/* ==========================================================================
   SaleOA — 产品落地页
   设计语言：Apple 式极简 · 黑白灰
   要点：大留白、细字重、超大标题、近白底 #fbfbfd、纯黑白 + 中性灰阶
   ========================================================================== */

:root {
  /* —— 背景层（Apple 页面经典三档）—— */
  --bg-page:      #ffffff;  /* 页面主背景 */
  --bg-alt:       #fbfbfd;  /* Apple 标志性近白 */
  --bg-card:      #ffffff;  /* 卡片 */
  --bg-sunken:    #f5f5f7;  /* 内嵌面板 / 输入底 */
  --bg-elev:      #fafafa;  /* 面板栏 */
  --bg-dark:      #1d1d1f;  /* 深色区块 */
  --bg-dark-2:    #2b2b2e;  /* 深色内嵌 */
  --bg-footer:    #f5f5f7;

  /* —— 描边（Apple 用极浅灰 + 组件用深色 hairline）—— */
  --line-hair:    #d2d2d7;  /* 组件 hairline */
  --line:         #e5e5ea;  /* 卡片描边 */
  --line-subtle:  #f0f0f2;  /* 分隔线 */
  --line-strong:  #c7c7cc;
  --line-dark:    #3a3a3c;  /* 深色区块 hairline */

  /* —— 中性灰阶（Apple 文字层级）—— */
  --text-1:       #1d1d1f;  /* 主文字 */
  --text-2:       #2c2c2e;
  --text-3:       #424245;  /* 次级正文 */
  --text-4:       #515154;
  --text-5:       #6e6e73;  /* 说明文字 */
  --text-6:       #86868b;  /* 弱化说明 */
  --text-7:       #a1a1a6;
  --text-8:       #b0b0b5;

  /* —— 深色区块上的文字 —— */
  --dk-text-1:    #f5f5f7;
  --dk-text-2:    #c7c7cc;
  --dk-text-3:    #8e8e93;

  /* —— 强调：Apple 黑按钮 —— */
  --ink:          #1d1d1f;
  --ink-hover:    #000000;
  --ink-soft:     #e8e8ed;

  /* —— 圆角（Apple 偏大圆角）—— */
  --r-sm:  8px;
  --r-md:  12px;
  --r-lg:  18px;
  --r-xl:  22px;
  --r-pill:980px;

  /* —— 布局 —— */
  --pad-x:   72px;
  --pad-y:   120px;
  --content: 1440px;
  --gap-grid:20px;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg-page);
  color: var(--text-1);
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'Helvetica Neue',
               'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  font-size: 17px;
  line-height: 1.5;
  letter-spacing: -0.01em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}
h1, h2, h3, h4 { margin: 0; font-weight: 600; letter-spacing: -0.02em; }
p { margin: 0; }
ul { margin: 0; padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
svg { display: block; }
button { font-family: inherit; }

.hero, .stats-bar, .problem, .how, .core,
.grid-section, .testimonials, .pricing, .faq,
.final-cta, .site-footer { width: 100%; }
.hero, .stats-bar, .problem, .how, .core,
.grid-section, .testimonials, .pricing, .faq,
.final-cta, .site-footer { max-width: var(--content); margin: 0 auto; }

/* ==========================================================================
   HEADER — Apple 毛玻璃导航
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, .72);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid transparent;
  transition: border-color .3s ease, background .3s ease;
}
.site-header.is-scrolled {
  border-bottom-color: var(--line-subtle);
  background: rgba(255, 255, 255, .86);
}
.header-inner {
  max-width: var(--content);
  margin: 0 auto;
  padding: 14px var(--pad-x);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 48px;
}
.brand { display: flex; align-items: center; gap: 9px; }
.brand-mark {
  width: 26px; height: 26px;
  display: grid; place-items: center;
  color: var(--ink);
}
.brand-mark svg { width: 20px; height: 20px; }
.brand-name {
  font-weight: 600; font-size: 20px;
  color: var(--text-1);
  letter-spacing: -0.02em;
}
.nav { display: flex; align-items: center; gap: 32px; }
.nav a {
  font-size: 14px; font-weight: 400;
  color: var(--text-4);
  transition: color .2s ease;
}
.nav a:hover { color: var(--text-1); }
.header-actions { display: flex; align-items: center; gap: 18px; }
.login {
  font-size: 14px; font-weight: 400;
  color: var(--text-1);
  transition: opacity .2s ease;
}
.login:hover { opacity: .6; }

/* ---------- 按钮：Apple 风格（胶囊 / 纯黑 / 白字）---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 400; font-size: 17px;
  letter-spacing: -0.01em;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  transition: background .25s ease, color .25s ease, border-color .25s ease, opacity .25s ease;
  white-space: nowrap;
  cursor: pointer;
}
.btn-primary { background: var(--ink); color: #fff; padding: 14px 30px; }
.btn-primary:hover { background: var(--ink-hover); }
.btn-primary.btn-sm { padding: 8px 18px; font-size: 14px; }
.btn-ghost {
  background: transparent; color: var(--text-1);
  border-color: var(--line-hair);
  padding: 14px 26px;
}
.btn-ghost:hover { background: var(--bg-sunken); border-color: var(--line-strong); }
.btn-ghost.btn-sm { padding: 8px 16px; font-size: 14px; }

/* ==========================================================================
   HERO
   ========================================================================== */
.hero {
  display: flex;
  align-items: center;
  gap: 72px;
  padding: 104px var(--pad-x) 120px;
  background: var(--bg-page);
}
.hero-copy {
  flex: 1;
  display: flex; flex-direction: column; gap: 26px;
  min-width: 0;
}
.badge {
  align-self: flex-start;
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 15px;
  border-radius: var(--r-pill);
  background: var(--bg-sunken);
  font-size: 13px; font-weight: 400; color: var(--text-5);
}
.badge-dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--ink);
}
.hero-title {
  font-size: 66px;
  font-weight: 600;
  line-height: 1.06;
  letter-spacing: -0.035em;
  color: var(--text-1);
}
.hero-sub {
  max-width: 545px;
  font-size: 19px;
  line-height: 1.55;
  letter-spacing: -0.012em;
  color: var(--text-5);
}
.hero-actions { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.trust-row {
  display: flex; align-items: center; gap: 14px;
  font-size: 13px; color: var(--text-6);
}
.dot-sep { color: var(--text-8); }

/* ---------- 账号矩阵控制台（Apple 窗口风）---------- */
.matrix-panel {
  width: 500px; flex-shrink: 0;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(0,0,0,.02), 0 18px 44px -18px rgba(0,0,0,.14);
}
.matrix-bar {
  display: flex; align-items: center; justify-content: space-between;
  gap: 10px; padding: 15px 18px;
  background: var(--bg-elev);
  border-bottom: 1px solid var(--line-subtle);
}
.bar-left { display: flex; align-items: center; gap: 8px; width: 52px; }
.wb { width: 11px; height: 11px; border-radius: 50%; }
.wb-r { background: #ff5f57; } .wb-y { background: #febc2e; } .wb-g { background: #28c840; }
.bar-title { font-size: 12px; font-weight: 500; color: var(--text-5); }
.live-pill {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 11px; border-radius: var(--r-pill);
  background: var(--bg-sunken);
  font-size: 11px; font-weight: 500; color: var(--text-4);
}
.live-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--ink); }

.matrix-cols {
  display: flex; align-items: center; padding: 11px 18px;
  background: var(--bg-elev);
  border-bottom: 1px solid var(--line-subtle);
  font-size: 11px; font-weight: 500; color: var(--text-7);
  letter-spacing: 0;
}
.matrix-row {
  display: flex; align-items: center; padding: 14px 18px;
  background: var(--bg-card);
  border-bottom: 1px solid var(--line-subtle);
}
.matrix-row.alt { background: #fcfcfd; }
.col-acc { width: 170px; }
.col-env { width: 110px; }
.col-on  { width: 60px; }
.col-st  { width: 70px; }
.c-acc { font-size: 13px; font-weight: 500; color: var(--text-1); }
.c-env { font-size: 12.5px; color: var(--text-4); }
.c-on  { font-size: 12px; font-weight: 600; color: var(--ink); letter-spacing: .04em; }
.c-st  { font-size: 12.5px; color: var(--text-5); }
.matrix-foot {
  display: flex; align-items: center; justify-content: space-between;
  padding: 15px 18px;
  background: var(--bg-elev);
  font-size: 11.5px; color: var(--text-6);
}
.c-live { color: var(--ink); font-weight: 500; }

/* ==========================================================================
   STATS BAR
   ========================================================================== */
.stats-bar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 56px var(--pad-x);
  background: var(--bg-page);
  border-top: 1px solid var(--line-subtle);
  border-bottom: 1px solid var(--line-subtle);
}
.stat { display: flex; flex-direction: column; align-items: center; gap: 8px; flex: 1; text-align: center; }
.stat-n {
  font-size: 42px; font-weight: 600;
  letter-spacing: -0.03em; color: var(--text-1);
}
.stat-l { font-size: 14px; color: var(--text-5); }

/* ==========================================================================
   通用区块 / 标题
   ========================================================================== */
.section-head {
  display: flex; flex-direction: column; align-items: center;
  gap: 16px; text-align: center;
}
.eyebrow {
  font-size: 13px; font-weight: 600;
  color: var(--text-6);
  letter-spacing: .01em;
}
.section-title {
  font-size: 48px; font-weight: 600; line-height: 1.1;
  letter-spacing: -0.03em; color: var(--text-1);
}
.section-sub {
  max-width: 660px;
  font-size: 19px; line-height: 1.5;
  letter-spacing: -0.012em;
  color: var(--text-5);
}

/* ==========================================================================
   PROBLEM / SOLUTION
   ========================================================================== */
.problem {
  display: flex; flex-direction: column; gap: 64px;
  padding: var(--pad-y) var(--pad-x);
  background: var(--bg-alt);
}
.compare-row { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.compare-card {
  display: flex; flex-direction: column; gap: 22px;
  padding: 40px;
  border-radius: var(--r-xl);
}
.compare-card.before {
  background: var(--bg-card);
  border: 1px solid var(--line);
}
.compare-card.after {
  background: var(--bg-dark);
  border: 1px solid var(--bg-dark);
}
.cc-head { display: flex; align-items: center; gap: 10px; }
.tag {
  display: inline-flex; padding: 5px 13px;
  border-radius: var(--r-pill);
  font-size: 12px; font-weight: 500;
}
.tag-before { background: var(--bg-sunken); color: var(--text-5); }
.tag-after  { background: rgba(255,255,255,.14); color: var(--dk-text-1); }
.cc-title { font-size: 24px; font-weight: 600; letter-spacing: -0.02em; color: var(--text-1); }
.compare-card.after .cc-title { color: var(--dk-text-1); }
.cc-list { display: flex; flex-direction: column; gap: 0; }
.cc-list li {
  display: flex; align-items: flex-start; gap: 12px;
  padding: 8px 0;
  font-size: 15px; line-height: 1.55; color: var(--text-5);
}
.compare-card.after .cc-list li { color: var(--dk-text-2); }
.li-dot {
  width: 5px; height: 5px; border-radius: 50%;
  background: var(--text-8); flex-shrink: 0;
  margin-top: 9px;
}
.li-dot.dark { background: var(--ink); }
.compare-card.after .li-dot.dark { background: var(--dk-text-1); }

/* ==========================================================================
   HOW IT WORKS
   ========================================================================== */
.how {
  display: flex; flex-direction: column; gap: 60px;
  padding: var(--pad-y) var(--pad-x);
  background: var(--bg-page);
}
.steps-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.step {
  display: flex; flex-direction: column; gap: 16px;
  padding: 34px;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
}
.step-num {
  font-size: 14px; font-weight: 600;
  color: var(--text-7);
  letter-spacing: .04em;
}
.step-title { font-size: 21px; font-weight: 600; letter-spacing: -0.02em; color: var(--text-1); }
.step-desc { font-size: 15px; line-height: 1.55; color: var(--text-5); }

/* ==========================================================================
   CORE FEATURES
   ========================================================================== */
.core {
  display: flex; flex-direction: column; gap: 96px;
  padding: var(--pad-y) var(--pad-x);
  background: var(--bg-alt);
}
.feature-row {
  display: grid; grid-template-columns: 1fr 460px;
  align-items: center; gap: 80px;
}
.feature-copy { display: flex; flex-direction: column; gap: 22px; min-width: 0; }
.f-num { font-size: 13px; font-weight: 600; color: var(--text-6); letter-spacing: .01em; }
.f-title {
  font-size: 40px; font-weight: 600; line-height: 1.14;
  letter-spacing: -0.03em; color: var(--text-1);
}
.f-desc { max-width: 500px; font-size: 17px; line-height: 1.6; letter-spacing: -0.01em; color: var(--text-5); }
.f-list { display: flex; flex-direction: column; gap: 14px; }
.f-list li {
  display: flex; align-items: center; gap: 12px;
  font-size: 15px; color: var(--text-3);
}
.chk {
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--ink);
  flex-shrink: 0;
  position: relative;
}
.chk::after {
  content: '';
  position: absolute; inset: 0;
  background: no-repeat center/11px url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none'%3E%3Cpath d='m4 12.5 5 5L20 6.5' stroke='%23ffffff' stroke-width='3.4' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
}

/* ---------- 功能可视化容器 ---------- */
.feature-visual {
  width: 460px;
  display: flex; flex-direction: column; gap: 14px;
  padding: 28px;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  box-shadow: 0 1px 3px rgba(0,0,0,.02), 0 14px 36px -20px rgba(0,0,0,.12);
}
.fv-head { display: flex; align-items: center; justify-content: space-between; }
.fv-title { font-size: 12px; font-weight: 500; color: var(--text-6); }
.pill {
  padding: 3px 10px; border-radius: var(--r-pill);
  background: var(--bg-sunken);
  font-size: 10.5px; font-weight: 500; color: var(--text-5);
}

/* 隔离网格 2×2 */
.iso-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.env {
  display: flex; flex-direction: column; gap: 7px;
  padding: 16px; height: 108px;
  background: var(--bg-sunken);
  border-radius: var(--r-md);
}
.env-id { font-size: 13px; font-weight: 600; color: var(--text-1); letter-spacing: .01em; }
.env-ip { font-size: 11px; color: var(--text-6); }
.env-cnt { font-size: 11px; font-weight: 500; color: var(--text-4); margin-top: auto; }

/* 聊天可视化 */
.chat-visual { height: 348px; }
.msg-left  { display: flex; }
.msg-right { display: flex; justify-content: flex-end; }
.bubble-in {
  width: 250px; padding: 12px 15px;
  border-radius: 16px; border-top-left-radius: 5px;
  background: var(--bg-sunken);
}
.bubble-in p { font-size: 13.5px; line-height: 1.5; color: var(--text-3); }
.msg-time { display: block; margin-top: 5px; font-size: 10px; color: var(--text-7); }
.msg-time.dark { color: var(--dk-text-3); margin-top: 0; }
.bubble-out {
  width: 292px; padding: 12px 15px;
  border-radius: 16px; border-top-right-radius: 5px;
  background: var(--ink);
  display: flex; flex-direction: column; gap: 8px;
}
.bubble-out p { font-size: 13.5px; line-height: 1.55; color: #f0f0f2; }
.msg-meta { display: flex; align-items: center; gap: 6px; }
.ai-badge {
  padding: 2px 7px; border-radius: var(--r-pill);
  background: rgba(255,255,255,.18);
  font-size: 9px; font-weight: 600; color: #fff;
  letter-spacing: .04em;
}
.chat-info {
  display: flex; gap: 20px;
  padding-top: 10px; margin-top: auto;
  font-size: 10.5px; color: var(--text-7);
}

/* 联系人提取 + 权限 */
.contact-row {
  display: flex; align-items: center; gap: 12px;
  padding: 12px 15px;
  border-radius: var(--r-sm);
  background: var(--bg-sunken);
}
.cr-num  { width: 130px; font-size: 12.5px; color: var(--text-3); }
.cr-name { flex: 1; font-size: 12.5px; color: var(--text-6); }
.cr-done { font-size: 11px; font-weight: 500; color: var(--text-4); }
.perm-box {
  display: flex; flex-direction: column; gap: 12px;
  padding: 16px; margin-top: 2px;
  background: var(--bg-elev);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
}
.perm-title { font-size: 12px; font-weight: 600; color: var(--text-4); }
.perm-row { display: flex; gap: 24px; flex-wrap: wrap; }
.toggle-group { display: inline-flex; align-items: center; gap: 8px; }
.toggle {
  width: 34px; height: 20px; border-radius: var(--r-pill);
  background: #d8d8de;
  display: flex; align-items: center;
  padding: 2px;
  transition: background .25s ease;
  flex-shrink: 0;
}
.toggle .knob {
  width: 16px; height: 16px; border-radius: 50%;
  background: #fff;
  box-shadow: 0 1px 2px rgba(0,0,0,.16);
  transform: translateX(0);
  transition: transform .25s ease;
}
.toggle.on { background: var(--ink); }
.toggle.on .knob { transform: translateX(14px); }
.toggle-label { font-size: 11.5px; color: var(--text-5); }

/* ==========================================================================
   FEATURE GRID
   ========================================================================== */
.grid-section {
  display: flex; flex-direction: column; gap: 56px;
  padding: var(--pad-y) var(--pad-x);
  background: var(--bg-page);
}
.cards-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--gap-grid); }
.card {
  display: flex; flex-direction: column; gap: 14px;
  padding: 30px;
  background: var(--bg-alt);
  border: 1px solid transparent;
  border-radius: var(--r-xl);
  transition: background .25s ease;
}
.card:hover { background: var(--bg-sunken); }
.card-icon {
  width: 40px; height: 40px;
  border-radius: 11px;
  background: var(--bg-sunken);
  display: grid; place-items: center;
  flex-shrink: 0;
  color: var(--ink);
}
.card:hover .card-icon { background: #e8e8ed; }
.card-icon svg { width: 21px; height: 21px; }
.card-title { font-size: 19px; font-weight: 600; letter-spacing: -0.02em; color: var(--text-1); }
.card-desc { font-size: 15px; line-height: 1.55; color: var(--text-5); }

/* ==========================================================================
   TESTIMONIALS
   ========================================================================== */
.testimonials {
  display: flex; flex-direction: column; gap: 56px;
  padding: var(--pad-y) var(--pad-x);
  background: var(--bg-alt);
}
.quote-card {
  margin: 0;
  display: flex; flex-direction: column; justify-content: space-between; gap: 24px;
  padding: 34px;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
}
.quote-card blockquote {
  margin: 0;
  font-size: 16px; line-height: 1.65; letter-spacing: -0.01em; color: var(--text-3);
}
.quote-card figcaption { display: flex; flex-direction: column; gap: 3px; }
.quote-card strong { font-size: 14px; font-weight: 600; color: var(--text-1); }
.quote-card figcaption span { font-size: 13px; color: var(--text-6); }

/* ==========================================================================
   PRICING
   ========================================================================== */
.pricing {
  display: flex; flex-direction: column; gap: 56px;
  padding: var(--pad-y) var(--pad-x);
  background: var(--bg-page);
}
.price-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; align-items: start; }
.plan {
  display: flex; flex-direction: column; gap: 26px;
  padding: 38px;
  background: var(--bg-alt);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
}
.plan-featured {
  background: var(--bg-dark);
  border: 1px solid var(--bg-dark);
}
.badge-row { display: flex; justify-content: flex-start; }
.featured-badge {
  padding: 5px 13px; border-radius: var(--r-pill);
  background: rgba(255,255,255,.16);
  font-size: 12px; font-weight: 500; color: var(--dk-text-1);
}
.plan-top { display: flex; flex-direction: column; gap: 10px; }
.plan-name { font-size: 20px; font-weight: 600; letter-spacing: -0.02em; color: var(--text-1); }
.plan-featured .plan-name { color: var(--dk-text-1); }
.plan-desc { font-size: 14px; color: var(--text-6); }
.plan-featured .plan-desc { color: var(--dk-text-3); }
.plan-price { display: flex; align-items: baseline; gap: 6px; }
.plan-price .cur { font-size: 22px; font-weight: 500; color: var(--text-1); }
.plan-price .num { font-size: 50px; font-weight: 600; line-height: 1; letter-spacing: -0.035em; color: var(--text-1); }
.plan-price .per { font-size: 15px; color: var(--text-6); }
.plan-featured .plan-price .cur,
.plan-featured .plan-price .num { color: var(--dk-text-1); }
.plan-featured .plan-price .per { color: var(--dk-text-3); }
.plan-btn {
  display: flex; align-items: center; justify-content: center;
  padding: 13px 0;
  border-radius: var(--r-pill);
  background: transparent;
  border: 1px solid var(--line-hair);
  font-size: 15px; font-weight: 400; color: var(--text-1);
  transition: background .25s ease, border-color .25s ease;
}
.plan-btn:hover { background: var(--bg-sunken); border-color: var(--line-strong); }
.plan-btn.primary { background: #fff; border-color: #fff; color: var(--text-1); font-weight: 500; }
.plan-btn.primary:hover { background: var(--dk-text-2); border-color: var(--dk-text-2); }
.plan-features { display: flex; flex-direction: column; gap: 15px; }
.plan-features li { display: flex; align-items: flex-start; gap: 11px; font-size: 14px; color: var(--text-4); }
.plan-features .li-dot { margin-top: 8px; }
.plan-featured .plan-features li { color: var(--dk-text-2); }
.plan-featured .plan-features .li-dot.dark { background: var(--dk-text-1); }

/* ==========================================================================
   FAQ
   ========================================================================== */
.faq {
  display: flex; flex-direction: column; gap: 56px;
  padding: var(--pad-y) var(--pad-x);
  background: var(--bg-alt);
}
.faq-list { display: flex; flex-direction: column; gap: 0; width: 100%; }
.faq-item {
  padding: 26px 0;
  background: transparent;
  border-bottom: 1px solid var(--line);
}
.faq-item:first-child { border-top: 1px solid var(--line); }
.faq-item summary {
  font-size: 18px; font-weight: 500; letter-spacing: -0.015em;
  color: var(--text-1);
  cursor: pointer; list-style: none;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: '';
  width: 13px; height: 13px; flex-shrink: 0;
  background: no-repeat center/13px url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none'%3E%3Cpath d='M6 9l6 6 6-6' stroke='%2386868b' stroke-width='2.4' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  transition: transform .25s ease;
}
.faq-item[open] summary::after { transform: rotate(180deg); }
.faq-item p {
  margin-top: 14px; max-width: 860px;
  font-size: 15.5px; line-height: 1.7; color: var(--text-5);
}

/* ==========================================================================
   FINAL CTA — Apple 深色收尾
   ========================================================================== */
.final-cta {
  display: flex; flex-direction: column; align-items: center;
  gap: 30px;
  padding: 130px var(--pad-x);
  background: var(--bg-dark);
  text-align: center;
}
.cta-title {
  font-size: 56px; font-weight: 600; line-height: 1.1;
  letter-spacing: -0.035em; color: var(--dk-text-1);
}
.cta-sub { max-width: 680px; font-size: 19px; line-height: 1.5; letter-spacing: -0.012em; color: var(--dk-text-3); }
.cta-actions { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; justify-content: center; margin-top: 4px; }
.cta-actions .btn-primary { background: #fff; color: var(--text-1); padding: 15px 32px; font-weight: 500; }
.cta-actions .btn-primary:hover { background: var(--dk-text-2); }
.cta-actions .btn-ghost { color: var(--dk-text-1); border-color: rgba(255,255,255,.28); padding: 15px 28px; }
.cta-actions .btn-ghost:hover { background: rgba(255,255,255,.08); border-color: rgba(255,255,255,.45); }

/* ==========================================================================
   FOOTER
   ========================================================================== */
.site-footer {
  display: flex; flex-direction: column; gap: 40px;
  padding: 64px var(--pad-x) 40px;
  background: var(--bg-footer);
}
.foot-top { display: flex; justify-content: space-between; gap: 40px; }
.foot-brand { width: 380px; flex-shrink: 0; display: flex; flex-direction: column; gap: 14px; }
.brand-row { display: flex; align-items: center; gap: 9px; }
.brand-row .brand-mark { width: 22px; height: 22px; }
.brand-row .brand-mark svg { width: 18px; height: 18px; }
.brand-row .brand-name { font-size: 18px; }
.foot-brand p { font-size: 14px; line-height: 1.7; color: var(--text-6); }
.foot-col { display: flex; flex-direction: column; gap: 14px; }
.foot-col h4 { font-size: 13px; font-weight: 600; color: var(--text-1); }
.foot-col a { font-size: 14px; color: var(--text-6); transition: color .2s ease; }
.foot-col a:hover { color: var(--text-1); }
.foot-divider { height: 1px; background: var(--line); }
.foot-bottom {
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px; flex-wrap: wrap;
  font-size: 13px; color: var(--text-6);
}

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width: 1280px) {
  :root { --pad-x: 48px; }
  .hero { gap: 48px; }
  .hero-title { font-size: 56px; }
  .cta-title { font-size: 46px; }
  .section-title { font-size: 40px; }
  .f-title { font-size: 34px; }
  .matrix-panel { width: 440px; }
  .feature-row { grid-template-columns: 1fr 420px; gap: 56px; }
  .feature-visual { width: 420px; }
  .col-acc { width: 150px; }
}

@media (max-width: 1024px) {
  :root { --pad-x: 32px; --pad-y: 88px; }
  .hero { flex-direction: column; align-items: stretch; gap: 48px; }
  .matrix-panel { width: 100%; }
  .hero-sub { max-width: none; }
  .feature-row { grid-template-columns: 1fr; gap: 40px; }
  .feature-visual { width: 100%; }
  .feature-row .chat-visual { order: 2; }
  .steps-row { grid-template-columns: repeat(2, 1fr); }
  .cards-row, .price-row, .compare-row { grid-template-columns: 1fr; }
  .foot-top { flex-wrap: wrap; }
  .foot-brand { width: 100%; }
}

@media (max-width: 720px) {
  :root { --pad-x: 20px; --pad-y: 68px; }
  body { font-size: 16px; }
  .nav { display: none; }
  .hero-title { font-size: 40px; }
  .section-title { font-size: 31px; }
  .section-sub { font-size: 17px; }
  .f-title { font-size: 28px; }
  .cta-title { font-size: 33px; }
  .cta-sub { font-size: 17px; }
  .stats-bar { flex-wrap: wrap; gap: 34px; }
  .stat { flex: 1 1 40%; }
  .stat-n { font-size: 32px; }
  .steps-row { grid-template-columns: 1fr; }
  .hero-actions, .cta-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .btn, .cta-actions .btn { width: 100%; }
  .foot-bottom { flex-direction: column; align-items: flex-start; gap: 12px; }
  .matrix-row { padding: 13px 14px; }
  .col-acc { width: 128px; }
  .col-env { width: 96px; }
  .c-acc, .c-env { font-size: 11.5px; }
  .compare-card { padding: 28px; }
  .plan { padding: 30px; }
}

/* ==========================================================================
   QR — 试用与咨询（微信扫码）
   ========================================================================== */
.qr-section {
  max-width: var(--content);
  margin: 0 auto;
  padding: var(--pad-y) var(--pad-x);
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 56px;
  background: var(--bg-alt);
}
.qr-panel {
  display: flex;
  align-items: center;
  gap: 48px;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  padding: 40px 56px;
  box-shadow: 0 1px 3px rgba(0,0,0,.02), 0 14px 36px -20px rgba(0,0,0,.12);
}
.qr-frame {
  padding: 12px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
}
.qr-frame img {
  display: block;
  width: 264px;
  height: 264px;
  border-radius: var(--r-md);
}
.qr-meta {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
  max-width: 280px;
}
.qr-app {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 18px; font-weight: 600; letter-spacing: -0.01em;
  color: var(--text-1);
}
.qr-app svg { width: 22px; height: 22px; color: var(--ink); }
.qr-hint { font-size: 14px; line-height: 1.6; color: var(--text-5); }

@media (max-width: 720px) {
  .qr-panel { flex-direction: column; padding: 28px; gap: 24px; text-align: center; }
  .qr-frame img { width: 220px; height: 220px; }
  .qr-meta { align-items: center; max-width: none; }
}

/* ==========================================================================
   DOWNLOAD PAGE (download.html)
   同一套 Apple 黑白灰语言：一张主下载卡 + 步骤 + 校验值 + FAQ
   ========================================================================== */
.dl-hero, .dl-section { width: 100%; max-width: var(--content); margin: 0 auto; }
.dl-hero {
  display: flex; flex-direction: column; align-items: center; gap: 44px;
  padding: 92px var(--pad-x) 0;
}
.dl-section {
  display: flex; flex-direction: column; align-items: center; gap: 52px;
  padding: var(--pad-y) var(--pad-x) 0;
}
.nav-current { color: var(--text-1); font-weight: 500; }

.dl-title {
  font-size: 54px; font-weight: 600; line-height: 1.08;
  letter-spacing: -0.03em; color: var(--text-1);
}
.dl-sub {
  max-width: 640px;
  font-size: 19px; line-height: 1.55; letter-spacing: -0.012em;
  color: var(--text-5);
}

/* ---------- 主下载卡 ---------- */
.dl-card {
  width: 100%; max-width: 880px;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  padding: 30px 34px;
  box-shadow: 0 1px 3px rgba(0,0,0,.02), 0 18px 44px -24px rgba(0,0,0,.16);
}
.dl-main { display: flex; align-items: center; gap: 20px; }
.dl-logo {
  width: 64px; height: 64px; flex-shrink: 0;
  padding: 8px; background: #fff;
  border: 1px solid var(--line); border-radius: 16px;
}
.dl-info { flex: 1 1 auto; min-width: 0; display: flex; flex-direction: column; gap: 8px; }
.dl-name { font-size: 22px; font-weight: 600; letter-spacing: -0.02em; color: var(--text-1); }
.dl-facts {
  display: flex; align-items: center; gap: 8px; flex-wrap: wrap;
  font-size: 14px; color: var(--text-5);
}
.dl-pill {
  display: inline-flex; align-items: center;
  padding: 3px 10px; border-radius: var(--r-pill);
  background: var(--bg-sunken); color: var(--text-3); font-size: 13px;
}
.dl-dot { color: var(--text-7); }
.dl-btn { flex-shrink: 0; padding: 15px 26px; }

.dl-req {
  margin-top: 26px; padding-top: 22px;
  border-top: 1px solid var(--line-subtle);
  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 44px;
}
.dl-req-item { display: flex; gap: 14px; font-size: 14px; }
.dl-req-k { width: 42px; flex-shrink: 0; color: var(--text-6); }
.dl-req-v { color: var(--text-3); }
.dl-note {
  margin-top: 22px;
  font-size: 14px; line-height: 1.75; color: var(--text-5);
}
.dl-note a {
  color: var(--text-1);
  text-decoration: underline; text-underline-offset: 3px;
}
.dl-note a:hover { opacity: .6; }

/* ---------- 步骤 ---------- */
.dl-steps {
  width: 100%;
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 22px;
}
.dl-step {
  display: flex; flex-direction: column; gap: 10px;
  padding: 26px 24px;
  background: var(--bg-alt);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
}
.dl-step-num {
  font-size: 13px; font-weight: 600; letter-spacing: .06em; color: var(--text-7);
}
.dl-step-title { font-size: 18px; font-weight: 600; color: var(--text-1); }
.dl-step-desc { font-size: 14px; line-height: 1.7; color: var(--text-5); }

/* ---------- 校验值 ---------- */
.dl-hash {
  width: 100%; max-width: 880px;
  padding: 22px 24px;
  background: var(--bg-sunken);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
}
.dl-hash-row { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }
.dl-hash-k { font-size: 13px; font-weight: 600; color: var(--text-6); flex-shrink: 0; }
.dl-hash-v {
  flex: 1 1 300px; min-width: 0;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, 'Liberation Mono', monospace;
  font-size: 13px; line-height: 1.6; color: var(--text-2);
  word-break: break-all;
}
.dl-copy {
  flex-shrink: 0;
  padding: 8px 16px; font-size: 13px;
  border-radius: var(--r-pill); border: 1px solid var(--line-hair);
  background: #fff; color: var(--text-1); cursor: pointer;
  transition: background .25s ease, border-color .25s ease;
}
.dl-copy:hover { background: var(--bg-sunken); border-color: var(--line-strong); }
.dl-copy.is-done { border-color: var(--line-strong); background: var(--bg-sunken); }
.dl-hash-hint { margin-top: 14px; font-size: 13px; line-height: 1.7; color: var(--text-6); }
.dl-inline-code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 12px; padding: 2px 6px;
  background: #fff; border: 1px solid var(--line); border-radius: 6px;
  color: var(--text-3);
}
.dl-faq { width: 100%; max-width: 880px; }

@media (max-width: 1080px) {
  .dl-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 720px) {
  .dl-hero { padding: 56px 22px 0; gap: 32px; }
  .dl-section { padding: 72px 22px 0; gap: 36px; }
  .dl-title { font-size: 36px; }
  .dl-card { padding: 24px 20px; }
  .dl-main { flex-direction: column; align-items: stretch; }
  .dl-info { align-items: center; text-align: center; }
  .dl-btn { width: 100%; }
  .dl-req { grid-template-columns: 1fr; }
  .dl-steps { grid-template-columns: 1fr; }
  .dl-hash { padding: 18px; }
  .dl-copy { width: 100%; }
}