/*!
 * OSGKeyboard 主页设计系统（2026-09 重设计）
 * 方向：Apple 式产品页 —— 深色产品舞台 + 实机画面优先 + 滚动叙事。
 * 主题跟随系统（site.js 可手动覆盖）；Hero / 隐私 / 下载区块在两种
 * 主题下都使用固定的深色「舞台」调色板，与新应用图标同一语言。
 */

/* --------------------------------------------------------------------------
 * 1. 设计令牌
 * -------------------------------------------------------------------------- */
:root {
  color-scheme: light dark;
  --canvas: #f3f5f7;
  --surface: #ffffff;
  --surface-soft: #eceff3;
  --surface-strong: #e4e9ee;
  --ink: #0f1214;
  --ink-2: #55606a;
  --ink-3: #8a939c;
  --line: rgba(15, 18, 20, 0.09);
  --line-strong: rgba(15, 18, 20, 0.16);
  --accent: #2c8a52;
  --accent-strong: #217142;
  --accent-soft: rgba(44, 138, 82, 0.12);
  /* 深色舞台：Hero / 隐私 / 下载共用，两种主题下保持一致 */
  --stage-1: #272d35;
  --stage-2: #14171c;
  --stage-3: #0c0e12;
  --stage-ink: #f4f6f7;
  --stage-ink-2: #a7b0b9;
  --stage-line: rgba(255, 255, 255, 0.1);
  --stage-accent: #6fc491;
  --content: min(1120px, calc(100vw - 48px));
  --radius-xl: 28px;
  --radius-lg: 22px;
  --radius-md: 14px;
  --shadow-card: 0 28px 56px -28px rgba(16, 20, 24, 0.25);
  --shadow-media: 0 32px 64px -32px rgba(16, 20, 24, 0.35);
}

html[data-theme="dark"] {
  --canvas: #0e1013;
  --surface: #16191d;
  --surface-soft: #12151a;
  --surface-strong: #20252b;
  --ink: #f2f4f5;
  --ink-2: #a4adb5;
  --ink-3: #7c858d;
  --line: rgba(255, 255, 255, 0.09);
  --line-strong: rgba(255, 255, 255, 0.16);
  --accent: #68bf8d;
  --accent-strong: #7dcd9e;
  --accent-soft: rgba(104, 191, 141, 0.14);
  --shadow-card: 0 28px 56px -28px rgba(0, 0, 0, 0.6);
  --shadow-media: 0 32px 64px -32px rgba(0, 0, 0, 0.65);
}

/* --------------------------------------------------------------------------
 * 2. 基础排版
 * -------------------------------------------------------------------------- */
* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 84px;
  background: var(--canvas);
}

body {
  margin: 0;
  overflow-x: hidden;
  background: var(--canvas);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC",
    "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

html[data-lang="en"] body {
  font-family: "Outfit", -apple-system, BlinkMacSystemFont, "SF Pro Text",
    "Helvetica Neue", Arial, sans-serif;
}

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

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button {
  color: inherit;
  font: inherit;
}

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

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  text-wrap: balance;
}

html[data-lang="zh"] h1,
html[data-lang="zh"] h2,
html[data-lang="zh"] h3 {
  overflow-wrap: normal;
  word-break: keep-all;
}

::selection {
  background: var(--accent);
  color: #fff;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

.skip-link {
  position: fixed;
  z-index: 100;
  top: 12px;
  left: 12px;
  padding: 9px 14px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--canvas);
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: translateY(0);
}

/* 内联 SVG 图标库容器：不可见但可被 <use> 引用 */
.svg-defs {
  position: absolute;
  width: 0;
  height: 0;
  overflow: hidden;
}

/* 内联 SVG 图标系统：currentColor 描边，随主题变色 */
.i {
  width: 1.25em;
  height: 1.25em;
  flex: none;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
  vertical-align: -0.28em;
}

/* --------------------------------------------------------------------------
 * 3. 导航
 * -------------------------------------------------------------------------- */
/* Hero 是深色舞台：导航在页面顶部时按深色舞台配色，滚动后切换为主题色 */
.site-nav {
  position: fixed;
  z-index: 50;
  top: 0;
  right: 0;
  left: 0;
  border-bottom: 1px solid transparent;
  color: var(--stage-ink);
  transition: background 0.35s ease, border-color 0.35s ease, color 0.35s ease;
}

.site-nav.is-scrolled {
  border-bottom-color: var(--line);
  background: color-mix(in srgb, var(--canvas) 78%, transparent);
  color: var(--ink);
  -webkit-backdrop-filter: blur(20px) saturate(1.6);
  backdrop-filter: blur(20px) saturate(1.6);
}

.nav-shell {
  display: flex;
  width: var(--content);
  height: 64px;
  align-items: center;
  justify-content: space-between;
  margin: 0 auto;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 0.98rem;
  font-weight: 650;
  letter-spacing: -0.01em;
}

.brand img {
  width: 30px;
  height: 30px;
  border-radius: 8px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-links a {
  padding: 8px 14px;
  border-radius: 999px;
  font-size: 0.92rem;
  opacity: 0.72;
  transition: opacity 0.2s ease, background 0.2s ease;
}

.nav-links a:hover {
  opacity: 1;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.icon-button,
.language-button {
  display: inline-grid;
  min-width: 38px;
  height: 38px;
  align-items: center;
  justify-content: center;
  padding: 0;
  border: 0;
  border-radius: 999px;
  background: transparent;
  cursor: pointer;
  opacity: 0.78;
  transition: opacity 0.2s ease, background 0.2s ease;
}

.language-button {
  font-size: 0.82rem;
  font-weight: 650;
  letter-spacing: 0.02em;
}

.icon-button:hover,
.language-button:hover {
  opacity: 1;
}

.icon-button .i {
  width: 19px;
  height: 19px;
}

.mobile-menu-button {
  display: none;
}

.mobile-nav {
  display: none;
}

/* --------------------------------------------------------------------------
 * 4. Hero —— 深色产品舞台
 * -------------------------------------------------------------------------- */
.hero {
  position: relative;
  display: flex;
  min-height: 100svh;
  flex-direction: column;
  align-items: center;
  padding: 148px 0 0;
  overflow: hidden;
  background:
    radial-gradient(120% 90% at 50% 110%, rgba(111, 196, 145, 0.14), transparent 55%),
    linear-gradient(180deg, var(--stage-1) 0%, var(--stage-2) 52%, var(--stage-3) 100%);
  color: var(--stage-ink);
  text-align: center;
}

.hero-glow {
  position: absolute;
  top: -320px;
  left: 50%;
  width: 900px;
  height: 640px;
  border-radius: 50%;
  background: radial-gradient(closest-side, rgba(111, 196, 145, 0.16), transparent 70%);
  pointer-events: none;
  transform: translateX(-50%);
}

.hero-inner {
  position: relative;
  width: var(--content);
}

.launch-pill {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 28px;
  padding: 8px 16px;
  border: 1px solid var(--stage-line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  color: var(--stage-ink-2);
  font-size: 0.82rem;
  font-weight: 550;
  letter-spacing: 0.01em;
}

.launch-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--stage-accent);
  box-shadow: 0 0 12px rgba(111, 196, 145, 0.9);
}

.hero h1 {
  margin-bottom: 22px;
  font-size: clamp(2.7rem, 6.2vw, 4.5rem);
  font-weight: 700;
  letter-spacing: -0.032em;
  line-height: 1.06;
}

.hero h1 span {
  display: block;
}

.hero-muted {
  margin-top: 10px;
  color: var(--stage-ink-2);
  font-size: clamp(1.35rem, 2.8vw, 2.1rem);
  font-weight: 600;
  letter-spacing: -0.02em;
}

.hero-copy {
  max-width: 620px;
  margin: 0 auto 36px;
  color: var(--stage-ink-2);
  font-size: 1.08rem;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 18px;
  margin-bottom: 30px;
}

.store-badge {
  display: inline-flex;
  transition: transform 0.25s ease;
}

.store-badge:hover {
  transform: translateY(-2px);
}

.store-badge img {
  width: 171px;
  height: 48px;
}

.ghost-action {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  border: 1px solid var(--stage-line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  color: var(--stage-ink);
  font-size: 0.95rem;
  font-weight: 600;
  transition: background 0.25s ease, transform 0.25s ease;
}

.ghost-action:hover {
  background: rgba(255, 255, 255, 0.12);
  transform: translateY(-2px);
}

.ghost-action .i {
  width: 17px;
  height: 17px;
}

.text-action {
  color: var(--stage-ink-2);
  font-size: 0.95rem;
  font-weight: 550;
  text-decoration: underline;
  text-decoration-color: var(--stage-line);
  text-underline-offset: 5px;
  transition: color 0.2s ease;
}

.text-action:hover {
  color: var(--stage-ink);
}

.hero-trust {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px 28px;
  margin: 0 0 52px;
  padding: 0;
  color: var(--stage-ink-2);
  font-size: 0.86rem;
  list-style: none;
}

.hero-trust li {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}

.hero-trust .i {
  width: 16px;
  height: 16px;
  color: var(--stage-accent);
}

.hero-devices {
  position: relative;
  width: min(1060px, 94vw);
  margin: auto 0 0;
}

.hero-devices img {
  width: 100%;
  height: auto;
  filter: drop-shadow(0 48px 80px rgba(0, 0, 0, 0.5));
}

/* --------------------------------------------------------------------------
 * 5. 通用区块节奏
 * -------------------------------------------------------------------------- */
.section {
  padding: clamp(88px, 11vw, 136px) 0;
}

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

.section-inner {
  width: var(--content);
  margin: 0 auto;
}

.eyebrow {
  margin-bottom: 14px;
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 650;
  letter-spacing: 0.06em;
}

h2 {
  margin-bottom: 18px;
  font-size: clamp(1.9rem, 3.8vw, 2.8rem);
  font-weight: 700;
  letter-spacing: -0.024em;
  line-height: 1.14;
}

h3 {
  font-size: 1.12rem;
  font-weight: 650;
  letter-spacing: -0.01em;
}

.center-heading {
  max-width: 680px;
  margin: 0 auto clamp(48px, 6vw, 72px);
  text-align: center;
}

.center-heading p {
  color: var(--ink-2);
  font-size: 1.05rem;
}

/* 分栏布局：文案 + 媒体 */
.split-layout {
  display: grid;
  align-items: center;
  gap: clamp(40px, 6vw, 88px);
  grid-template-columns: 1.02fr 1fr;
}

.split-layout.reverse .feature-copy {
  order: 2;
}

.split-layout.reverse .media-frame {
  order: 1;
}

.feature-copy > p {
  color: var(--ink-2);
  font-size: 1.05rem;
}

.feature-note {
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  color: var(--ink-3);
  font-size: 0.92rem;
}

/* 实机媒体框：边框 + 定向长投影，呼应 iOS 端 2.1 的卡片层次 */
.media-frame {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--surface-strong);
  box-shadow: var(--shadow-media);
}

.media-frame video,
.media-frame img {
  width: 100%;
  height: auto;
}

/* --------------------------------------------------------------------------
 * 6. 四种输入方式速览
 * -------------------------------------------------------------------------- */
.ways-section {
  padding: clamp(64px, 8vw, 96px) 0;
}

.ways-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(4, 1fr);
}

.way-card {
  display: block;
  padding: 26px 24px 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--surface);
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.way-card:hover {
  border-color: var(--line-strong);
  box-shadow: var(--shadow-card);
  transform: translateY(-4px);
}

.way-card .i {
  width: 24px;
  height: 24px;
  margin-bottom: 16px;
  color: var(--accent);
}

.way-card h3 {
  margin-bottom: 6px;
}

.way-card p {
  margin: 0;
  color: var(--ink-2);
  font-size: 0.92rem;
  line-height: 1.55;
}

/* --------------------------------------------------------------------------
 * 7. 功能区块细节
 * -------------------------------------------------------------------------- */
.step-list {
  display: grid;
  gap: 20px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.step-list li {
  display: flex;
  align-items: flex-start;
  gap: 18px;
}

.step-index {
  padding-top: 2px;
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.04em;
}

.step-list h3 {
  margin-bottom: 4px;
}

.step-list p {
  margin: 0;
  color: var(--ink-2);
  font-size: 0.95rem;
}

.mini-feature {
  margin-top: 24px;
}

.mini-feature h3 {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 6px;
}

.mini-feature h3 .i {
  width: 19px;
  height: 19px;
  color: var(--accent);
}

.mini-feature p {
  margin: 0;
  color: var(--ink-2);
  font-size: 0.97rem;
}

.skill-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin: 26px 0 4px;
}

.skill-chips > span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  font-size: 0.88rem;
  font-weight: 550;
}

.skill-chips .i {
  width: 15px;
  height: 15px;
  color: var(--accent);
}

.quiet-list {
  display: grid;
  gap: 12px;
  margin: 24px 0 0;
  padding: 0;
  color: var(--ink-2);
  font-size: 0.95rem;
  list-style: none;
}

.quiet-list li {
  position: relative;
  padding-left: 26px;
}

.quiet-list li::before {
  position: absolute;
  top: 2px;
  left: 0;
  width: 16px;
  height: 16px;
  color: var(--accent);
  /* 内联 check 图标，避免外部字体依赖 */
  content: "";
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12.5l4.5 4.5L19 7.5'/%3E%3C/svg%3E") center / contain no-repeat;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M5 12.5l4.5 4.5L19 7.5'/%3E%3C/svg%3E") center / contain no-repeat;
  background: currentColor;
}

/* --------------------------------------------------------------------------
 * 8. 个人化（2.1 卖点）
 * -------------------------------------------------------------------------- */
.personal-grid {
  display: grid;
  gap: 20px;
  grid-template-columns: repeat(3, 1fr);
}

.personal-card {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: var(--surface);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.personal-card:hover {
  box-shadow: var(--shadow-card);
  transform: translateY(-4px);
}

.personal-media {
  overflow: hidden;
  aspect-ratio: 4 / 3;
  background: var(--surface-strong);
}

.personal-media img,
.personal-media video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
}

.personal-card h3 {
  margin: 22px 24px 8px;
}

.personal-card p {
  margin: 0;
  padding: 0 24px 26px;
  color: var(--ink-2);
  font-size: 0.94rem;
}

/* --------------------------------------------------------------------------
 * 9. 隐私：三种服务路径（深色舞台）
 * -------------------------------------------------------------------------- */
.privacy-section {
  background: linear-gradient(180deg, var(--stage-2), var(--stage-3));
  color: var(--stage-ink);
}

.center-heading.inverse p {
  color: var(--stage-ink-2);
}

.service-paths {
  display: grid;
  align-items: stretch;
  gap: 18px;
  grid-template-columns: 1.25fr 1fr 1fr;
}

.service-paths article {
  position: relative;
  padding: 30px 28px 26px;
  border: 1px solid var(--stage-line);
  border-radius: var(--radius-xl);
  background: rgba(255, 255, 255, 0.045);
}

.service-paths .path-primary {
  border-color: rgba(111, 196, 145, 0.35);
  background: rgba(111, 196, 145, 0.08);
}

.path-badge {
  position: absolute;
  top: 22px;
  right: 24px;
  padding: 4px 11px;
  border-radius: 999px;
  background: var(--stage-accent);
  color: #0c0e12;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.05em;
}

.path-icon {
  width: 26px;
  height: 26px;
  margin-bottom: 18px;
  color: var(--stage-accent);
}

.service-paths h3 {
  margin-bottom: 10px;
  font-size: 1.25rem;
}

.service-paths p {
  color: var(--stage-ink-2);
  font-size: 0.95rem;
}

.path-note {
  display: block;
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--stage-line);
  color: var(--stage-ink-2);
  font-size: 0.82rem;
  letter-spacing: 0.01em;
}

.privacy-proof {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  margin-top: 22px;
  padding: 26px 30px;
  border: 1px solid var(--stage-line);
  border-radius: var(--radius-xl);
  background: rgba(255, 255, 255, 0.045);
}

.privacy-proof > div {
  display: flex;
  align-items: center;
  gap: 16px;
}

.privacy-proof .i {
  width: 26px;
  height: 26px;
  flex: none;
  color: var(--stage-accent);
}

.privacy-proof h3 {
  margin: 0;
  font-size: 1.02rem;
  font-weight: 600;
  letter-spacing: 0;
}

.inverse-link {
  display: inline-flex;
  flex: none;
  align-items: center;
  gap: 7px;
  color: var(--stage-ink);
  font-size: 0.92rem;
  font-weight: 600;
  text-decoration: underline;
  text-decoration-color: var(--stage-line);
  text-underline-offset: 5px;
  transition: text-decoration-color 0.2s ease;
}

.inverse-link:hover {
  text-decoration-color: var(--stage-ink);
}

.inverse-link .i {
  width: 15px;
  height: 15px;
}

/* --------------------------------------------------------------------------
 * 10. 平台
 * -------------------------------------------------------------------------- */
.platform-grid {
  display: grid;
  gap: 20px;
  grid-template-columns: 1fr 1fr;
}

.platform-card {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: var(--surface);
}

.platform-card .media-frame {
  margin: 14px 14px 0;
  aspect-ratio: 4 / 3;
  border-radius: var(--radius-md);
  box-shadow: none;
}

.platform-card .media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
}

.platform-label {
  display: block;
  margin: 24px 28px 8px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.07em;
}

.platform-card h3 {
  margin: 0 28px 10px;
}

.platform-card > p {
  margin: 0;
  padding: 0 28px 30px;
  color: var(--ink-2);
  font-size: 0.95rem;
}

.platform-footnote {
  max-width: 720px;
  margin: 28px auto 0;
  color: var(--ink-3);
  font-size: 0.88rem;
  text-align: center;
}

/* --------------------------------------------------------------------------
 * 11. 稳定性信任条
 * -------------------------------------------------------------------------- */
.reliability-section {
  padding: clamp(48px, 6vw, 72px) 0;
}

.reliability-strip {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px 40px;
  padding: 26px 32px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: var(--surface);
}

.strip-title {
  flex: none;
  font-size: 0.95rem;
  font-weight: 650;
}

.reliability-strip ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 26px;
  margin: 0;
  padding: 0;
  color: var(--ink-2);
  font-size: 0.88rem;
  list-style: none;
}

.reliability-strip li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.reliability-strip li::before {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  content: "";
}

/* --------------------------------------------------------------------------
 * 12. FAQ
 * -------------------------------------------------------------------------- */
.faq-layout {
  display: grid;
  align-items: start;
  gap: clamp(40px, 6vw, 80px);
  grid-template-columns: 1fr 1.4fr;
}

.faq-item {
  border-top: 1px solid var(--line);
}

.faq-item:last-child {
  border-bottom: 1px solid var(--line);
}

.faq-item summary {
  position: relative;
  padding: 20px 40px 20px 0;
  cursor: pointer;
  font-size: 1.02rem;
  font-weight: 600;
  letter-spacing: -0.005em;
  list-style: none;
  transition: color 0.2s ease;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  position: absolute;
  top: 22px;
  right: 4px;
  width: 18px;
  height: 18px;
  color: var(--ink-3);
  content: "";
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M6 9.5l6 6 6-6'/%3E%3C/svg%3E") center / contain no-repeat;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M6 9.5l6 6 6-6'/%3E%3C/svg%3E") center / contain no-repeat;
  background: currentColor;
  transition: transform 0.3s ease;
}

.faq-item[open] summary::after {
  transform: rotate(180deg);
}

.faq-item summary:hover {
  color: var(--accent);
}

.faq-item p {
  margin: 0;
  padding: 0 32px 22px 0;
  color: var(--ink-2);
  font-size: 0.95rem;
}

/* --------------------------------------------------------------------------
 * 13. 下载 CTA（深色舞台，与 Hero 呼应）
 * -------------------------------------------------------------------------- */
.download-section {
  padding-top: 0;
}

.download-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  padding: clamp(40px, 6vw, 72px);
  border-radius: calc(var(--radius-xl) + 4px);
  background:
    radial-gradient(110% 130% at 90% 120%, rgba(111, 196, 145, 0.16), transparent 55%),
    linear-gradient(160deg, var(--stage-1), var(--stage-3));
  color: var(--stage-ink);
}

.download-panel h2 {
  margin-bottom: 12px;
}

.download-panel p {
  max-width: 460px;
  margin: 0;
  color: var(--stage-ink-2);
}

.download-panel .eyebrow {
  color: var(--stage-accent);
}

.download-actions {
  display: flex;
  flex: none;
  flex-direction: column;
  align-items: stretch;
  gap: 14px;
}

.outline-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 13px 22px;
  border: 1px solid var(--stage-line);
  border-radius: 999px;
  color: var(--stage-ink);
  font-size: 0.92rem;
  font-weight: 600;
  transition: background 0.25s ease;
}

.outline-action:hover {
  background: rgba(255, 255, 255, 0.08);
}

.outline-action .i {
  width: 16px;
  height: 16px;
}

/* --------------------------------------------------------------------------
 * 14. 页脚
 * -------------------------------------------------------------------------- */
.site-footer {
  padding: 44px 0 52px;
}

.footer-inner {
  display: flex;
  width: var(--content);
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin: 0 auto;
  color: var(--ink-3);
  font-size: 0.86rem;
}

.footer-links {
  display: flex;
  gap: 26px;
}

.footer-links a {
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--ink);
}

/* --------------------------------------------------------------------------
 * 15. 滚动显现动效（尊重减弱动效设置）
 * -------------------------------------------------------------------------- */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.85s cubic-bezier(0.16, 1, 0.3, 1),
    transform 0.85s cubic-bezier(0.16, 1, 0.3, 1);
  transition-delay: var(--d, 0s);
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .way-card,
  .personal-card,
  .store-badge,
  .ghost-action {
    transition: none;
  }
}

/* --------------------------------------------------------------------------
 * 16. 响应式
 * -------------------------------------------------------------------------- */
@media (max-width: 960px) {
  .nav-links {
    display: none;
  }

  .mobile-menu-button {
    display: inline-grid;
  }

  .mobile-nav {
    display: block;
    padding: 8px 24px 18px;
    border-bottom: 1px solid var(--line);
    background: color-mix(in srgb, var(--canvas) 88%, transparent);
    -webkit-backdrop-filter: blur(20px) saturate(1.6);
    backdrop-filter: blur(20px) saturate(1.6);
    color: var(--ink);
  }

  .mobile-nav a {
    display: block;
    padding: 12px 8px;
    border-radius: 10px;
    font-size: 1rem;
  }

  .split-layout,
  .faq-layout {
    grid-template-columns: 1fr;
  }

  .split-layout.reverse .feature-copy {
    order: 1;
  }

  .split-layout.reverse .media-frame {
    order: 2;
  }

  .ways-grid {
    grid-template-columns: 1fr 1fr;
  }

  .personal-grid {
    grid-template-columns: 1fr;
  }

  .service-paths {
    grid-template-columns: 1fr;
  }

  .platform-grid {
    grid-template-columns: 1fr;
  }

  .download-panel {
    flex-direction: column;
    align-items: flex-start;
  }

  .download-actions {
    align-items: flex-start;
  }

  .reliability-strip {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 600px) {
  :root {
    --content: calc(100vw - 40px);
  }

  .hero {
    padding-top: 120px;
  }

  .ways-grid {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    gap: 14px;
  }

  .privacy-proof {
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}