/*
 * style.css — 全站共享样式
 *
 * 调色板
 *   主色 1：#00D9FF  (cyan)
 *   主色 2：#9C27FF  (purple)
 *   正文：  #2D3436
 *   卡片：  #FFFFFF
 *   页面底：#F7F7FB
 *   辅助灰：#636E72
 *
 * 字体栈：中英文兼容
 * 断点：  768px（移动端）、1024px（平板）
 */

/* ════════════════════════════════════════════
   全局 Reset 与基础
════════════════════════════════════════════ */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --cyan:        #00D9FF;
  --purple:      #9C27FF;
  --cyan-dark:   #00B8D9;
  --purple-dark: #7B1FA2;
  --text:        #2D3436;
  --text-light:  #636E72;
  --white:       #FFFFFF;
  --bg:          #F7F7FB;
  --card-bg:     #FFFFFF;
  --nav-height:  68px;
  --radius:      12px;
  --shadow-sm:   0 2px 8px rgba(0,0,0,.08);
  --shadow-md:   0 8px 32px rgba(0,0,0,.12);
  --shadow-lg:   0 20px 60px rgba(0,0,0,.16);
  --gradient:    linear-gradient(135deg, var(--cyan) 0%, var(--purple) 100%);
  --font:        'Segoe UI', Tahoma, Geneva, Verdana, -apple-system,
                 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --transition:  0.3s ease;
}

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

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  overflow-x: hidden;
}

img, svg {
  max-width: 100%;
  display: block;
}

a {
  text-decoration: none;
  color: inherit;
}

ul, ol {
  list-style: none;
}

/* ════════════════════════════════════════════
   工具类
════════════════════════════════════════════ */
.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 渐变文字 */
.gradient-text {
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* 小徽章标签 */
.badge {
  display: inline-block;
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 12px;
}

/* 可见性控制（IntersectionObserver 动画） */
.fade-up {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity .65s ease, transform .65s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* 延迟动画组 */
.fade-up:nth-child(2) { transition-delay: .1s; }
.fade-up:nth-child(3) { transition-delay: .2s; }
.fade-up:nth-child(4) { transition-delay: .3s; }

/* ════════════════════════════════════════════
   导航栏
════════════════════════════════════════════ */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--nav-height);
  z-index: 1000;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0, 217, 255, 0.12);
  transition: box-shadow var(--transition);
}

/* 滚动后加阴影（由 main.js 添加 .scrolled class） */
.site-nav.scrolled {
  box-shadow: 0 4px 24px rgba(0, 0, 0, .10);
}

.nav-inner {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

/* Logo 区域 */
.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  text-decoration: none;
}

.nav-logo img {
  height: 32px;
  width: auto;
}

.nav-logo-text {
  font-size: 1.1rem;
  font-weight: 700;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* 主导航链接 */
.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  font-size: .9rem;
  font-weight: 600;
  color: var(--text);
  letter-spacing: .02em;
  position: relative;
  transition: color var(--transition);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient);
  transition: width var(--transition);
}

.nav-link:hover { color: var(--cyan-dark); }
.nav-link:hover::after { width: 100%; }

/* 语言切换 */
.lang-switcher {
  display: flex;
  align-items: center;
  gap: 2px;
  border: 1.5px solid rgba(0, 217, 255, 0.35);
  border-radius: 20px;
  padding: 2px 6px;
  flex-shrink: 0;
}

.lang-btn {
  background: none;
  border: none;
  cursor: pointer;
  font-size: .82rem;
  font-weight: 600;
  color: var(--text-light);
  padding: 3px 8px;
  border-radius: 14px;
  transition: all var(--transition);
  font-family: var(--font);
}

.lang-btn:hover {
  color: var(--text);
}

.lang-btn.active {
  background: var(--gradient);
  color: var(--white);
}

.lang-sep {
  color: rgba(0, 217, 255, 0.4);
  font-size: .8rem;
  user-select: none;
}

/* 汉堡按钮（仅移动端显示） */
.nav-hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  border-radius: 6px;
  transition: background var(--transition);
}

.nav-hamburger:hover { background: rgba(0,217,255,.08); }

.nav-hamburger span {
  display: block;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: all var(--transition);
}

/* 汉堡激活状态动效 */
.nav-hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-hamburger.open span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}
.nav-hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* 移动端菜单抽屉 */
.nav-mobile {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.97);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  padding: 16px 24px 24px;
  border-bottom: 1px solid rgba(0, 217, 255, 0.15);
  box-shadow: 0 8px 24px rgba(0,0,0,.08);
  z-index: 999;
  flex-direction: column;
  gap: 4px;
  animation: slideDown .25s ease;
}

.nav-mobile.open {
  display: flex;
}

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-12px); }
  to   { opacity: 1; transform: translateY(0); }
}

.nav-mobile .nav-link {
  padding: 12px 4px;
  font-size: 1rem;
  border-bottom: 1px solid rgba(0,0,0,.04);
}

.nav-mobile .lang-switcher {
  margin-top: 12px;
  align-self: flex-start;
}

/* ════════════════════════════════════════════
   Hero 区块
════════════════════════════════════════════ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  position: relative;
  overflow: hidden;
  background: linear-gradient(145deg, #0a0a1a 0%, #0d0d2e 40%, #1a0a2e 100%);
  padding-top: var(--nav-height);
}

/* 动态粒子背景图层 */
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 20% 30%, rgba(0,217,255,.18) 0%, transparent 70%),
    radial-gradient(ellipse 50% 60% at 80% 70%, rgba(156,39,255,.18) 0%, transparent 70%);
  pointer-events: none;
}

/* 装饰光晕 */
.hero::after {
  content: '';
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0,217,255,.06) 0%, transparent 70%);
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 860px;
  padding: 40px 24px;
}

.hero-badge {
  display: inline-block;
  border: 1px solid rgba(0,217,255,.4);
  border-radius: 20px;
  padding: 4px 16px;
  font-size: .78rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--cyan);
  margin-bottom: 24px;
  animation: fadeInDown .7s ease both;
}

.hero-title {
  font-size: clamp(1.6rem, 4vw, 2.8rem);
  font-weight: 800;
  line-height: 1.25;
  color: var(--white);
  margin-bottom: 12px;
  animation: fadeInDown .7s .1s ease both;
}

.hero-subtitle {
  font-size: clamp(.9rem, 2vw, 1.1rem);
  color: rgba(255,255,255,.55);
  margin-bottom: 20px;
  animation: fadeInDown .7s .15s ease both;
}

.hero-slogan {
  font-size: clamp(1rem, 2.5vw, 1.3rem);
  color: rgba(255,255,255,.8);
  max-width: 600px;
  margin: 0 auto 36px;
  animation: fadeInDown .7s .2s ease both;
}

.hero-cta {
  display: inline-block;
  padding: 14px 36px;
  border-radius: 32px;
  background: var(--gradient);
  color: var(--white);
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: .04em;
  cursor: pointer;
  border: none;
  transition: transform .2s ease, box-shadow .2s ease;
  animation: fadeInDown .7s .3s ease both;
  box-shadow: 0 4px 24px rgba(0,217,255,.3);
  text-decoration: none;
}

.hero-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(0,217,255,.45);
}

/* 滚动提示箭头 */
.hero-scroll {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  color: rgba(255,255,255,.35);
  font-size: .72rem;
  letter-spacing: .08em;
  animation: bounce 2s infinite;
  cursor: pointer;
  z-index: 1;
}

.hero-scroll svg {
  width: 20px;
  height: 20px;
  display: inline;
}

@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50%       { transform: translateX(-50%) translateY(8px); }
}

@keyframes fadeInDown {
  from { opacity: 0; transform: translateY(-20px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ════════════════════════════════════════════
   通用 Section 布局
════════════════════════════════════════════ */
.section {
  padding: 96px 0;
}

.section-alt {
  background: var(--white);
}

.section-header {
  text-align: center;
  margin-bottom: 56px;
}

.section-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 800;
  color: var(--text);
  line-height: 1.25;
}

.section-desc {
  margin-top: 16px;
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
  color: var(--text-light);
  font-size: 1.05rem;
  line-height: 1.75;
}

/* ════════════════════════════════════════════
   About 区块
════════════════════════════════════════════ */
.about-intro {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 52px;
  color: var(--text-light);
  font-size: 1.05rem;
  line-height: 1.8;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
}

.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 36px 32px;
  box-shadow: var(--shadow-sm);
  border: 1px solid rgba(0,217,255,.1);
  transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(0,217,255,.3);
}

.card-icon {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  background: var(--gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  flex-shrink: 0;
}

.card-icon svg {
  width: 28px;
  height: 28px;
  fill: none;
  stroke: #fff;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  display: inline;
}

.card-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text);
}

.card-desc {
  font-size: .95rem;
  color: var(--text-light);
  line-height: 1.7;
}

/* ════════════════════════════════════════════
   Expertise 区块
════════════════════════════════════════════ */
.expertise-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 28px;
}

.expertise-item {
  background: var(--white);
  border-radius: var(--radius);
  padding: 32px 28px;
  box-shadow: var(--shadow-sm);
  border-left: 4px solid transparent;
  border-image: var(--gradient) 1;
  transition: box-shadow .3s ease, transform .3s ease;
}

.expertise-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}

.expertise-icon {
  font-size: 2.2rem;
  margin-bottom: 16px;
  line-height: 1;
}

.expertise-title {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text);
}

.expertise-desc {
  font-size: .92rem;
  color: var(--text-light);
  line-height: 1.7;
}

/* ════════════════════════════════════════════
   Contact 区块
════════════════════════════════════════════ */
.contact-box {
  max-width: 680px;
  margin: 0 auto;
  background: var(--white);
  border-radius: 20px;
  padding: 52px 48px;
  box-shadow: var(--shadow-md);
  border: 1px solid rgba(0,217,255,.12);
}

.contact-items {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.contact-item-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: linear-gradient(135deg, rgba(0,217,255,.12), rgba(156,39,255,.12));
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.contact-item-icon svg {
  width: 20px;
  height: 20px;
  fill: none;
  stroke: url(#navGrad);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  display: inline;
}

.contact-item-body {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.contact-label {
  font-size: .78rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--text-light);
}

.contact-value {
  font-size: 1rem;
  color: var(--text);
  word-break: break-word;
}

.contact-value a {
  color: var(--cyan-dark);
  transition: color var(--transition);
}
.contact-value a:hover { color: var(--purple); }

/* ════════════════════════════════════════════
   Footer
════════════════════════════════════════════ */
.site-footer {
  background: #0d0d1e;
  color: rgba(255,255,255,.55);
  padding: 36px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-copy {
  font-size: .82rem;
  line-height: 1.5;
}

.footer-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-link {
  font-size: .82rem;
  color: rgba(255,255,255,.45);
  transition: color var(--transition);
}

.footer-link:hover {
  color: var(--cyan);
}

/* ════════════════════════════════════════════
   Privacy 页专用样式
════════════════════════════════════════════ */
.privacy-header {
  background: linear-gradient(135deg, #00D9FF 0%, #9C27FF 100%);
  color: var(--white);
  padding: calc(var(--nav-height) + 48px) 24px 56px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.privacy-header::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 20% 30%, rgba(255,255,255,.12) 0%, transparent 60%),
    radial-gradient(ellipse 50% 60% at 80% 70%, rgba(0,0,0,.1) 0%, transparent 60%);
  pointer-events: none;
}

.privacy-header-content {
  position: relative;
  z-index: 1;
}

.privacy-header .badge {
  background: rgba(255,255,255,.2);
  -webkit-text-fill-color: #fff;
  color: #fff;
  border: 1px solid rgba(255,255,255,.4);
  border-radius: 16px;
  padding: 3px 12px;
  font-size: .75rem;
}

.privacy-header h1 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  margin-bottom: 10px;
}

.privacy-header p {
  font-size: 1.05rem;
  opacity: .8;
}

.privacy-effective {
  font-size: .85rem;
  opacity: .65;
  margin-top: 8px;
}

.privacy-body {
  max-width: 800px;
  margin: 0 auto;
  padding: 60px 24px 80px;
}

.privacy-section {
  margin-bottom: 40px;
}

.privacy-section h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 2px solid;
  border-image: var(--gradient) 1;
}

.privacy-section p {
  color: var(--text-light);
  line-height: 1.8;
  font-size: .98rem;
}

.privacy-contact-info {
  margin-top: 12px;
  padding: 16px 20px;
  background: linear-gradient(135deg, rgba(0,217,255,.06), rgba(156,39,255,.06));
  border-radius: 10px;
  border: 1px solid rgba(0,217,255,.15);
}

.privacy-contact-info p {
  margin-bottom: 4px;
}

.privacy-contact-info a {
  color: var(--cyan-dark);
  font-weight: 600;
}

.privacy-back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 40px;
  padding: 10px 24px;
  border-radius: 24px;
  border: 1.5px solid rgba(0,217,255,.35);
  color: var(--cyan-dark);
  font-weight: 600;
  font-size: .9rem;
  transition: all var(--transition);
}

.privacy-back:hover {
  background: var(--gradient);
  color: var(--white);
  border-color: transparent;
}

/* ════════════════════════════════════════════
   响应式 — 移动端（≤ 768px）
════════════════════════════════════════════ */
@media (max-width: 768px) {
  .nav-links {
    display: none;
  }

  .nav-hamburger {
    display: flex;
  }

  /* 桌面端语言切换隐藏（改在移动菜单中） */
  .nav-right > .lang-switcher {
    display: none;
  }

  .hero-title {
    font-size: 1.5rem;
  }

  .section {
    padding: 64px 0;
  }

  .contact-box {
    padding: 36px 24px;
  }

  .footer-inner {
    flex-direction: column;
    text-align: center;
  }

  .footer-links {
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .cards-grid,
  .expertise-grid {
    grid-template-columns: 1fr;
  }
}