/* 官网首页（index.html / zh/index.html）样式，2026-09-25 第二版。
   原则：白底大留白、字重克制（700 封顶）、细线分隔代替一堆卡片，强调色 #1D4ED8 只用在少数地方；
   主视觉是真实的原文 / 译文对比图。隐私政策 / 服务条款 / tiktok.html 仍用 style.css，互不影响。 */
:root {
  --ink: #0B0B0C;
  --ink-2: #4A4A48;
  --ink-3: #6B6B67;
  --line: #E8E8E4;
  --soft: #F6F6F3;
  --accent: #1D4ED8;
  --accent-soft: #EEF2FF;
  --dark: #0B0D12;
  --maxw: 1200px;
  --gutter: 32px;
  --ease: cubic-bezier(.2, .7, .2, 1);
  color-scheme: light;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 84px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI Variable Text", "Segoe UI", Roboto, "Helvetica Neue", Arial,
               "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  font-size: 16px; line-height: 1.6; color: var(--ink); background: #fff;
  -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; text-rendering: optimizeLegibility;
}
h1, h2, h3 { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI Variable Display", "Segoe UI", Roboto,
             "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
             font-weight: 700; text-wrap: balance; }
p { text-wrap: pretty; }
img, svg { display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 8px; }
.lang-zh p, .lang-zh li { line-height: 1.75; }

.wrap { max-width: calc(var(--maxw) + var(--gutter) * 2); margin: 0 auto; padding: 0 var(--gutter); }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 12px; z-index: 100; padding: 8px 14px; border-radius: 8px; background: var(--ink); color: #fff; }

/* ---------------- 按钮 ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px; height: 52px; padding: 0 24px;
  border-radius: 999px; font-size: 16px; font-weight: 600; letter-spacing: -.005em; white-space: nowrap;
  transition: background-color .2s var(--ease), transform .2s var(--ease);
}
.btn svg { width: 18px; height: 18px; flex: none; }
.btn-primary { background: var(--ink); color: #fff; }
.btn-primary:hover { background: #2A2A2E; }
.btn-ghost { background: #fff; color: var(--ink); box-shadow: inset 0 0 0 1px #D8D8D3; }
.btn-ghost:hover { background: var(--soft); }
.btn:active { transform: scale(.98); }
.btn-sm { height: 40px; padding: 0 18px; font-size: 14px; }

/* ---------------- 顶栏 ---------------- */
.nav {
  position: sticky; top: 0; z-index: 50; background: rgba(255, 255, 255, .82);
  -webkit-backdrop-filter: saturate(1.8) blur(16px); backdrop-filter: saturate(1.8) blur(16px);
  border-bottom: 1px solid transparent; transition: border-color .2s;
}
.nav.scrolled { border-bottom-color: var(--line); }
.nav-row { display: flex; align-items: center; gap: 36px; height: 68px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 17px; font-weight: 650; letter-spacing: -.01em; white-space: nowrap; }
.brand img { width: 28px; height: 28px; border-radius: 7px; }
.nav-links { display: flex; gap: 28px; font-size: 15px; color: var(--ink-2); }
.nav-links a { transition: color .15s; }
.nav-links a:hover { color: var(--ink); }
.nav-end { display: flex; align-items: center; gap: 14px; margin-left: auto; }
.lang { display: inline-flex; gap: 2px; font-size: 14px; white-space: nowrap; }
.lang a { padding: 6px 8px; border-radius: 8px; color: var(--ink-3); }
.lang a:hover { color: var(--ink); }
.lang a[aria-current] { color: var(--ink); font-weight: 600; }

/* ---------------- 首屏 ---------------- */
.hero { position: relative; isolation: isolate; padding: 64px 0 88px; overflow: hidden; }
.hero-bg {   /* 柔和多彩：蓝 / 紫 / 粉 / 青四团很淡的光斑，和 App 的功能色同一组 */
  position: absolute; inset: -30% -10% 0 -10%; z-index: -1; pointer-events: none;
  background:
    radial-gradient(34% 42% at 14% 22%, rgba(37, 99, 235, .16), transparent 70%),
    radial-gradient(30% 38% at 86% 14%, rgba(124, 58, 237, .15), transparent 70%),
    radial-gradient(32% 40% at 78% 86%, rgba(219, 39, 119, .12), transparent 70%),
    radial-gradient(30% 36% at 38% 92%, rgba(13, 148, 136, .12), transparent 70%),
    linear-gradient(180deg, #FAFBFF 0%, #FFFFFF 100%);
}
.grad {
  background: linear-gradient(95deg, #1D4ED8 0%, #7C3AED 55%, #DB2777 100%);
  -webkit-background-clip: text; background-clip: text; color: transparent;
  -webkit-box-decoration-break: clone; box-decoration-break: clone;
  white-space: nowrap;   /* 强调短语整体换行，别把「on」单独留在上一行末尾 */
}
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr); gap: 72px; align-items: center; }
.eyebrow { display: inline-flex; align-items: center; gap: 10px; font-size: 15px; font-weight: 600; color: var(--ink-2); }
.eyebrow img { width: 22px; height: 22px; border-radius: 6px; }
.hero h1 { margin-top: 22px; font-size: 68px; line-height: 1.02; letter-spacing: -.045em; }
.lang-zh .hero h1 { font-size: 60px; line-height: 1.14; letter-spacing: -.01em; }
.lead { margin-top: 24px; max-width: 32em; font-size: 19px; color: var(--ink-2); }
.cta-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 36px; }
.cta-row.center { justify-content: center; }
.trust { display: flex; flex-wrap: wrap; gap: 10px 22px; margin-top: 28px; font-size: 14px; color: var(--ink-3); }
.trust li { display: inline-flex; align-items: center; gap: 7px; }
.trust svg { width: 16px; height: 16px; color: var(--accent); }
.trust svg path { stroke-width: 2.2; }
.hero-visual { position: relative; z-index: 0; }
/* 首屏对比图四周的两块真实界面：语言胶囊（同 App 语言条）、自动翻译开关 */
.chip {
  position: absolute; z-index: 4; display: inline-flex; align-items: center; gap: 10px; padding: 8px 16px 8px 10px;
  border-radius: 999px; background: rgba(255, 255, 255, .94); -webkit-backdrop-filter: blur(12px); backdrop-filter: blur(12px);
  box-shadow: 0 0 0 1px rgba(15, 23, 42, .06), 0 18px 40px -16px rgba(15, 23, 42, .4);
  font-size: 15px; font-weight: 600; white-space: nowrap; pointer-events: none;
}
.chip-lang { top: -24px; left: -28px; padding-left: 18px; }
.chip-lang .swap { display: inline-flex; align-items: center; justify-content: center; width: 30px; height: 30px; border-radius: 50%; background: #F1F1EE; color: var(--ink-2); }
.chip-lang .swap svg { width: 16px; height: 16px; }
.chip-auto { right: 32px; bottom: -22px; padding-right: 12px; }
.chip-ico { display: inline-flex; align-items: center; justify-content: center; width: 30px; height: 30px; border-radius: 9px; background: #E6F5EB; color: #16A34A; }
.chip-ico svg { width: 18px; height: 18px; }
.chip .sv-switch { width: 38px; height: 22px; }
.chip .sv-switch::after { top: 3px; right: 3px; width: 16px; height: 16px; }

/* 多语言「你好」滚动带 */
.langs { padding: 8px 0 12px; }
.langs-title { margin-bottom: 18px; text-align: center; font-size: 14px; font-weight: 600; color: var(--ink-3); }
.marquee {
  overflow: hidden;
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 7%, #000 93%, transparent);
  mask-image: linear-gradient(90deg, transparent, #000 7%, #000 93%, transparent);
}
.track { display: flex; width: max-content; animation: marquee 70s linear infinite; }
.marquee:hover .track { animation-play-state: paused; }
.set { display: flex; gap: 12px; padding-right: 12px; }
.g { display: inline-flex; align-items: baseline; gap: 8px; padding: 10px 18px; border-radius: 999px; background: var(--bg); color: var(--fg); white-space: nowrap; }
.g b { font-size: 17px; font-weight: 650; }
.g i { font-size: 13px; font-style: normal; opacity: .72; }
@keyframes marquee { to { transform: translateX(-50%); } }
.langs + .section { padding-top: 112px; }

/* ---------------- 原文 / 译文对比（拖动中间的悬浮球） ---------------- */
.compare {
  --pos: 50%;
  position: relative; margin: 0; overflow: hidden; aspect-ratio: 15 / 16; border-radius: 28px; background: #16162A;
  box-shadow: 0 0 0 1px rgba(15, 23, 42, .06), 0 50px 100px -48px rgba(15, 23, 42, .55);
  touch-action: pan-y; -webkit-user-select: none; user-select: none; cursor: ew-resize; isolation: isolate;
}
.compare img { position: absolute; top: 0; right: 0; bottom: 0; left: 0; width: 100%; height: 100%; object-fit: cover; -webkit-user-drag: none; }
.compare .before { position: absolute; top: 0; right: 0; bottom: 0; left: 0; -webkit-clip-path: inset(0 calc(100% - var(--pos)) 0 0); clip-path: inset(0 calc(100% - var(--pos)) 0 0); }
.compare .divider { position: absolute; top: 0; bottom: 0; left: var(--pos); z-index: 3; width: 0; pointer-events: none; }
.compare .divider::before {
  content: ""; position: absolute; top: 0; bottom: 0; left: -1.5px; width: 3px; background: #fff;
  box-shadow: 0 0 0 1px rgba(0, 0, 0, .06), 0 0 18px rgba(0, 0, 0, .25);
}
.compare .knob {
  position: absolute; top: 50%; left: 0; width: 60px; height: 60px; margin: -30px 0 0 -30px; border-radius: 50%;
  background: var(--accent); display: flex; align-items: center; justify-content: center;
  box-shadow: 0 0 0 5px #fff, 0 14px 30px -8px rgba(0, 0, 0, .55); transition: transform .2s var(--ease);
}
.compare .knob svg { width: 32px; height: 32px; }
.compare .knob::before, .compare .knob::after {   /* 两侧的小箭头，提示可以左右拖 */
  content: ""; position: absolute; top: 50%; width: 8px; height: 8px; margin-top: -4px;
  border: solid #fff; border-width: 0 0 2.5px 2.5px; filter: drop-shadow(0 1px 2px rgba(0, 0, 0, .5));
}
.compare .knob::before { left: -24px; transform: rotate(45deg); }
.compare .knob::after { right: -24px; transform: rotate(-135deg); }
.compare.dragging .knob { transform: scale(1.06); }
.compare .range {   /* 只给键盘和读屏用；拖动由 home.js 的 pointer 事件处理 */
  position: absolute; left: 0; bottom: 0; width: 100%; height: 1px; opacity: 0; pointer-events: none;
}
.compare .range:focus-visible ~ .divider .knob { box-shadow: 0 0 0 5px #fff, 0 0 0 8px var(--accent), 0 14px 30px -8px rgba(0, 0, 0, .55); }
/* 图下方的说明条：左原文语言、中间提示、右译文语言 */
.caption { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 16px; font-size: 13px; color: var(--ink-3); }
.cap-src, .cap-dst { flex: none; padding: 4px 11px; border-radius: 999px; font-weight: 600; background: var(--soft); color: var(--ink-2); }
.cap-dst { background: var(--accent-soft); color: var(--accent); }
.cap-hint { text-align: center; }

/* ---------------- 通用分区 ---------------- */
.section { padding: 128px 0; }
#faq { padding-top: 0; }   /* 紧跟在同为白底的下载区后面 */
.sec-head { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 32px 64px; align-items: end; margin-bottom: 56px; }
.sec-head h2 { font-size: 48px; line-height: 1.06; letter-spacing: -.04em; max-width: 13em; }
.lang-zh .sec-head h2 { font-size: 42px; line-height: 1.2; letter-spacing: -.01em; }
.sec-head p { font-size: 18px; color: var(--ink-2); max-width: 32em; justify-self: end; }
.sec-head:has(h2:only-child) { grid-template-columns: minmax(0, 1fr); }

/* 场景切换：左边标签（选中的带说明），右边对比图 */
.showcase { display: grid; grid-template-columns: minmax(0, 400px) minmax(0, 1fr); gap: 72px; align-items: center; }
.tabs { display: flex; flex-direction: column; }
.tab {
  display: block; width: 100%; padding: 20px 0 20px 26px; text-align: left; background: none; border: 0; cursor: pointer;
  border-left: 2px solid var(--line); transition: border-color .2s var(--ease);
}
.tab-title { display: flex; align-items: center; gap: 12px; font-size: 21px; font-weight: 650; letter-spacing: -.02em; color: #767672; transition: color .2s; }
.tab-dot { flex: none; width: 10px; height: 10px; border-radius: 50%; background: var(--c); opacity: .35; transition: opacity .2s; }
.tab[aria-selected="true"] .tab-dot { opacity: 1; box-shadow: 0 0 0 4px var(--tint); }
.tab:hover .tab-title { color: var(--ink-2); }
.tab-text { display: none; margin-top: 10px; padding-left: 22px; font-size: 16px; line-height: 1.65; color: var(--ink-2); }
.tab[aria-selected="true"] { border-left-color: var(--c); }
.tab[aria-selected="true"] .tab-title { color: var(--ink); }
.tab[aria-selected="true"] .tab-text { display: block; }
.panels { max-width: 620px; width: 100%; justify-self: end; }
.panel { padding: 32px 32px 18px; border-radius: 36px; background: var(--tint); }
.panel[hidden] { display: none; }
.panel .cap-src { background: rgba(255, 255, 255, .7); }
.panel .cap-dst { background: #fff; color: var(--c); }

/* 三步 */
.band { background: linear-gradient(180deg, #F4F6FF 0%, #FAF7FF 100%); }
.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 40px; }
.steps li { position: relative; }
/* 每步一张小图：真实场景图裁切 + 悬浮球 */
.sv {
  position: relative; overflow: hidden; aspect-ratio: 4 / 3; margin-bottom: 28px; border-radius: 18px; background: #fff;
  box-shadow: 0 0 0 1px rgba(15, 23, 42, .06), 0 24px 50px -30px rgba(15, 23, 42, .35);
}
.sv-scene img { position: absolute; top: 0; right: 0; bottom: 0; left: 0; width: 100%; height: 100%; object-fit: cover; }
.mini-ball {
  position: absolute; right: 16px; top: 50%; width: 52px; height: 52px; margin-top: -26px; border-radius: 50%;
  background: var(--accent); display: flex; align-items: center; justify-content: center;
  box-shadow: 0 0 0 4px rgba(255, 255, 255, .9), 0 10px 22px -6px rgba(0, 0, 0, .5);
}
.mini-ball svg { width: 28px; height: 28px; }
.mini-ball.tapped::after { content: ""; position: absolute; inset: -13px; border-radius: 50%; border: 2px solid rgba(255, 255, 255, .85); }
.sv-toggle { display: flex; align-items: center; justify-content: center; padding: 24px; background: linear-gradient(160deg, #EEF2FF 0%, #FFFFFF 70%); }
.sv-card {
  display: flex; align-items: center; gap: 14px; width: 100%; max-width: 330px; padding: 18px; border-radius: 18px; background: #fff;
  box-shadow: 0 0 0 1px rgba(15, 23, 42, .06), 0 16px 36px -20px rgba(15, 23, 42, .35);
}
.sv-card .mini-ball { position: static; flex: none; width: 44px; height: 44px; margin: 0; box-shadow: none; }
.sv-card .mini-ball svg { width: 24px; height: 24px; }
.sv-tt { flex: 1; min-width: 0; }
.sv-tt b { display: block; font-size: 16px; font-weight: 650; }
.sv-tt span { display: block; margin-top: 2px; font-size: 13px; line-height: 1.4; color: var(--ink-3); }
.sv-switch { position: relative; flex: none; width: 46px; height: 28px; border-radius: 999px; background: var(--accent); }
.sv-switch::after { content: ""; position: absolute; top: 3px; right: 3px; width: 22px; height: 22px; border-radius: 50%; background: #fff; box-shadow: 0 1px 3px rgba(0, 0, 0, .3); }
.step {
  display: inline-flex; align-items: center; justify-content: center; width: 34px; height: 34px; border-radius: 50%;
  background: linear-gradient(135deg, #2563EB, #7C3AED); color: #fff; font-size: 15px; font-weight: 600;
}
.steps h3 { margin-top: 16px; font-size: 22px; letter-spacing: -.02em; line-height: 1.3; }
.steps p { margin-top: 10px; color: var(--ink-2); }

/* 功能：细线网格 */
.feats {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1px; overflow: hidden;
  background: var(--line); border: 1px solid var(--line); border-radius: 24px;
}
.feats li { padding: 36px 32px 34px; background: #fff; }
.fi-tile { display: inline-flex; align-items: center; justify-content: center; width: 48px; height: 48px; border-radius: 14px; }
.fi-tile svg { width: 26px; height: 26px; }
.feats h3 { margin-top: 20px; font-size: 19px; letter-spacing: -.015em; line-height: 1.35; }
.feats p { margin-top: 8px; font-size: 15px; color: var(--ink-2); }
.modes-note { margin-top: 24px; font-size: 15px; color: var(--ink-3); }

/* 品牌蓝数据带（同宣传图、商店截图首张的深蓝渐变） */
.brandband { position: relative; isolation: isolate; overflow: hidden; color: #fff;
             background: linear-gradient(165deg, #2152E0 0%, #1D4ED8 50%, #1A3FB8 100%); }
.brandband::before {
  content: ""; position: absolute; inset: 0; z-index: -1; pointer-events: none;
  background: radial-gradient(45% 60% at 90% 0%, rgba(255, 255, 255, .16), transparent 70%),
              radial-gradient(40% 60% at 0% 100%, rgba(96, 165, 250, .35), transparent 70%);
}
.brandband .sec-head h2 { color: #fff; }
.tech { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 48px; }
.tech li { padding-top: 28px; border-top: 1px solid rgba(255, 255, 255, .24); }
.tech b { display: block; font-size: 76px; line-height: 1; font-weight: 700; letter-spacing: -.05em; }
.lang-zh .tech b { letter-spacing: -.02em; }
.tech-label { display: block; margin-top: 14px; font-size: 18px; font-weight: 600; color: #BFDBFE; }
.tech p { margin-top: 10px; font-size: 16px; color: rgba(255, 255, 255, .8); }

/* 下载：列表 */
.stores { border-top: 1px solid var(--line); }
.store { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 26px 4px; border-bottom: 1px solid var(--line); }
.store h3 { display: flex; align-items: center; flex-wrap: wrap; gap: 10px; font-size: 19px; letter-spacing: -.015em; }
.store p { margin-top: 4px; font-size: 15px; color: var(--ink-3); }
.rec { padding: 2px 9px; border-radius: 999px; background: var(--accent-soft); color: var(--accent); font-size: 12px; font-weight: 600; letter-spacing: 0; }
.store-btn {
  flex: none; display: inline-flex; align-items: center; gap: 8px; height: 44px; padding: 0 20px; border-radius: 999px;
  font-size: 15px; font-weight: 600; box-shadow: inset 0 0 0 1px #D8D8D3; transition: background-color .2s var(--ease);
}
.store-btn svg { width: 16px; height: 16px; }
.store-btn:hover { background: var(--soft); }
.store.is-rec .store-btn { background: var(--ink); color: #fff; box-shadow: none; }
.store.is-rec .store-btn:hover { background: #2A2A2E; }

/* 下载 / 常见问题：左标题（桌面端跟随滚动），右内容 */
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.7fr); gap: 72px; align-items: start; }
.split-head { position: sticky; top: 108px; }
.split-head h2 { font-size: 48px; line-height: 1.06; letter-spacing: -.04em; }
.lang-zh .split-head h2 { font-size: 42px; line-height: 1.2; letter-spacing: -.01em; }
.split-head p { margin-top: 20px; font-size: 17px; color: var(--ink-2); }
.split-head .dl-tip { margin-top: 14px; font-size: 14px; color: var(--ink-3); }
.link { display: inline-flex; align-items: center; gap: 8px; margin-top: 6px; color: var(--accent); font-weight: 600; }
.link svg { width: 18px; height: 18px; }
.link:hover { text-decoration: underline; text-underline-offset: 3px; }
.faq { border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary {
  position: relative; padding: 26px 48px 26px 0; list-style: none; cursor: pointer;
  font-size: 18px; font-weight: 600; letter-spacing: -.01em;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::before, .faq summary::after {   /* 加号 / 减号 */
  content: ""; position: absolute; right: 6px; top: 50%; width: 14px; height: 2px; margin-top: -1px;
  background: var(--ink-2); border-radius: 2px; transition: transform .25s var(--ease);
}
.faq summary::after { transform: rotate(90deg); }
.faq details[open] summary::after { transform: rotate(0deg); }
.faq details p { padding: 0 48px 26px 0; font-size: 16px; color: var(--ink-2); }

/* 结尾号召：柔和彩色渐变卡片 */
.end { padding: 24px 0 120px; text-align: center; }
.end-card {
  position: relative; isolation: isolate; overflow: hidden; padding: 88px 32px 96px; border-radius: 40px;
  background:
    radial-gradient(40% 70% at 10% 10%, rgba(37, 99, 235, .20), transparent 70%),
    radial-gradient(40% 70% at 90% 20%, rgba(124, 58, 237, .18), transparent 70%),
    radial-gradient(45% 70% at 70% 100%, rgba(219, 39, 119, .14), transparent 70%),
    radial-gradient(40% 60% at 20% 100%, rgba(13, 148, 136, .14), transparent 70%),
    #F8F9FF;
}
.end-icon { width: 72px; height: 72px; margin: 0 auto 28px; border-radius: 18px; box-shadow: 0 18px 36px -14px rgba(29, 78, 216, .5); }
.end h2 { font-size: 56px; line-height: 1.05; letter-spacing: -.045em; }
.lang-zh .end h2 { font-size: 48px; letter-spacing: -.01em; }
.end p { margin-top: 16px; font-size: 18px; color: var(--ink-2); }

/* 页脚 */
.footer { padding: 64px 0 40px; border-top: 1px solid var(--line); }
.footer-grid { display: grid; grid-template-columns: minmax(0, 2fr) repeat(2, minmax(0, 1fr)); gap: 48px; }
.fbrand p { margin: 12px 0 18px; font-size: 15px; color: var(--ink-3); }
.fbrand .lang { margin-left: -8px; }
.fcol h4 { font-size: 14px; font-weight: 600; }
.fcol li { margin-top: 12px; }
.fcol a { font-size: 15px; color: var(--ink-3); transition: color .15s; }
.fcol a:hover { color: var(--ink); }
.legal { margin-top: 56px; font-size: 13px; color: var(--ink-3); }
.legal a:hover { color: var(--ink); }
.legal .sep { margin: 0 10px; }

/* ---------------- 响应式 ---------------- */
@media (max-width: 1080px) {
  .hero-grid { gap: 48px; }
  .hero h1 { font-size: 56px; }
  .lang-zh .hero h1 { font-size: 50px; }
  .showcase { gap: 48px; grid-template-columns: minmax(0, 340px) minmax(0, 1fr); }
}
@media (max-width: 900px) {
  :root { --gutter: 24px; }
  .nav-links { display: none; }
  .hero { padding: 40px 0 96px; }
  .hero-grid { grid-template-columns: minmax(0, 1fr); }
  .hero-visual { width: 100%; max-width: 560px; margin: 12px auto 0; }
  .chip-lang { left: 14px; }
  .chip-auto { right: 20px; }
  .section { padding: 96px 0; }
  #faq { padding-top: 0; }
  .sec-head { grid-template-columns: minmax(0, 1fr); gap: 16px; margin-bottom: 40px; }
  .sec-head p { justify-self: start; }
  .showcase { grid-template-columns: minmax(0, 1fr); gap: 32px; }
  .panels { justify-self: start; }
  .tech { grid-template-columns: minmax(0, 1fr); gap: 36px; }
  .steps { gap: 20px; }
  .steps h3 { font-size: 19px; }
  .steps p { font-size: 15px; }
  .sv-toggle { padding: 12px; }
  .sv-card { gap: 10px; padding: 12px; border-radius: 14px; }
  .sv-card .mini-ball { width: 34px; height: 34px; }
  .sv-card .mini-ball svg { width: 20px; height: 20px; }
  .sv-tt span { display: none; }
  .sv-switch { width: 38px; height: 22px; }
  .sv-switch::after { width: 16px; height: 16px; }
  .mini-ball { width: 40px; height: 40px; margin-top: -20px; right: 10px; }
  .mini-ball svg { width: 22px; height: 22px; }
  .feats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .split { grid-template-columns: minmax(0, 1fr); gap: 32px; }
  .split-head { position: static; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .fbrand { grid-column: 1 / -1; }
  .end { padding: 104px 0 112px; }
}
@media (max-width: 600px) {
  :root { --gutter: 20px; }
  .nav-row { gap: 12px; height: 60px; }
  .nav-end { gap: 6px; }
  .hero { padding-top: 28px; }
  .hero h1 { font-size: 42px; letter-spacing: -.04em; }
  .lang-zh .hero h1 { font-size: 38px; }
  .lead { font-size: 17px; }
  .cta-row .btn { flex: 1 1 100%; }
  .section { padding: 80px 0; }
  #faq { padding-top: 0; }
  .steps { grid-template-columns: minmax(0, 1fr); gap: 40px; }
  .steps h3 { font-size: 20px; }
  .sv-toggle { padding: 20px; }
  .sv-card { gap: 12px; padding: 16px; }
  .sv-tt span { display: block; }
  .sec-head h2, .split-head h2 { font-size: 34px; }
  .lang-zh .sec-head h2, .lang-zh .split-head h2 { font-size: 30px; }
  .sec-head p { font-size: 16px; }
  .compare { border-radius: 20px; }
  .chip { font-size: 13px; padding: 6px 12px 6px 8px; gap: 8px; }
  .chip-lang { top: -18px; left: 10px; padding-left: 12px; }
  .chip-auto { right: 12px; bottom: -18px; }
  .panel { padding: 16px 16px 8px; border-radius: 26px; }
  .end-card { padding: 64px 20px 72px; border-radius: 28px; }
  .g b { font-size: 15px; }
  .compare .knob { width: 52px; height: 52px; margin: -26px 0 0 -26px; }
  .compare .knob svg { width: 28px; height: 28px; }
  .tab { padding: 16px 0 16px 20px; }
  .tab-title { font-size: 18px; }
  .feats { grid-template-columns: minmax(0, 1fr); border-radius: 20px; }
  .feats li { padding: 28px 24px; }
  .tech b { font-size: 60px; }
  .store { flex-wrap: wrap; gap: 14px; }
  .store-info { flex: 1 1 100%; }
  .end h2 { font-size: 38px; }
  .lang-zh .end h2 { font-size: 34px; }
  .footer-grid { gap: 36px; }
}
@media (max-width: 440px) {
  .nav .btn-sm { display: none; }   /* 首屏就有大按钮，窄屏顶栏只留品牌和语言 */
}
@media (max-width: 340px) {
  .brand span { display: none; }
}
@supports not (aspect-ratio: 1 / 1) {
  .compare::before { content: ""; display: block; padding-top: 106.67%; }
  .sv::before { content: ""; display: block; padding-top: 75%; }
  .sv-toggle .sv-card { position: absolute; top: 50%; left: 50%; width: 80%; transform: translate(-50%, -50%); }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}