color: var(--clr-text-secondary);
  line-height: 1.7;
}

/* ===== 关于我们 ===== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.about-paragraph {
  color: var(--clr-text-secondary);
  font-size: 1rem;
  margin-bottom: 20px;
  line-height: 1.8;
}
.about-paragraph strong { color: var(--clr-text); }
.about-values {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 28px;
}
.value-item {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--clr-text);
}
.about-card-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.about-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 28px 20px;
  text-align: center;
  transition: transform 0.3s, border-color 0.3s;
}
.about-card:hover { transform: translateY(-2px); border-color: rgba(0,212,255,0.15); }
.about-card-number {
  display: block;
  font-family: var(--font-sans);
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--clr-accent);
  margin-bottom: 4px;
}
.about-card-label {
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
}

/* ===== 团队 ===== */
.team-section { margin-top: 80px; }
.team-heading {
  text-align: center;
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 40px;
  color: #fff;
}
.team-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.team-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-align: center;
  transition: transform 0.3s;
}
.team-card:hover { transform: translateY(-4px); }
.team-avatar {
  width: 64px; height: 64px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  font-family: var(--font-sans);
  font-size: 1.1rem;
  font-weight: 700;
  color: #fff;
}
.team-card h4 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 2px;
  color: #fff;
}
.team-role {
  display: block;
  font-size: 0.8rem;
  color: var(--clr-accent);
  margin-bottom: 10px;
}
.team-card p {
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
}

/* ===== 案例 ===== */
.portfolio-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.portfolio-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: transform 0.3s, box-shadow 0.3s;
}
.portfolio-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}
.portfolio-image {
  height: 200px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.portfolio-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  opacity: 0.4;
}
.portfolio-placeholder span {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.4);
}
.portfolio-body { padding: 24px; }
.portfolio-tag {
  display: inline-block;
  padding: 3px 12px;
  border-radius: 99px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--clr-accent);
  background: var(--clr-accent-dim);
  border: 1px solid rgba(0,212,255,0.1);
  margin-bottom: 12px;
}
.tag-dev { color: var(--clr-warm); background: var(--clr-warm-dim); border-color: rgba(245,158,11,0.1); }
.portfolio-body h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: #fff;
}
.portfolio-body p {
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
  margin-bottom: 16px;
}
.portfolio-metrics {
  display: flex;
  gap: 16px;
  font-size: 0.8rem;
  color: var(--clr-text-secondary);
}
.portfolio-metrics strong { color: var(--clr-accent); }

/* ===== 联系 ===== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.3fr;
  gap: 60px;
}
.contact-info { display: flex; flex-direction: column; gap: 28px; }
.contact-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}
.contact-item svg { flex-shrink: 0; margin-top: 2px; }
.contact-item h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 2px;
  color: #fff;
}
.contact-item p { color: var(--clr-text-secondary); font-size: 0.9rem; }
.contact-social { margin-top: 8px; }
.contact-social p { font-size: 0.9rem; color: var(--clr-text-secondary); margin-bottom: 12px; }
.social-links { display: flex; gap: 12px; }
.social-links a {
  width: 40px; height: 40px;
  border-radius: 10px;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--clr-text-secondary);
  transition: all 0.25s;
}
.social-links a:hover { color: var(--clr-accent); border-color: var(--clr-accent); background: var(--clr-accent-dim); }

/* Contact Form */
.contact-form {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: 40px;
}
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
.form-group { margin-bottom: 20px; }
.form-group label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--clr-text);
}
.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border-radius: 10px;
  border: 1px solid var(--clr-border);
  background: rgba(255,255,255,0.03);
  color: var(--clr-text);
  font-family: var(--font-cn);
  font-size: 0.95rem;
  outline: none;
  transition: border-color 0.25s, background 0.25s;
}
.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--clr-accent);
  background: rgba(0,212,255,0.04);
}
.form-group input::placeholder,
.form-group textarea::placeholder { color: rgba(255,255,255,0.2); }
.form-group textarea { resize: vertical; min-height: 100px; }

/* ===== 页脚 ===== */
.footer {
  background: var(--clr-bg);
  border-top: 1px solid var(--clr-border);
  padding: 60px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand .logo {
  display: inline-flex;
  align-items: center;
  gap: 8px; font-size: 1.4rem; }
.footer-brand p {
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
  margin-top: 12px;
  max-width: 280px;
  line-height: 1.7;
}
.footer-links h4 {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 16px;
  color: #fff;
}
.footer-links a,
.footer-links p {
  display: block;
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
  margin-bottom: 8px;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--clr-accent); }
.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--clr-border);
  text-align: center;
  font-size: 0.8rem;
  color: rgba(255,255,255,0.25);
}

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .services-grid { grid-template-columns: repeat(2, 1fr); }
  .portfolio-grid { grid-template-columns: repeat(2, 1fr); }
  .team-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: var(--nav-height); left: 0; right: 0;
    flex-direction: column;
    background: rgba(10,14,39,0.97);
    backdrop-filter: blur(20px);
    padding: 24px;
    gap: 20px;
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: 0.35s;
    border-bottom: 1px solid var(--clr-border);
  }
  .nav-links.open { transform: translateY(0); opacity: 1; pointer-events: auto; }
  .hamburger { display: flex; }
  .hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
  .hamburger.active span:nth-child(2) { opacity: 0; }
  .hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

  .hero-title { font-size: 2.2rem; }
  .hero-stats { gap: 24px; }
  .stat-number { font-size: 1.6rem; }

  .services-grid { grid-template-columns: 1fr; }
  .service-group-title { font-size: 1.25rem; }

  .about-grid { grid-template-columns: 1fr; gap: 40px; }
  .team-grid { grid-template-columns: repeat(2, 1fr); }
  .portfolio-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }

  .section { padding: 80px 0; }
  .contact-form { padding: 28px; }
}
@media (max-width: 480px) {
  .team-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .btn { justify-content: center; }
}

/* ===== 动画 ===== */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}
/* ===== Hero 增强：粒子动画 ===== */
.hero-particles {
  position: absolute;
  inset: 0;
  z-index: 0;
  overflow: hidden;
  pointer-events: none;
}
.hero-particle {
  position: absolute;
  width: 3px; height: 3px;
  background: var(--clr-accent);
  border-radius: 50%;
  opacity: 0;
  animation: particleFloat 12s infinite;
}
@keyframes particleFloat {
  0%   { transform: translateY(100vh) scale(0); opacity: 0; }
  10%  { opacity: 0.5; }
  90%  { opacity: 0.3; }
  100% { transform: translateY(-10vh) scale(1); opacity: 0; }
}

/* ===== 语言切换器 ===== */
.lang-switcher {
  display: flex;
  align-items: center;
  margin-right: 8px;
}
.lang-select {
  padding: 5px 10px;
  border-radius: 6px;
  border: 1px solid rgba(255,255,255,0.1);
  background: var(--clr-surface);
  color: var(--clr-text-secondary);
  font-family: var(--font-cn);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  line-height: 1.4;
  outline: none;
  min-width: 80px;
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M0 0l5 6 5-6z' fill='%238892b0'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 8px center;
  padding-right: 26px;
}
.lang-select:hover, .lang-select:focus {
  border-color: rgba(0,212,255,0.2);
  color: #fff;
}
.lang-select option {
  background: var(--clr-bg-alt);
  color: var(--clr-text);
}