/* ============================================
   有招帮助中心 V2 — 清新蓝绿活力主题
   ============================================ */

/* --- CSS Variables --- */
:root {
  --primary: #00B4DB;
  --primary-dark: #0083B0;
  --primary-light: #E0F7FA;
  --primary-gradient: linear-gradient(135deg, #00B4DB 0%, #0083B0 100%);
  --accent: #FF8C42;
  --accent-light: #FFF3E0;
  --bg: #F5F9FC;
  --bg-white: #FFFFFF;
  --text-primary: #1A2B3C;
  --text-secondary: #5A6B7C;
  --text-light: #8FA3B8;
  --border: #E2ECF3;
  --shadow-sm: 0 2px 12px rgba(0, 180, 219, 0.08);
  --shadow-md: 0 4px 24px rgba(0, 180, 219, 0.12);
  --shadow-lg: 0 8px 40px rgba(0, 180, 219, 0.16);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 50px;
  --font: -apple-system, BlinkMacSystemFont, "PingFang SC", "Noto Sans SC", "Helvetica Neue", sans-serif;
  --nav-height: 64px;
  --transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.8;
  font-size: 18px; /* 中老年友好：基础字号加大 */
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-dark); }
img { max-width: 100%; height: auto; }
ul { list-style: none; }

/* --- Utility --- */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

.section { padding: 80px 0; }
.section-title {
  font-size: clamp(28px, 6vw, 42px); /* 原来24/5/36 */
  font-weight: 700;
  text-align: center;
  margin-bottom: 14px; /* 原来12 */
  color: var(--text-primary);
}
.section-subtitle {
  font-size: 18px; /* 原来16 */
  color: var(--text-light);
  text-align: center;
  margin-bottom: 52px; /* 原来48 */
  max-width: 560px; /* 原来520 */
  margin-left: auto;
  margin-right: auto;
}

/* ============================================
   NAVIGATION
   ============================================ */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-height);
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid transparent;
  z-index: 1000;
  transition: var(--transition);
}
.navbar.scrolled {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-sm);
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  font-size: 24px; /* 原来20，加大 */
  font-weight: 800;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.5px;
  white-space: nowrap;
}
/* guide.html / health-check.html 用的 .nav-brand 也要一样 */
.nav-brand {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 24px;
  font-weight: 800;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.5px;
  text-decoration: none;
  white-space: nowrap;
}
.nav-links {
  display: flex;
  gap: 8px;
}
.nav-link {
  padding: 10px 18px;
  border-radius: var(--radius-full);
  font-size: 16px; /* 原来14，加大 */
  font-weight: 600; /* 原来是500，加粗 */
  color: var(--text-secondary);
  transition: var(--transition);
}
.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  background: var(--primary-light);
}

/* Mobile menu button */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  flex-direction: column;
  gap: 5px;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition);
}

/* ============================================
   NAVBAR DARK (健康自检深色页面)
   ============================================ */
.navbar-dark {
  background: rgba(26,58,42,0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.navbar-dark.scrolled {
  border-bottom-color: rgba(255,255,255,0.15);
  box-shadow: 0 2px 12px rgba(0,0,0,0.30);
}
.navbar-dark .nav-brand {
  color: #fff;
  -webkit-text-fill-color: #fff;
  background: none;
  -webkit-background-clip: unset;
  background-clip: unset;
}
.navbar-dark .nav-link {
  color: rgba(255,255,255,0.70);
}
.navbar-dark .nav-link:hover,
.navbar-dark .nav-link.active {
  color: #d4a853;
  background: rgba(212,168,83,0.20);
}
.navbar-dark .nav-toggle span {
  background: rgba(255,255,255,0.80);
}
@media (max-width: 768px) {
  .navbar-dark .nav-links {
    background: rgba(26,58,42,0.98);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(255,255,255,0.10);
  }
}

/* ============================================
   HERO SECTION (首页)
   ============================================ */
.hero {
  min-height: 85vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: calc(var(--nav-height) + 40px) 20px 60px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%; left: -50%;
  width: 200%; height: 200%;
  background: radial-gradient(circle at 30% 40%, rgba(0,180,219,0.08) 0%, transparent 60%),
              radial-gradient(circle at 70% 60%, rgba(0,131,176,0.06) 0%, transparent 55%);
  animation: heroFloat 15s ease-in-out infinite alternate;
}
@keyframes heroFloat {
  0% { transform: translate(0, 0) rotate(0deg); }
  100% { transform: translate(-3%, 2%) rotate(1deg); }
}
.hero-content { position: relative; z-index: 1; }
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 22px; /* 原来是6px 18px */
  background: var(--primary-light);
  color: var(--primary-dark);
  border-radius: var(--radius-full);
  font-size: 15px; /* 原来13 */
  font-weight: 600;
  margin-bottom: 28px;
  animation: fadeInUp 0.6s ease both;
}
.hero-badge::before {
  content: '✦';
  font-size: 11px;
}
.hero-title {
  font-size: clamp(36px, 8vw, 64px); /* 原来32/7/56，加大 */
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 24px; /* 原来20 */
  letter-spacing: -1px;
  animation: fadeInUp 0.6s 0.1s ease both;
}
.hero-title .highlight {
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-desc {
  font-size: clamp(18px, 3vw, 22px); /* 原来16/2.5/19 */
  color: var(--text-secondary);
  max-width: 560px; /* 原来500，加宽 */
  margin: 0 auto 16px; /* 原来36，改成16 */
  animation: fadeInUp 0.6s 0.2s ease both;
  line-height: 1.6;
}
.hero-desc .desc-highlight {
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 700;
}
.hero-stats {
  font-size: clamp(15px, 2.5vw, 18px);
  color: var(--primary-dark);
  font-weight: 600;
  margin: 0 auto 20px;
  animation: fadeInUp 0.6s 0.3s ease both;
  line-height: 1.8;
}
.hero-tagline {
  font-size: clamp(17px, 2.6vw, 21px);
  color: var(--text-secondary);
  margin: 0 auto 32px;
  animation: fadeInUp 0.6s 0.35s ease both;
  letter-spacing: 1px;
}
.hero-tagline .tagline-big {
  display: inline-block;
  font-size: 1.35em;
  font-weight: 800;
  color: var(--primary);
  vertical-align: -3px;
  text-shadow: 0 1px 0 rgba(0,180,219,0.15);
  animation: taglineBigBounce 2.5s ease-in-out infinite;
}
.hero-tagline .tagline-small {
  display: inline-block;
  font-size: 0.85em;
  font-weight: 600;
  color: var(--accent);
  vertical-align: 0px;
  animation: taglineSmallBounce 2.5s ease-in-out infinite 0.15s;
}
@keyframes taglineBigBounce {
  0%, 100% { transform: scale(1) translateY(0); }
  50% { transform: scale(1.08) translateY(-2px); }
}
@keyframes taglineSmallBounce {
  0%, 100% { transform: scale(1) translateY(0); }
  50% { transform: scale(1.08) translateY(-1px); }
}
.hero-actions {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 0.6s 0.4s ease both;
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ============================================
   BUTTONS
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 16px 34px; /* 原来13/28，加大 */
  border-radius: var(--radius-full);
  font-size: 17px; /* 原来15 */
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  font-family: var(--font);
}
.btn-primary {
  background: var(--primary-gradient);
  color: #fff;
  box-shadow: 0 4px 16px rgba(0,180,219,0.3);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(0,180,219,0.4);
  color: #fff;
}
.btn-outline {
  background: var(--bg-white);
  color: var(--primary);
  border: 2px solid var(--border);
}
.btn-outline:hover {
  border-color: var(--primary);
  background: var(--primary-light);
  color: var(--primary-dark);
  transform: translateY(-2px);
}
.btn-accent {
  background: linear-gradient(135deg, #FF8C42 0%, #FF6B35 100%);
  color: #fff;
  box-shadow: 0 4px 16px rgba(255,140,66,0.3);
}
.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(255,140,66,0.4);
  color: #fff;
}
.btn-sm {
  padding: 9px 20px;
  font-size: 13px;
}

/* Ripple effect */
.btn::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle, rgba(255,255,255,0.35) 10%, transparent 10%);
  transform: scale(10);
  opacity: 0;
  transition: transform 0.5s, opacity 0.5s;
}
.btn:active::after {
  transform: scale(0);
  opacity: 1;
  transition: 0s;
}

/* ============================================
   CARD GRID (通用卡片)
   ============================================ */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}
.card {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  padding: 38px 30px; /* 原来32/28 */
  border: 1px solid var(--border);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}
.card-icon {
  width: 64px; /* 原来56 */
  height: 64px; /* 原来56 */
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 30px; /* 原来26 */
  margin-bottom: 22px; /* 原来20 */
  background: var(--primary-light);
  flex-shrink: 0;
}
.card-icon.orange { background: var(--accent-light); }
.card-icon.green { background: #E8F5E9; }
.card-icon.purple { background: #F3E5F5; }
.card h3 {
  font-size: 22px; /* 原来19 */
  font-weight: 700;
  margin-bottom: 12px; /* 原来10 */
  color: var(--text-primary);
}
.card p {
  font-size: 16px; /* 原来14 */
  color: var(--text-secondary);
  line-height: 1.8; /* 原来1.7 */
}
.card-arrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 20px; /* 原来18 */
  font-size: 16px; /* 原来14 */
  font-weight: 600;
  color: var(--primary);
}
.card-arrow::after {
  content: '→';
  transition: transform 0.3s;
}
.card:hover .card-arrow::after {
  transform: translateX(4px);
}

/* Feature card with number badge */
.feature-card {
  padding: 36px 28px;
}
.feature-card .feature-num {
  position: absolute;
  top: 20px;
  right: 24px;
  font-size: 48px;
  font-weight: 900;
  color: var(--border);
  line-height: 1;
}

/* ============================================ 
   PAGE HEADER (内页通用) 
   ============================================ */
.page-header {
  padding: calc(var(--nav-height) + 50px) 20px 50px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.page-header::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--primary-gradient);
  opacity: 0.04;
}
.page-header h1 {
  font-size: clamp(26px, 5vw, 40px);
  font-weight: 800;
  margin-bottom: 12px;
  position: relative;
}
.page-header p {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 500px;
  margin: 0 auto;
  position: relative;
}

/* ============================================
   FAQ 手风琴
   ============================================ */
.faq-category {
  margin-bottom: 40px;
}
.faq-category-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--primary-dark);
  margin-bottom: 16px;
  padding-left: 12px;
  border-left: 3px solid var(--primary);
}
.faq-item {
  background: var(--bg-white);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  margin-bottom: 10px;
  overflow: hidden;
  transition: var(--transition);
}
.faq-item:hover { border-color: var(--primary); }
.faq-question {
  width: 100%;
  padding: 18px 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  font-family: var(--font);
  text-align: left;
  transition: var(--transition);
}
.faq-question:hover { color: var(--primary); }
.faq-icon {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  flex-shrink: 0;
  transition: var(--transition);
}
.faq-item.active .faq-icon {
  background: var(--primary);
  color: #fff;
  transform: rotate(45deg);
}
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.3s ease;
}
.faq-answer-inner {
  padding: 0 22px 18px;
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
}
.faq-item.active .faq-answer {
  max-height: 300px;
}

/* ============================================
   CASE CARDS (案例)
   ============================================ */
.case-card {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  padding: 32px;
  border: 1px solid var(--border);
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}
.case-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}
.case-avatar {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: var(--primary-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 18px;
  flex-shrink: 0;
}
.case-name {
  font-size: 19px;
  font-weight: 700;
  margin-bottom: 4px;
}
.case-team {
  font-size: 13px;
  color: var(--text-light);
  margin-bottom: 16px;
}
.case-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 18px;
}
.stat-item {
  text-align: center;
  padding: 12px 8px;
  border-radius: var(--radius-sm);
  background: var(--bg);
}
.stat-num {
  font-size: 52px; /* 原来36，大幅加大！中老年用户必须大 */
  font-weight: 900; /* 原来800 */
  color: var(--primary);
  display: inline-block;
  line-height: 1.1;
}

/* 超大号文字（用于"零操作门槛"） */
.stat-num-big {
  font-size: 56px;
  font-weight: 900;
  color: var(--accent);
  display: inline-block;
}

/* 统计标签 - 加大加粗 */
.stat-label {
  font-size: 19px !important; /* 原来14！大幅加大 */
  font-weight: 700 !important;
  color: var(--text-primary) !important;
  margin-top: 8px;
  display: block;
}

/* 统计描述文字 */
.stat-desc {
  font-size: 15px; /* 新增 */
  color: var(--text-secondary);
  margin-top: 8px;
  line-height: 1.7;
}

/* 实时数据指示灯 */
.live-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #4CAF50;
  margin-left: 6px;
  vertical-align: middle;
  animation: livePulse 2s ease-in-out infinite;
  box-shadow: 0 0 6px rgba(76,175,80,0.5);
  position: relative;
  top: -2px;
}

/* Hero 实时跳动数字 */
.live-stat {
  display: inline-block;
  font-weight: 700;
  color: var(--primary-dark);
  transition: transform 0.2s ease, color 0.2s ease;
}
.live-stat.tick {
  transform: scale(1.18);
  color: var(--primary);
}
@keyframes livePulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.3); }
}
.stat-label {
  font-size: 11px;
  color: var(--text-light);
  margin-top: 2px;
}
.case-quote {
  font-size: 14px;
  color: var(--text-secondary);
  font-style: italic;
  border-left: 3px solid var(--accent);
  padding-left: 14px;
  margin-top: auto;
  line-height: 1.7;
}

/* ============================================
   CONTACT 页面
   ============================================ */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}
.contact-card {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  padding: 36px;
  border: 1px solid var(--border);
  text-align: center;
  transition: var(--transition);
}
.contact-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.contact-icon {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-md);
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  margin: 0 auto 18px;
}
.contact-card h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 8px;
}
.contact-card p {
  font-size: 14px;
  color: var(--text-secondary);
}
.qr-placeholder {
  width: 160px;
  height: 160px;
  border-radius: var(--radius-md);
  background: var(--bg);
  border: 2px dashed var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 18px auto 0;
  font-size: 13px;
  color: var(--text-light);
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  background: var(--text-primary);
  color: rgba(255,255,255,0.65);
  padding: 48px 20px 32px;
  margin-top: 60px;
}
.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}
.footer-brand {
  font-size: 18px;
  font-weight: 800;
  color: #fff;
}
.footer-brand span {
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.footer-links {
  display: flex;
  gap: 24px;
}
.footer-links a {
  color: rgba(255,255,255,0.55);
  font-size: 13px;
  transition: var(--transition);
}
.footer-links a:hover { color: #fff; }
.footer-copy {
  width: 100%;
  text-align: center;
  font-size: 12px;
  color: rgba(255,255,255,0.35);
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid rgba(255,255,255,0.08);
}

/* ============================================
   ANIMATIONS (Scroll reveal)
   ============================================ */
/* 默认可见：即使 JS 失败或 Observer 不触发，内容仍然显示 */
.reveal { opacity: 1; transform: translateY(0); }
/* JS 初始化后给需要动画的元素加此类（隐藏→滚动时显示） */
.reveal.reveal-wait {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.reveal-in { opacity: 1; transform: translateY(0); }
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }

/* ============================================
   RESPONSIVE
   ============================================ */

/* Tablet */
@media (max-width: 768px) {
  .nav-toggle { display: flex; }
  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: 0; right: 0;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(16px);
    flex-direction: column;
    padding: 20px;
    gap: 4px;
    border-bottom: 1px solid var(--border);
    transform: translateY(-120%);
    opacity: 0;
    transition: all 0.35s ease;
    z-index: 999;
  }
  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
  }
  .nav-link {
    padding: 14px 18px; /* 原来12/16 */
    font-size: 17px; /* 原来15 */
    border-radius: var(--radius-sm);
  }

  .hero { min-height: 75vh; padding-top: calc(var(--nav-height) + 30px); }
  .section { padding: 56px 0; }
  .card-grid { grid-template-columns: 1fr; gap: 16px; }
  .card { padding: 30px 24px; } /* 原来26/22 */

  .contact-grid { grid-template-columns: 1fr; }
  .case-stats { grid-template-columns: repeat(3, 1fr); gap: 8px; }
  .footer-inner { flex-direction: column; text-align: center; }
  .footer-links { flex-wrap: wrap; justify-content: center; }

  .faq-question { padding: 16px 18px; font-size: 15px; }
  .faq-answer-inner { padding: 0 18px 16px; }

  /* 移动端统计数字也要大 */
  .stat-num { font-size: 44px; }
  .stat-num-big { font-size: 48px; }
  .stat-label { font-size: 17px !important; }
}

/* Mobile small */
@media (max-width: 400px) {
  .hero-title { font-size: 32px; } /* 原来28 */
  .btn { padding: 14px 26px; font-size: 16px; } /* 原来11/22/14 */
  .card { padding: 26px 20px; } /* 原来22/18 */
  .case-stats { grid-template-columns: 1fr; }
  .stat-num { font-size: 38px; } /* 原来26 */
  .stat-label { font-size: 16px !important; }
}

/* Desktop large */
@media (min-width: 1024px) {
  .card-grid { grid-template-columns: repeat(4, 1fr); }
}