/* ==========================================================================
   APKPure 下载单页 - 样式表
   简洁大气 · 绿色主题 · 自适应移动端
   ========================================================================== */

:root {
  --primary: #0B8F4F;
  --primary-dark: #077A42;
  --primary-light: #E8F6EE;
  --accent: #19C37D;
  --ink: #14281D;
  --ink-soft: #4A5D53;
  --muted: #7C8B83;
  --bg: #FFFFFF;
  --bg-alt: #F5FBF7;
  --line: #E6EEE9;
  --white: #FFFFFF;
  --shadow-sm: 0 2px 10px rgba(11, 143, 79, 0.06);
  --shadow-md: 0 12px 32px rgba(11, 143, 79, 0.12);
  --shadow-lg: 0 24px 60px rgba(11, 143, 79, 0.16);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --container: 1180px;
  --font: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 84px; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  font-size: 16px;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }

.container { max-width: var(--container); margin: 0 auto; padding: 0 24px; }
.container-narrow { max-width: 820px; }

/* ============================ 按钮 ============================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 600;
  border-radius: 999px;
  cursor: pointer;
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease, color .18s ease;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px) scale(.98); }

.btn-primary {
  background: var(--primary);
  color: var(--white);
  box-shadow: var(--shadow-md);
}
.btn-primary:hover { background: var(--primary-dark); box-shadow: var(--shadow-lg); transform: translateY(-2px); }

.btn-light {
  background: var(--white);
  color: var(--primary);
  box-shadow: 0 12px 30px rgba(0, 0, 0, .18);
}
.btn-light:hover { transform: translateY(-2px); box-shadow: 0 16px 36px rgba(0, 0, 0, .24); }

.btn-ghost {
  background: transparent;
  color: var(--ink-soft);
  border: 1.5px solid var(--line);
}
.btn-ghost:hover { border-color: var(--primary); color: var(--primary); }

.btn-lg { padding: 15px 34px; font-size: 17px; }
.btn-sm { padding: 9px 22px; font-size: 14px; }

.btn-icon { flex-shrink: 0; }

/* ============================ 顶部导航 ============================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .86);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; gap: 28px; height: 72px; }

.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 20px; }
.brand img { border-radius: 10px; }
.brand-name { letter-spacing: .3px; }

.main-nav { display: flex; align-items: center; gap: 28px; margin-left: auto; }
.nav-link { color: var(--ink-soft); font-size: 15px; font-weight: 500; transition: color .18s ease; position: relative; }
.nav-link:hover { color: var(--primary); }
.nav-link::after {
  content: ""; position: absolute; left: 0; bottom: -6px; width: 0; height: 2px;
  background: var(--primary); border-radius: 2px; transition: width .22s ease;
}
.nav-link:hover::after, .nav-link.active::after { width: 100%; }
.nav-link.active { color: var(--primary); }

.nav-cta { margin-left: 8px; }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px; height: 44px;
  background: var(--primary-light);
  border: none;
  border-radius: 10px;
  cursor: pointer;
  padding: 0 11px;
  margin-left: auto;
}
.nav-toggle span { height: 2px; background: var(--primary); border-radius: 2px; transition: transform .25s ease, opacity .25s ease; }
.nav-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================ Hero ============================ */
.hero { position: relative; background: linear-gradient(180deg, #F2FAF5 0%, #FFFFFF 100%); overflow: hidden; padding: 72px 0 120px; }
.hero-inner { display: grid; grid-template-columns: 1.05fr .95fr; gap: 56px; align-items: center; }

.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--white); color: var(--primary-dark);
  font-size: 13px; font-weight: 600;
  padding: 7px 16px; border-radius: 999px;
  box-shadow: var(--shadow-sm); margin-bottom: 22px;
}
.badge-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 3px rgba(25, 195, 125, .2); }

.hero-title { font-size: 54px; line-height: 1.15; font-weight: 800; letter-spacing: -.5px; }
.hero-title .accent { color: var(--primary); }

.hero-subtitle { margin-top: 20px; font-size: 18px; color: var(--ink-soft); max-width: 520px; }

.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 32px; }

.hero-stats { display: flex; gap: 40px; margin-top: 44px; }
.stat { display: flex; flex-direction: column; }
.stat strong { font-size: 28px; font-weight: 800; color: var(--primary); line-height: 1.2; }
.stat span { font-size: 13px; color: var(--muted); margin-top: 2px; }

.hero-visual { position: relative; display: flex; align-items: center; justify-content: center; }
.phone-frame {
  position: relative;
  width: min(420px, 88%);
  aspect-ratio: 1;
  border-radius: 44px;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  background: #fff;
}
.phone-frame img { width: 100%; height: 100%; object-fit: cover; }

.qr-card {
  position: absolute;
  right: 0; bottom: 6%;
  background: var(--white);
  border-radius: 18px;
  padding: 14px;
  box-shadow: var(--shadow-md);
  display: flex; flex-direction: column; align-items: center; gap: 8px;
  animation: float 5s ease-in-out infinite;
}
.qr-card img { width: 92px; height: 92px; border-radius: 6px; }
.qr-card span { font-size: 12px; color: var(--ink-soft); font-weight: 600; }

@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-12px); } }

.hero-wave {
  position: absolute; left: 0; right: 0; bottom: -2px; height: 80px;
  background: var(--bg);
  clip-path: ellipse(75% 100% at 50% 100%);
}

/* ============================ 通用 Section ============================ */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }

.section-head { text-align: center; max-width: 680px; margin: 0 auto 56px; }
.section-tag {
  display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: 2.5px;
  color: var(--primary); text-transform: uppercase; margin-bottom: 14px;
}
.section-tag-light { color: var(--accent); }
.section-title { font-size: 38px; font-weight: 800; line-height: 1.25; }
.section-lead { margin-top: 14px; font-size: 17px; color: var(--ink-soft); }

/* ============================ 基础介绍 ============================ */
.intro-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.intro-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 30px 26px;
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}
.intro-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); border-color: transparent; }
.intro-icon {
  width: 56px; height: 56px; border-radius: 16px;
  background: var(--primary-light); color: var(--primary);
  display: flex; align-items: center; justify-content: center; margin-bottom: 20px;
}
.intro-card h3 { font-size: 19px; font-weight: 700; margin-bottom: 10px; }
.intro-card p { font-size: 14.5px; color: var(--ink-soft); }

/* ============================ 功能介绍 ============================ */
.features-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.feature-card {
  background: var(--white);
  border-radius: var(--radius-md);
  padding: 34px 32px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--line);
  position: relative;
  transition: transform .22s ease, box-shadow .22s ease;
}
.feature-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-md); }
.feature-card-wide { grid-column: 1 / -1; }
.feature-num {
  font-size: 15px; font-weight: 800; color: var(--accent); letter-spacing: 1px;
  margin-bottom: 14px; font-family: "Helvetica Neue", Arial, sans-serif;
}
.feature-card h3 { font-size: 21px; font-weight: 700; margin-bottom: 12px; }
.feature-card p { font-size: 15.5px; color: var(--ink-soft); }

/* ============================ 安装使用 ============================ */
.guide-steps { display: flex; flex-direction: column; gap: 40px; }
.guide-step {
  display: grid; grid-template-columns: 320px 1fr; gap: 44px; align-items: center;
}
.guide-step:nth-child(even) { direction: rtl; }
.guide-step:nth-child(even) .guide-body,
.guide-step:nth-child(even) .guide-media { direction: ltr; }

.guide-media {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  aspect-ratio: 2 / 3;
  background: var(--bg-alt);
}
.guide-media img { width: 100%; height: 100%; object-fit: cover; }

.step-label { font-size: 13px; font-weight: 800; letter-spacing: 2px; color: var(--accent); }
.guide-body h3 { font-size: 26px; font-weight: 800; margin: 10px 0 14px; }
.guide-body p { font-size: 16px; color: var(--ink-soft); }

.guide-body-full {
  background: var(--primary-light);
  border-radius: var(--radius-lg);
  padding: 40px 44px;
  border: 1px solid rgba(11, 143, 79, .14);
}
.guide-tips { margin-top: 22px; display: flex; flex-wrap: wrap; gap: 12px 24px; }
.guide-tips li { font-size: 15px; font-weight: 600; color: var(--primary-dark); }

/* ============================ 下载板块 ============================ */
.download-section { background: linear-gradient(135deg, #0B8F4F 0%, #087A43 55%, #065F34 100%); padding: 96px 0; }
.download-panel {
  display: grid; grid-template-columns: 1fr auto; gap: 56px; align-items: center;
  max-width: 960px; margin: 0 auto;
}
.download-title { color: var(--white); font-size: 40px; font-weight: 800; line-height: 1.2; }
.download-sub { color: rgba(255, 255, 255, .82); font-size: 17px; margin-top: 12px; }

.download-meta {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px 32px;
  margin: 28px 0 32px; max-width: 420px;
}
.download-meta li { display: flex; flex-direction: column; }
.download-meta strong { color: rgba(255, 255, 255, .62); font-size: 13px; font-weight: 500; }
.download-meta span { color: var(--white); font-size: 16px; font-weight: 600; margin-top: 2px; }

.download-note { color: rgba(255, 255, 255, .6); font-size: 13px; margin-top: 16px; }

.download-qr { text-align: center; }
.qr-box {
  background: var(--white); padding: 18px; border-radius: 22px;
  box-shadow: 0 24px 50px rgba(0, 0, 0, .28); display: inline-block;
}
.qr-box img { width: 220px; height: 220px; border-radius: 8px; }
.qr-caption { color: var(--white); font-size: 15px; font-weight: 600; margin-top: 16px; }

/* ============================ FAQ ============================ */
.faq-list { display: flex; flex-direction: column; gap: 14px; }
.faq-item {
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius-md);
  overflow: hidden; transition: border-color .2s ease, box-shadow .2s ease;
}
.faq-item[open] { border-color: rgba(11, 143, 79, .3); box-shadow: var(--shadow-sm); }
.faq-item summary {
  list-style: none; cursor: pointer; padding: 20px 24px;
  font-weight: 700; font-size: 16.5px; color: var(--ink);
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+"; font-size: 22px; font-weight: 600; color: var(--primary);
  transition: transform .22s ease; flex-shrink: 0; line-height: 1;
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { padding: 0 24px 22px; color: var(--ink-soft); font-size: 15px; }

/* ============================ Footer ============================ */
.site-footer { background: #0F2B1D; color: rgba(255, 255, 255, .7); padding: 52px 0 36px; }
.footer-inner { display: flex; flex-direction: column; align-items: center; gap: 14px; text-align: center; }
.footer-brand { display: flex; align-items: center; gap: 10px; font-size: 20px; font-weight: 700; color: var(--white); }
.footer-brand img { border-radius: 8px; }
.footer-text { font-size: 13.5px; max-width: 640px; }
.footer-copy { font-size: 13px; color: rgba(255, 255, 255, .45); }

/* ============================ 入场动画 ============================ */
.intro-card, .feature-card, .guide-step, .faq-item {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .6s ease, transform .6s ease;
}
.intro-card.is-visible, .feature-card.is-visible, .guide-step.is-visible, .faq-item.is-visible {
  opacity: 1;
  transform: translateY(0);
}
.intro-card:nth-child(2), .feature-card:nth-child(2) { transition-delay: .06s; }
.intro-card:nth-child(3), .feature-card:nth-child(3) { transition-delay: .12s; }
.intro-card:nth-child(4), .feature-card:nth-child(4) { transition-delay: .18s; }

/* 尊重减少动画偏好 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation: none !important; transition: none !important; }
  .intro-card, .feature-card, .guide-step, .faq-item { opacity: 1; transform: none; }
}

/* ============================ 响应式 ============================ */
@media (max-width: 1024px) {
  .intro-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-title { font-size: 44px; }
}

@media (max-width: 860px) {
  .hero { padding: 48px 0 90px; }
  .hero-inner { grid-template-columns: 1fr; gap: 48px; text-align: center; }
  .hero-subtitle { margin-left: auto; margin-right: auto; }
  .hero-actions { justify-content: center; }
  .hero-stats { justify-content: center; }
  .hero-visual { order: 2; }
  .hero-text { order: 1; }

  .guide-step { grid-template-columns: 1fr; gap: 26px; }
  .guide-step:nth-child(even) { direction: ltr; }
  .guide-media { max-width: 320px; }

  .download-panel { grid-template-columns: 1fr; text-align: center; gap: 40px; }
  .download-meta { margin-left: auto; margin-right: auto; text-align: left; }
  .download-note { text-align: center; }

  /* 移动端导航 */
  .main-nav {
    position: fixed; inset: 72px 0 auto 0;
    flex-direction: column; gap: 0;
    background: var(--white);
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow-md);
    padding: 8px 24px 20px;
    transform: translateY(-120%);
    transition: transform .28s ease;
    margin-left: 0;
  }
  .main-nav.open { transform: translateY(0); }
  .main-nav .nav-link { padding: 14px 0; font-size: 16px; border-bottom: 1px solid var(--line); width: 100%; }
  .nav-cta { display: none; }
  .nav-toggle { display: flex; }
}

@media (max-width: 560px) {
  .section { padding: 68px 0; }
  .section-title { font-size: 30px; }
  .hero-title { font-size: 36px; }
  .hero-subtitle { font-size: 16px; }
  .hero-stats { gap: 24px; }
  .stat strong { font-size: 22px; }

  .intro-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr; }
  .feature-card-wide { grid-column: auto; }

  .qr-card { bottom: 2%; right: 2%; padding: 10px; }
  .qr-card img { width: 68px; height: 68px; }
  .qr-box img { width: 180px; height: 180px; }

  .download-title { font-size: 30px; }
  .btn-lg { width: 100%; }
  .guide-body-full { padding: 28px 22px; }
}