/* ==========================================================================
   SimpleWall 官方网站 - 全站样式
   配色基于产品 Logo（火焰）：焰橙 #F06000 / 深红 #E03000 / 焰黄 #F5A800
   风格：扁平、现代、专业 | HTML5 + CSS3 响应式
   ========================================================================== */

/* ---------- 1. 变量与基础 ---------- */
:root {
  --c-primary: #F06000;
  --c-primary-hover: #D85500;
  --c-primary-active: #BF4A00;
  --c-primary-soft: #FDF0E5;
  --c-primary-softer: #FBF7F2;
  --c-flame-red: #E03000;
  --c-amber: #F5A800;
  --c-ink: #1D2129;
  --c-ink-2: #2E3440;
  --c-text: #4E5969;
  --c-muted: #86909C;
  --c-faint: #A9B0BA;
  --c-bg: #FFFFFF;
  --c-bg-soft: #FAF9F7;
  --c-bg-tile: #FDF3EA;
  --c-border: #E8E4DE;
  --c-border-strong: #D9D4CC;
  --c-success: #00B42A;
  --c-danger: #F53F3F;
  --c-dark: #1D2129;
  --c-dark-2: #262B33;
  --c-darkest: #14171C;
  --shadow-flat: 0 1px 2px rgba(29, 33, 41, 0.04), 0 6px 20px rgba(29, 33, 41, 0.05);
  --shadow-lift: 0 2px 4px rgba(29, 33, 41, 0.06), 0 12px 32px rgba(29, 33, 41, 0.10);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 16px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", "Helvetica Neue", Arial, sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --container: 1200px;
  --header-h: 68px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-text);
  background: var(--c-bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; height: auto; display: block; border: 0; }
a { color: var(--c-primary); text-decoration: none; transition: color .18s ease; }
a:hover { color: var(--c-primary-hover); }
ul, ol { list-style: none; }
button { font-family: inherit; cursor: pointer; border: 0; background: none; }

::selection { background: rgba(240, 96, 0, .18); }

:focus-visible { outline: 2px solid var(--c-primary); outline-offset: 2px; border-radius: 4px; }

.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 24px; }

/* ---------- 2. 排版 ---------- */
h1, h2, h3, h4, h5 { color: var(--c-ink); font-weight: 700; line-height: 1.3; }

.h1 { font-size: 44px; letter-spacing: -.5px; }
.h2 { font-size: 32px; letter-spacing: -.3px; }
.h3 { font-size: 21px; }

.section { padding: 88px 0; }
.section-soft { background: var(--c-bg-soft); }

.section-head { max-width: 720px; margin: 0 auto 56px; text-align: center; }
.section-head .h2 { margin-bottom: 14px; }
.section-head p { color: var(--c-muted); font-size: 16.5px; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--c-primary);
  margin-bottom: 14px;
}
.eyebrow::before { content: ""; width: 22px; height: 2px; background: var(--c-primary); }

.lead { font-size: 17px; }

.text-accent { color: var(--c-primary); }

/* ---------- 3. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  height: 48px;
  padding: 0 28px;
  border-radius: var(--radius-sm);
  font-size: 16px;
  font-weight: 600;
  line-height: 1;
  white-space: nowrap;
  transition: all .18s ease;
  border: 1px solid transparent;
}
.btn svg { flex: 0 0 auto; }

.btn-primary {
  background: var(--c-primary);
  color: #fff;
  box-shadow: 0 6px 18px rgba(240, 96, 0, .28);
}
.btn-primary:hover {
  background: var(--c-primary-hover);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(240, 96, 0, .34);
}
.btn-primary:active { background: var(--c-primary-active); transform: translateY(0); }

.btn-ghost {
  background: #fff;
  color: var(--c-ink);
  border-color: var(--c-border-strong);
}
.btn-ghost:hover { color: var(--c-primary); border-color: var(--c-primary); background: var(--c-primary-soft); }

.btn-lg { height: 54px; padding: 0 36px; font-size: 17px; border-radius: 10px; }
.btn-sm { height: 40px; padding: 0 20px; font-size: 14.5px; }

.btn-block { width: 100%; }

/* ---------- 4. 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(255, 255, 255, .96);
  backdrop-filter: saturate(1.4) blur(10px);
  -webkit-backdrop-filter: saturate(1.4) blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s ease, box-shadow .2s ease;
}
.site-header.is-scrolled { border-bottom-color: var(--c-border); box-shadow: 0 4px 18px rgba(29, 33, 41, .05); }

.nav-wrap { display: flex; align-items: center; justify-content: space-between; height: var(--header-h); gap: 24px; }

.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--c-ink); }
.brand:hover { color: var(--c-ink); }
.brand-logo {
  width: 38px; height: 38px;
  border-radius: 9px;
  background: #fff;
  border: 1px solid var(--c-border);
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
  flex: 0 0 auto;
}
.brand-logo img { width: 34px; height: 34px; }
.brand-name { font-size: 20px; font-weight: 800; letter-spacing: -.2px; }
.brand-name small { font-size: 11px; font-weight: 500; color: var(--c-muted); display: block; letter-spacing: 1.5px; margin-top: -3px; }

.main-nav { display: flex; align-items: center; gap: 6px; }
.main-nav a {
  color: var(--c-text);
  font-size: 15.5px;
  font-weight: 500;
  padding: 8px 16px;
  border-radius: 8px;
  transition: all .16s ease;
}
.main-nav a:hover { color: var(--c-primary); background: var(--c-primary-soft); }
.main-nav a.is-active { color: var(--c-primary); font-weight: 600; }

.nav-actions { display: flex; align-items: center; gap: 14px; }
.nav-download .btn { height: 42px; padding: 0 22px; font-size: 15px; }

.nav-toggle { display: none; width: 42px; height: 42px; border-radius: 8px; color: var(--c-ink); align-items: center; justify-content: center; }
.nav-toggle:hover { background: var(--c-bg-soft); }

/* ---------- 5. 首页 Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 84px 0 72px;
  background:
    radial-gradient(640px 340px at 88% -10%, rgba(240, 96, 0, .07), transparent 65%),
    radial-gradient(520px 300px at -6% 108%, rgba(245, 168, 0, .06), transparent 60%),
    #fff;
}
.hero-inner { display: grid; grid-template-columns: 1.02fr .98fr; gap: 64px; align-items: center; }

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 7px 16px 7px 10px;
  background: var(--c-primary-soft);
  border: 1px solid rgba(240, 96, 0, .25);
  border-radius: 999px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--c-primary-hover);
  margin-bottom: 26px;
}
.hero-badge .tag-solid {
  background: var(--c-primary);
  color: #fff;
  font-size: 12px;
  padding: 2px 10px;
  border-radius: 999px;
  letter-spacing: .5px;
}

.hero h1 { font-size: 46px; line-height: 1.24; letter-spacing: -.6px; margin-bottom: 22px; }
.hero h1 em { font-style: normal; color: var(--c-primary); position: relative; }
.hero .lead { font-size: 17.5px; max-width: 540px; margin-bottom: 36px; }
.hero .lead b { color: var(--c-ink); font-weight: 600; }

.hero-actions { display: flex; flex-wrap: wrap; gap: 16px; align-items: center; margin-bottom: 34px; }

.hero-meta { display: flex; flex-wrap: wrap; gap: 22px 34px; }
.hero-meta li { display: flex; align-items: center; gap: 9px; font-size: 14px; color: var(--c-muted); }
.hero-meta svg { color: var(--c-primary); flex: 0 0 auto; }

.hero-visual { position: relative; }
.hero-shot {
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lift);
  overflow: hidden;
  background: #fff;
}
.hero-shot img { width: 100%; }

.hero-shot-tag {
  position: absolute;
  right: 18px;
  bottom: -16px;
  background: var(--c-dark);
  color: #fff;
  font-size: 12.5px;
  padding: 7px 16px;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  box-shadow: var(--shadow-lift);
}
.hero-shot-tag .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--c-amber); }

.hero-float {
  position: absolute;
  left: -26px;
  top: 34px;
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lift);
  padding: 13px 18px;
  display: flex;
  align-items: center;
  gap: 12px;
  z-index: 2;
}
.hero-float .ico {
  width: 38px; height: 38px;
  border-radius: 9px;
  background: var(--c-bg-tile);
  color: var(--c-primary);
  display: flex; align-items: center; justify-content: center;
}
.hero-float .tt { font-size: 13.5px; font-weight: 700; color: var(--c-ink); line-height: 1.35; }
.hero-float .st { font-size: 12px; color: var(--c-muted); }

/* ---------- 6. 数据带 ---------- */
.stats-band { background: var(--c-dark); padding: 58px 0; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px; }
.stat { text-align: center; position: relative; }
.stat + .stat::before {
  content: "";
  position: absolute;
  left: -16px;
  top: 50%;
  transform: translateY(-50%);
  width: 1px;
  height: 44px;
  background: rgba(255, 255, 255, .12);
}
.stat .num { font-size: 38px; font-weight: 800; color: var(--c-primary); letter-spacing: -.5px; line-height: 1.2; font-variant-numeric: tabular-nums; }
.stat .num small { font-size: 20px; font-weight: 700; }
.stat .cap { color: #B8BEC7; font-size: 14px; margin-top: 6px; }

/* ---------- 7. 通用卡片（场景） ---------- */
.cards-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.cards-grid.cols-2 { grid-template-columns: repeat(2, 1fr); }

.card {
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 30px 28px;
  transition: all .2s ease;
}
.card:hover {
  border-color: rgba(240, 96, 0, .45);
  box-shadow: var(--shadow-lift);
  transform: translateY(-3px);
}
.card .ico {
  width: 52px; height: 52px;
  border-radius: 12px;
  background: var(--c-bg-tile);
  color: var(--c-primary);
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 20px;
}
.card h3 { font-size: 18.5px; margin-bottom: 10px; }
.card p { font-size: 15px; color: var(--c-muted); }

/* ---------- 8. 优势列表 ---------- */
.adv-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 22px 44px; }
.adv { display: flex; gap: 20px; padding: 26px; border-radius: var(--radius); border: 1px solid transparent; transition: all .2s ease; }
.adv:hover { background: #fff; border-color: var(--c-border); box-shadow: var(--shadow-flat); }
.adv-no {
  flex: 0 0 auto;
  width: 46px; height: 46px;
  border-radius: 12px;
  border: 2px solid var(--c-primary);
  color: var(--c-primary);
  font-size: 17px;
  font-weight: 800;
  display: flex; align-items: center; justify-content: center;
  background: #fff;
}
.adv h3 { font-size: 18px; margin-bottom: 8px; }
.adv p { font-size: 14.5px; color: var(--c-muted); }

/* ---------- 9. CTA 横幅 ---------- */
.cta-band { padding: 80px 0; }
.cta-box {
  background: var(--c-dark);
  border-radius: 20px;
  padding: 64px 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  position: relative;
  overflow: hidden;
}
.cta-box::before {
  content: "";
  position: absolute;
  right: -80px;
  top: -80px;
  width: 260px;
  height: 260px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(240, 96, 0, .35), transparent 68%);
}
.cta-box::after {
  content: "";
  position: absolute;
  left: 32%;
  bottom: -120px;
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(245, 168, 0, .16), transparent 70%);
}
.cta-box > * { position: relative; z-index: 1; }
.cta-box h2 { color: #fff; font-size: 30px; margin-bottom: 12px; letter-spacing: -.3px; }
.cta-box p { color: #AEB6C0; font-size: 16px; max-width: 520px; }
.cta-box p b { color: #E8EBEF; font-weight: 600; }
.cta-actions { display: flex; flex-direction: column; gap: 12px; align-items: stretch; min-width: 250px; }
.cta-note { color: #8A919C; font-size: 13px; text-align: center; }

/* ---------- 10. 页脚 ---------- */
.site-footer { background: var(--c-darkest); color: #9AA1AB; padding: 72px 0 0; font-size: 14.5px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 48px; padding-bottom: 56px; }
.footer-brand .brand-name { color: #fff; }
.footer-brand p { margin: 18px 0 22px; color: #8A919C; font-size: 14px; line-height: 1.8; }
.footer-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: 1px solid rgba(255, 255, 255, .14);
  border-radius: 8px;
  padding: 8px 14px;
  font-size: 12.5px;
  color: #AEB6C0;
}
.footer-badge svg { color: var(--c-amber); }

.footer-col h4 { color: #fff; font-size: 15px; font-weight: 600; margin-bottom: 20px; letter-spacing: .5px; }
.footer-col li { margin-bottom: 12px; }
.footer-col a { color: #9AA1AB; font-size: 14.5px; transition: color .16s ease; }
.footer-col a:hover { color: var(--c-primary); }

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, .08);
  padding: 24px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 13px;
  color: #7B828C;
}
.footer-bottom a { color: #9AA1AB; }
.footer-bottom a:hover { color: var(--c-primary); }

/* ---------- 11. 子页头部 ---------- */
.page-hero {
  padding: 72px 0 60px;
  background:
    radial-gradient(560px 280px at 92% -20%, rgba(240, 96, 0, .07), transparent 60%),
    var(--c-bg-soft);
  border-bottom: 1px solid var(--c-border);
  text-align: center;
}
.page-hero .crumb { margin-bottom: 22px; font-size: 13.5px; color: var(--c-muted); }
.page-hero .crumb a { color: var(--c-muted); }
.page-hero .crumb a:hover { color: var(--c-primary); }
.page-hero .crumb .sep { margin: 0 8px; color: var(--c-faint); }
.page-hero h1 { font-size: 38px; letter-spacing: -.4px; margin-bottom: 16px; }
.page-hero p { max-width: 680px; margin: 0 auto; color: var(--c-muted); font-size: 16.5px; }

/* ---------- 12. 功能页 ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.feature-grid.cols-2 { grid-template-columns: repeat(2, 1fr); }

.spec-table { width: 100%; border-collapse: collapse; background: #fff; border: 1px solid var(--c-border); border-radius: var(--radius); overflow: hidden; }
.spec-table th, .spec-table td { padding: 15px 24px; text-align: left; font-size: 15px; border-bottom: 1px solid var(--c-border); }
.spec-table tr:last-child td { border-bottom: 0; }
.spec-table th { width: 200px; background: var(--c-bg-soft); color: var(--c-ink); font-weight: 600; }
.spec-table td { color: var(--c-text); }
.spec-table td code { font-family: var(--mono); font-size: 13.5px; background: var(--c-bg-soft); padding: 2px 8px; border-radius: 5px; color: var(--c-primary-hover); }

.code-block {
  background: var(--c-dark);
  color: #D7DCE3;
  border-radius: var(--radius);
  padding: 22px 26px;
  font-family: var(--mono);
  font-size: 14px;
  line-height: 2;
  overflow-x: auto;
}
.code-block .cm { color: #7B828C; }
.code-block .k { color: #F5A800; }
.code-block .v { color: #7ECB8F; }

.split { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.split .h2 { font-size: 28px; margin-bottom: 16px; }
.split p + p { margin-top: 12px; }

.check-list li { display: flex; gap: 12px; margin-bottom: 14px; font-size: 15.5px; }
.check-list svg { color: var(--c-success); flex: 0 0 auto; margin-top: 5px; }
.check-list b { color: var(--c-ink); font-weight: 600; }

/* ---------- 13. 下载页 ---------- */
.dl-hero {
  background:
    radial-gradient(640px 320px at 85% -20%, rgba(240, 96, 0, .08), transparent 62%),
    var(--c-dark);
  color: #fff;
  padding: 76px 0 64px;
  text-align: center;
}
.dl-hero .ver-pill {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: rgba(255, 255, 255, .08);
  border: 1px solid rgba(255, 255, 255, .16);
  color: #E8EBEF;
  border-radius: 999px;
  padding: 7px 18px;
  font-size: 13.5px;
  font-weight: 600;
  margin-bottom: 24px;
}
.dl-hero .ver-pill .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--c-primary); }
.dl-hero h1 { color: #fff; font-size: 40px; letter-spacing: -.4px; margin-bottom: 14px; }
.dl-hero p { color: #AEB6C0; max-width: 640px; margin: 0 auto 34px; }

.dl-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 26px; margin-top: -56px; position: relative; z-index: 2; }
.dl-card {
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  padding: 36px 34px;
  box-shadow: var(--shadow-lift);
  display: flex;
  flex-direction: column;
}
.dl-card .dl-head { display: flex; align-items: center; gap: 16px; margin-bottom: 18px; }
.dl-card .ico {
  width: 54px; height: 54px;
  border-radius: 13px;
  background: var(--c-bg-tile);
  color: var(--c-primary);
  display: flex; align-items: center; justify-content: center;
}
.dl-card h2 { font-size: 21px; }
.dl-card .dl-sub { font-size: 13.5px; color: var(--c-muted); }
.dl-card .rec {
  margin-left: auto;
  background: var(--c-primary);
  color: #fff;
  font-size: 12px;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 999px;
  letter-spacing: 1px;
}
.dl-card .dl-desc { color: var(--c-muted); font-size: 14.5px; margin-bottom: 22px; flex: 1; }

.dl-info {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 22px;
  background: var(--c-bg-soft);
  border-radius: 10px;
  padding: 14px 8px;
}
.dl-info div { text-align: center; }
.dl-info .k { font-size: 12px; color: var(--c-muted); display: block; }
.dl-info .v { font-size: 13.5px; font-weight: 600; color: var(--c-ink); font-family: var(--mono); }

.dl-links { display: grid; gap: 10px; }
.dl-alt { text-align: center; font-size: 13px; color: var(--c-muted); margin-top: 14px; }
.dl-alt a { color: var(--c-muted); text-decoration: underline; text-underline-offset: 3px; }
.dl-alt a:hover { color: var(--c-primary); }

.qr-section { display: grid; grid-template-columns: repeat(2, minmax(0, 380px)); gap: 26px; justify-content: center; }
.qr-card {
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  padding: 34px;
  text-align: center;
}
.qr-card img {
  width: 190px;
  height: 190px;
  margin: 0 auto 20px;
  border-radius: 12px;
  border: 1px solid var(--c-border);
  padding: 10px;
}
.qr-card h3 { font-size: 18px; margin-bottom: 6px; }
.qr-card p { font-size: 13.5px; color: var(--c-muted); margin-bottom: 18px; }
.qr-card .btn { width: 100%; }

.hash-box {
  background: var(--c-bg-soft);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 20px 24px;
}
.hash-box h4 { font-size: 15px; margin-bottom: 12px; display: flex; align-items: center; gap: 8px; }
.hash-box h4 svg { color: var(--c-primary); }
.hash-row { display: flex; gap: 14px; align-items: baseline; margin-bottom: 10px; font-size: 13px; flex-wrap: wrap; }
.hash-row:last-child { margin-bottom: 0; }
.hash-row .fn { font-family: var(--mono); color: var(--c-ink); font-weight: 600; white-space: nowrap; }
.hash-row code { font-family: var(--mono); color: var(--c-muted); word-break: break-all; }

/* 版本历史 */
.timeline { position: relative; max-width: 860px; margin: 0 auto; padding-left: 26px; }
.timeline::before { content: ""; position: absolute; left: 5px; top: 8px; bottom: 8px; width: 2px; background: var(--c-border-strong); }
.tl-item { position: relative; padding: 0 0 34px 26px; }
.tl-item:last-child { padding-bottom: 0; }
.tl-item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 7px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #fff;
  border: 3px solid var(--c-primary);
}
.tl-item.tl-pre::before { border-color: var(--c-faint); }
.tl-head { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin-bottom: 8px; }
.tl-head .ver { font-size: 17px; font-weight: 700; color: var(--c-ink); font-family: var(--mono); }
.tl-head .date { font-size: 13px; color: var(--c-muted); }
.tl-tag {
  font-size: 11.5px;
  font-weight: 600;
  padding: 2px 10px;
  border-radius: 999px;
  letter-spacing: .5px;
}
.tl-tag.stable { background: rgba(0, 180, 42, .1); color: var(--c-success); }
.tl-tag.pre { background: var(--c-bg-soft); color: var(--c-muted); border: 1px solid var(--c-border); }
.tl-tag.latest { background: rgba(240, 96, 0, .1); color: var(--c-primary); }
.tl-item ul { margin-top: 6px; }
.tl-item li { font-size: 14.5px; color: var(--c-muted); padding-left: 16px; position: relative; margin-bottom: 4px; }
.tl-item li::before { content: ""; position: absolute; left: 0; top: 11px; width: 6px; height: 2px; background: var(--c-faint); }

/* ---------- 14. 指南页 ---------- */
.steps-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; counter-reset: step; }
.step {
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 28px 24px;
  position: relative;
  counter-increment: step;
}
.step::before {
  content: counter(step, decimal-leading-zero);
  font-size: 44px;
  font-weight: 800;
  color: var(--c-primary-soft);
  -webkit-text-stroke: 1.2px rgba(240, 96, 0, .55);
  display: block;
  line-height: 1;
  margin-bottom: 16px;
}
.step h3 { font-size: 17px; margin-bottom: 8px; }
.step p { font-size: 14px; color: var(--c-muted); }

.faq-list { max-width: 860px; margin: 0 auto; }
.faq-item {
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius-sm);
  margin-bottom: 14px;
  overflow: hidden;
  transition: border-color .2s ease;
}
.faq-item[open] { border-color: rgba(240, 96, 0, .5); }
.faq-item summary {
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 19px 24px;
  font-size: 16px;
  font-weight: 600;
  color: var(--c-ink);
  cursor: pointer;
  user-select: none;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary:hover { color: var(--c-primary); }
.faq-item summary .chev {
  flex: 0 0 auto;
  width: 28px; height: 28px;
  border-radius: 50%;
  background: var(--c-bg-soft);
  color: var(--c-muted);
  display: flex; align-items: center; justify-content: center;
  transition: all .2s ease;
}
.faq-item[open] summary .chev { background: var(--c-primary); color: #fff; transform: rotate(180deg); }
.faq-body { padding: 0 24px 22px; font-size: 15px; color: var(--c-text); }
.faq-body p + p { margin-top: 10px; }
.faq-body ul { margin: 10px 0; }
.faq-body li { padding-left: 18px; position: relative; margin-bottom: 6px; font-size: 14.5px; }
.faq-body li::before { content: ""; position: absolute; left: 2px; top: 12px; width: 6px; height: 2px; background: var(--c-primary); }
.faq-body code { font-family: var(--mono); font-size: 13.5px; background: var(--c-bg-soft); padding: 2px 8px; border-radius: 5px; color: var(--c-primary-hover); }
.faq-body .note {
  background: var(--c-primary-soft);
  border-left: 3px solid var(--c-primary);
  border-radius: 0 8px 8px 0;
  padding: 12px 16px;
  font-size: 14px;
  margin-top: 12px;
  color: var(--c-ink-2);
}

/* ---------- 15. 关于页 ---------- */
.compare-table { width: 100%; border-collapse: collapse; background: #fff; border: 1px solid var(--c-border); border-radius: var(--radius); overflow: hidden; font-size: 14.5px; }
.compare-table th, .compare-table td { padding: 14px 20px; text-align: center; border-bottom: 1px solid var(--c-border); }
.compare-table thead th { background: var(--c-dark); color: #fff; font-weight: 600; font-size: 14.5px; }
.compare-table thead th:first-child { text-align: left; }
.compare-table tbody th { text-align: left; color: var(--c-ink); font-weight: 600; background: var(--c-bg-soft); }
.compare-table td { color: var(--c-text); }
.compare-table .yes { color: var(--c-success); font-weight: 600; }
.compare-table .no { color: var(--c-faint); }
.compare-table .hl { color: var(--c-primary); font-weight: 600; }
.compare-table tr:last-child td, .compare-table tr:last-child th { border-bottom: 0; }

.osi-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 18px 24px;
  font-size: 14px;
}
.osi-badge svg { color: var(--c-primary); }

.link-card {
  display: flex;
  align-items: center;
  gap: 16px;
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 22px 24px;
  transition: all .2s ease;
}
.link-card:hover { border-color: rgba(240, 96, 0, .45); box-shadow: var(--shadow-flat); transform: translateY(-2px); }
.link-card .ico {
  width: 46px; height: 46px;
  border-radius: 11px;
  background: var(--c-bg-tile);
  color: var(--c-primary);
  display: flex; align-items: center; justify-content: center;
  flex: 0 0 auto;
}
.link-card b { display: block; color: var(--c-ink); font-size: 15.5px; }
.link-card span { font-size: 13.5px; color: var(--c-muted); }
.link-card .arrow { margin-left: auto; color: var(--c-faint); transition: transform .2s ease, color .2s ease; }
.link-card:hover .arrow { color: var(--c-primary); transform: translateX(4px); }

/* ---------- 16. 下载弹窗 ---------- */
.modal {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  opacity: 0;
  visibility: hidden;
  transition: opacity .22s ease, visibility .22s ease;
}
.modal.is-open { opacity: 1; visibility: visible; }
.modal-mask { position: absolute; inset: 0; background: rgba(20, 23, 28, .62); backdrop-filter: blur(3px); }
.modal-card {
  position: relative;
  width: 100%;
  max-width: 620px;
  max-height: calc(100vh - 48px);
  overflow-y: auto;
  background: #fff;
  border-radius: 18px;
  box-shadow: 0 24px 64px rgba(20, 23, 28, .3);
  padding: 36px 36px 30px;
  transform: translateY(14px) scale(.98);
  transition: transform .22s ease;
}
.modal.is-open .modal-card { transform: translateY(0) scale(1); }

.modal-close {
  position: absolute;
  right: 16px;
  top: 16px;
  width: 36px; height: 36px;
  border-radius: 50%;
  color: var(--c-muted);
  display: flex; align-items: center; justify-content: center;
  transition: all .16s ease;
}
.modal-close:hover { background: var(--c-bg-soft); color: var(--c-ink); }

.modal-head { text-align: center; margin-bottom: 26px; }
.modal-head h3 { font-size: 23px; margin-bottom: 8px; }
.modal-head p { font-size: 14px; color: var(--c-muted); }
.modal-head .ver-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--c-primary-soft);
  color: var(--c-primary-hover);
  border-radius: 999px;
  font-size: 12.5px;
  font-weight: 600;
  padding: 4px 14px;
  margin-top: 10px;
}
.modal-head .ver-pill .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--c-primary); }

.modal-qr-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.modal-qr {
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 22px 18px;
  text-align: center;
  transition: all .2s ease;
}
.modal-qr:hover { border-color: rgba(240, 96, 0, .45); box-shadow: var(--shadow-flat); }
.modal-qr img { width: 148px; height: 148px; margin: 0 auto 14px; }
.modal-qr h4 { font-size: 15.5px; margin-bottom: 2px; }
.modal-qr .size { font-size: 12.5px; color: var(--c-muted); display: block; margin-bottom: 14px; }
.modal-qr .btn { height: 38px; padding: 0 18px; font-size: 13.5px; width: 100%; }

.modal-foot { margin-top: 22px; padding-top: 18px; border-top: 1px dashed var(--c-border); text-align: center; }
.modal-foot p { font-size: 12.5px; color: var(--c-muted); line-height: 1.9; }
.modal-foot p b { color: var(--c-ink); font-weight: 600; }
.modal-foot a { color: var(--c-muted); text-decoration: underline; text-underline-offset: 3px; }

body.modal-open { overflow: hidden; }

/* ---------- 17. 动效 ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .6s ease, transform .6s ease; }
.reveal.is-visible { opacity: 1; transform: translateY(0); }
.reveal-d1 { transition-delay: .08s; }
.reveal-d2 { transition-delay: .16s; }
.reveal-d3 { transition-delay: .24s; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .btn, .card, .adv, .link-card { transition: none; }
}

/* ---------- 18. 响应式 ---------- */
@media (max-width: 1080px) {
  .hero-inner { grid-template-columns: 1fr; gap: 48px; }
  .hero { padding: 64px 0 60px; }
  .hero .lead { max-width: 640px; }
  .hero-visual { max-width: 640px; }
  .hero-float { display: none; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 40px 24px; }
  .stat + .stat::before { display: none; }
  .cards-grid, .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .steps-grid { grid-template-columns: repeat(2, 1fr); }
  .split { grid-template-columns: 1fr; gap: 36px; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 40px; }
}

@media (max-width: 820px) {
  .main-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: #fff;
    border-bottom: 1px solid var(--c-border);
    box-shadow: var(--shadow-lift);
    flex-direction: column;
    align-items: stretch;
    padding: 12px 20px 20px;
    gap: 4px;
    transform: translateY(-8px);
    opacity: 0;
    visibility: hidden;
    transition: all .22s ease;
  }
  .main-nav.is-open { transform: translateY(0); opacity: 1; visibility: visible; }
  .main-nav a { padding: 12px 14px; font-size: 16px; }
  .nav-toggle { display: inline-flex; }
  .nav-download .btn span { display: none; }
  .nav-download .btn { padding: 0 14px; }
  .section { padding: 64px 0; }
  .section-head { margin-bottom: 40px; }
  .h1, .hero h1 { font-size: 34px; }
  .h2 { font-size: 27px; }
  .page-hero h1 { font-size: 30px; }
  .dl-hero h1 { font-size: 30px; }
  .adv-grid, .cards-grid, .feature-grid, .dl-grid, .steps-grid, .qr-section { grid-template-columns: 1fr; }
  .cta-box { flex-direction: column; text-align: center; padding: 48px 28px; }
  .cta-box p { margin: 0 auto; }
  .cta-actions { width: 100%; }
  .footer-grid { grid-template-columns: 1fr; gap: 34px; }
  .footer-bottom { justify-content: center; text-align: center; }
  .modal-card { padding: 28px 20px 24px; }
  .modal-qr-grid { grid-template-columns: 1fr; }
  .compare-table { font-size: 13px; }
  .compare-table th, .compare-table td { padding: 11px 12px; }
  .spec-table th, .spec-table td { padding: 12px 16px; font-size: 14px; }
  .spec-table th { width: 120px; }
  .dl-info { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 480px) {
  .container { padding: 0 18px; }
  .hero h1 { font-size: 30px; }
  .hero-actions .btn { width: 100%; }
  .stats-grid { grid-template-columns: 1fr 1fr; gap: 28px 16px; }
  .stat .num { font-size: 30px; }
  .cards-grid, .feature-grid, .steps-grid { grid-template-columns: 1fr; }
  .brand-name small { display: none; }
}