/* 闪电扫描官网样式：系统字体、无外部依赖；浅色内容区 + 深色主视觉，支持深色模式 */
:root {
  --blue: #1c66fc;
  --blue-strong: #1453d4;
  --blue-soft: #eaf1ff;
  --yellow: #ffd43b;
  --navy-0: #060a16;
  --navy-1: #0c1836;
  --navy-2: #13244a;
  --bg: #ffffff;
  --bg-soft: #f4f7fd;
  --card: #ffffff;
  --ink: #0f172a;
  --muted: #566079;
  --line: #e3e8f2;
  --green: #18a058;
  --radius: 20px;
  --shadow: 0 10px 30px rgba(15, 23, 42, .08);
  --container: 1120px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0a0f1d;
    --bg-soft: #0e1527;
    --card: #121a30;
    --ink: #e8edf7;
    --muted: #9aa6c0;
    --line: #1f2a45;
    --blue-soft: #14244a;
    --shadow: 0 10px 30px rgba(0, 0, 0, .35);
    color-scheme: dark;
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 76px; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.7 -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
:lang(ja) body, body:lang(ja) { font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, "Noto Sans CJK JP", sans-serif; }
:lang(en) body, body:lang(en) { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif; }
img, video { max-width: 100%; height: auto; display: block; }
a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3 { line-height: 1.25; margin: 0; letter-spacing: -.01em; }
p { margin: 0; }
ul, ol { margin: 0; padding: 0; }
:focus-visible { outline: 3px solid var(--yellow); outline-offset: 3px; border-radius: 6px; }
.container { width: min(var(--container), 100% - 40px); margin-inline: auto; }
.skip { position: absolute; left: -999px; top: 8px; background: var(--yellow); color: #000; padding: 8px 14px; border-radius: 8px; z-index: 100; }
.skip:focus { left: 12px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.icon { width: 24px; height: 24px; flex: none; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

/* ---------------- 按钮 ---------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  border-radius: 999px; font-weight: 600; text-decoration: none; white-space: nowrap;
  transition: transform .15s ease, background-color .15s ease, box-shadow .15s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary { background: var(--blue); color: #fff; box-shadow: 0 8px 24px rgba(28, 102, 252, .35); }
.btn-primary:hover { background: var(--blue-strong); }
.btn-ghost { color: #fff; background: rgba(255, 255, 255, .08); border: 1px solid rgba(255, 255, 255, .22); }
.btn-ghost:hover { background: rgba(255, 255, 255, .14); }
.btn-lg { padding: 14px 26px; font-size: 17px; }
.btn-sm { padding: 8px 16px; font-size: 14px; }

/* ---------------- 顶栏 ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(6, 10, 22, .78);
  -webkit-backdrop-filter: saturate(160%) blur(16px);
  backdrop-filter: saturate(160%) blur(16px);
  border-bottom: 1px solid rgba(255, 255, 255, .08);
  color: #fff;
}
.nav { display: flex; align-items: center; gap: 24px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; color: #fff; font-weight: 700; font-size: 18px; white-space: nowrap; flex: none; }
.brand:hover { text-decoration: none; }
.brand img { width: 32px; height: 32px; border-radius: 8px; }
.nav-links { display: flex; gap: 22px; list-style: none; margin-left: 12px; }
.nav-links a { color: rgba(255, 255, 255, .78); font-size: 15px; }
.nav-links a:hover, .nav-links a[aria-current] { color: #fff; text-decoration: none; }
.nav-actions { margin-left: auto; display: flex; align-items: center; gap: 14px; }
.lang { display: flex; gap: 2px; background: rgba(255, 255, 255, .08); border-radius: 999px; padding: 3px; }
.lang a { color: rgba(255, 255, 255, .7); font-size: 13px; padding: 3px 10px; border-radius: 999px; white-space: nowrap; }
.lang .short { display: none; }
.lang a:hover { text-decoration: none; color: #fff; }
.lang a[aria-current] { background: rgba(255, 255, 255, .16); color: #fff; }
.menu-toggle { display: none; background: none; border: 0; color: #fff; padding: 8px; margin-right: -8px; cursor: pointer; }
.menu-toggle .icon { width: 26px; height: 26px; }

/* ---------------- 主视觉 ---------------- */
.hero {
  position: relative; overflow: hidden; color: #fff;
  background:
    radial-gradient(900px 520px at 78% 55%, rgba(28, 102, 252, .45), transparent 70%),
    radial-gradient(1px 1px at 20px 20px, rgba(255, 255, 255, .14) 1px, transparent 0) 0 0 / 40px 40px,
    linear-gradient(180deg, var(--navy-0), var(--navy-1));
}
.hero-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 48px; align-items: center; padding: 72px 0 96px; }
.eyebrow { display: inline-block; font-size: 14px; font-weight: 600; color: #b9cdff; background: rgba(28, 102, 252, .18); border: 1px solid rgba(120, 160, 255, .3); padding: 5px 14px; border-radius: 999px; margin-bottom: 22px; }
.hero h1 { font-size: clamp(40px, 6vw, 68px); font-weight: 800; }
.hero h1 .brand-line { display: block; font-size: .5em; font-weight: 700; color: #cfdcff; margin-bottom: 10px; letter-spacing: .02em; }
.hero h1 em { font-style: normal; color: var(--yellow); white-space: nowrap; }
.lead { font-size: 18px; color: rgba(232, 238, 252, .82); margin: 22px 0 32px; max-width: 34em; }
.cta-row { display: flex; flex-wrap: wrap; gap: 14px; }
.trust { list-style: none; display: flex; flex-wrap: wrap; gap: 10px 22px; margin-top: 28px; color: rgba(232, 238, 252, .78); font-size: 14px; }
.trust li { display: flex; align-items: center; gap: 6px; }
.trust .icon { width: 18px; height: 18px; color: #6cf0a4; stroke-width: 2.4; }
.hero-visual { position: relative; display: flex; justify-content: center; }
.hero-visual .phone { width: min(320px, 72vw); filter: drop-shadow(0 30px 60px rgba(0, 0, 0, .55)); }
.float-card {
  position: absolute; display: flex; align-items: center; gap: 8px;
  padding: 10px 16px; border-radius: 14px; font-size: 14px; font-weight: 600; color: #fff;
  background: rgba(17, 30, 64, .72); border: 1px solid rgba(255, 255, 255, .16);
  -webkit-backdrop-filter: blur(12px); backdrop-filter: blur(12px);
  box-shadow: 0 12px 30px rgba(0, 0, 0, .35);
  animation: float 6s ease-in-out infinite;
}
.float-card .icon { width: 20px; height: 20px; color: #6cf0a4; stroke-width: 2.4; }
.fc-1 { top: 18%; left: 2%; }
.fc-2 { bottom: 16%; right: 0; animation-delay: -3s; }
@keyframes float { 50% { transform: translateY(-10px); } }
@media (prefers-reduced-motion: reduce) { .float-card { animation: none; } html { scroll-behavior: auto; } }

/* ---------------- 通用分区 ---------------- */
.section { padding: 96px 0; }
.section.soft { background: var(--bg-soft); }
.section-head { text-align: center; max-width: 760px; margin: 0 auto 48px; }
.section-head h2 { font-size: clamp(28px, 3.6vw, 40px); font-weight: 800; }
.section-head p { color: var(--muted); font-size: 17px; margin-top: 14px; }

/* 前后对比 */
.compare-wrap { display: grid; grid-template-columns: 1fr 1.25fr; gap: 28px; align-items: center; max-width: 920px; margin: 0 auto; }
.compare-wrap figure { margin: 0; }
.compare-wrap figcaption { text-align: center; color: var(--muted); font-size: 14px; margin-top: 10px; }
.photo-desk img { border-radius: 16px; box-shadow: var(--shadow); }
.ba { position: relative; border-radius: 16px; overflow: hidden; box-shadow: var(--shadow); --pos: 50%; touch-action: pan-y; }
.ba img { width: 100%; }
.ba .ba-after { position: absolute; inset: 0; height: 100%; object-fit: cover; clip-path: inset(0 0 0 var(--pos)); }
.ba::after { content: ""; position: absolute; top: 0; bottom: 0; left: var(--pos); width: 3px; margin-left: -1.5px; background: #fff; box-shadow: 0 0 0 1px rgba(0, 0, 0, .15); pointer-events: none; }
.ba input[type=range] { position: absolute; inset: 0; width: 100%; height: 100%; margin: 0; opacity: 0; cursor: ew-resize; }
.ba-handle { position: absolute; top: 50%; left: var(--pos); width: 44px; height: 44px; margin: -22px 0 0 -22px; border-radius: 50%; background: #fff; color: var(--blue); display: grid; place-items: center; box-shadow: 0 6px 18px rgba(0, 0, 0, .25); pointer-events: none; }
.ba-label { position: absolute; top: 14px; font-size: 13px; font-weight: 600; color: #fff; background: rgba(6, 10, 22, .62); padding: 4px 12px; border-radius: 999px; pointer-events: none; }
.ba-label.l { left: 14px; }
.ba-label.r { right: 14px; background: var(--blue); }

/* 功能宫格 */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; box-shadow: 0 1px 0 rgba(15, 23, 42, .02); transition: transform .2s ease, box-shadow .2s ease; }
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.card h3 { font-size: 19px; margin: 16px 0 8px; }
.card p { color: var(--muted); font-size: 15px; }
.card-icon { width: 46px; height: 46px; border-radius: 14px; display: grid; place-items: center; background: var(--blue-soft); color: var(--blue); }

/* 功能详解 */
.feature-row { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; padding: 56px 0; }
.feature-row + .feature-row { border-top: 1px solid var(--line); }
.feature-row:nth-child(even) .feature-media { order: -1; }
.feature-media { display: flex; justify-content: center; gap: 18px; position: relative; }
.feature-media .phone { width: min(280px, 64vw); filter: drop-shadow(0 24px 40px rgba(15, 23, 42, .22)); }
.feature-copy .tag { display: inline-block; font-size: 13px; font-weight: 700; color: var(--blue); background: var(--blue-soft); padding: 4px 12px; border-radius: 999px; }
.feature-copy h3 { font-size: clamp(26px, 3vw, 34px); font-weight: 800; margin: 14px 0 14px; }
.feature-copy p { color: var(--muted); font-size: 17px; }
.checks { list-style: none; margin: 20px 0 0; display: grid; gap: 10px; }
.checks li { display: flex; gap: 10px; align-items: flex-start; }
.checks .icon { width: 20px; height: 20px; color: var(--green); stroke-width: 2.4; margin-top: 4px; }
.more { display: inline-flex; align-items: center; gap: 6px; margin-top: 22px; font-weight: 600; }
.crop-pair { display: grid; grid-template-columns: 1fr; gap: 14px; margin-top: 24px; }
.crop-pair figure { margin: 0; }
.crop-pair img { border-radius: 12px; border: 1px solid var(--line); }
.crop-pair figcaption { font-size: 13px; color: var(--muted); margin-top: 6px; }

/* 隐私 */
.privacy { color: #fff; background: radial-gradient(700px 400px at 15% 20%, rgba(28, 102, 252, .35), transparent 70%), linear-gradient(180deg, var(--navy-1), var(--navy-0)); }
.privacy .section-head p { color: rgba(232, 238, 252, .78); }
.privacy-points { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.privacy-points .card { background: rgba(255, 255, 255, .06); border-color: rgba(255, 255, 255, .12); color: #fff; }
.privacy-points .card p { color: rgba(232, 238, 252, .75); }
.privacy-points .card-icon { background: rgba(108, 240, 164, .14); color: #6cf0a4; }
.privacy-note { max-width: 760px; margin: 36px auto 0; text-align: center; color: rgba(232, 238, 252, .72); font-size: 15px; }
.privacy-note a { color: #9cc0ff; }
.privacy-tip { max-width: 760px; margin: 14px auto 0; text-align: center; color: rgba(232, 238, 252, .6); font-size: 14px; }

/* 视频（成片自带手机样机，这里只用圆角卡片） */
.video-frame { width: min(360px, 86vw); margin: 0 auto; border-radius: 24px; overflow: hidden; box-shadow: 0 30px 60px rgba(15, 23, 42, .28); background: var(--navy-0); }
.video-frame video { width: 100%; aspect-ratio: 9 / 16; background: var(--navy-0); }

/* 场景 */
.cases { display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; }
.cases .card { padding: 22px; }
.cases h3 { margin-top: 0; font-size: 18px; }

/* 教程卡片 */
.guide-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 18px; }
.guide-card { display: flex; gap: 16px; align-items: center; color: var(--ink); }
.guide-card:hover { text-decoration: none; }
.guide-card img { width: 74px; border-radius: 12px; flex: none; }
.guide-card h3 { font-size: 17px; margin: 0 0 4px; }
.guide-card p { font-size: 14px; color: var(--muted); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

/* 常见问题 */
.faq { max-width: 820px; margin: 0 auto; display: grid; gap: 12px; }
.faq details { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 0 22px; }
.faq summary { cursor: pointer; list-style: none; padding: 18px 0; font-weight: 700; font-size: 17px; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-size: 22px; line-height: 1; color: var(--blue); transition: transform .2s ease; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details > div { padding: 0 0 20px; color: var(--muted); }

/* 号召 */
.cta-band { text-align: center; color: #fff; background: linear-gradient(135deg, #1c66fc, #3b2fd6); padding: 80px 0; }
.cta-band h2 { font-size: clamp(28px, 4vw, 42px); font-weight: 800; }
.cta-band p { color: rgba(255, 255, 255, .85); margin: 12px 0 28px; font-size: 18px; }
.cta-band .btn-primary { background: #fff; color: var(--blue); box-shadow: 0 10px 30px rgba(0, 0, 0, .2); }

/* 页脚 */
.site-footer { background: var(--navy-0); color: rgba(232, 238, 252, .72); padding: 56px 0 28px; font-size: 14px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 32px; }
.site-footer h2 { font-size: 15px; color: #fff; margin-bottom: 14px; }
.site-footer ul { list-style: none; display: grid; gap: 8px; }
.site-footer a { color: rgba(232, 238, 252, .72); }
.site-footer a:hover { color: #fff; }
.footer-brand p { margin-top: 12px; max-width: 26em; }
.footer-bottom { border-top: 1px solid rgba(255, 255, 255, .08); margin-top: 40px; padding-top: 22px; display: flex; flex-wrap: wrap; gap: 8px 20px; justify-content: space-between; }
.footer-bottom .beian { display: flex; flex-wrap: wrap; gap: 6px 18px; }

/* ---------------- 内页（教程 / 帮助） ---------------- */
.page-hero { color: #fff; background: radial-gradient(700px 300px at 85% 0%, rgba(28, 102, 252, .4), transparent 70%), linear-gradient(180deg, var(--navy-0), var(--navy-1)); padding: 40px 0 56px; }
.page-hero h1 { font-size: clamp(28px, 4.2vw, 44px); font-weight: 800; max-width: 22em; }
.page-hero .lead { margin: 16px 0 0; max-width: 40em; }
.breadcrumb { font-size: 14px; color: rgba(232, 238, 252, .65); margin-bottom: 18px; }
.breadcrumb ol { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; }
.breadcrumb li + li::before { content: "›"; margin-right: 6px; }
.breadcrumb a { color: rgba(232, 238, 252, .82); }
.meta { margin-top: 14px; font-size: 14px; color: rgba(232, 238, 252, .6); }
.article-layout { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 56px; padding: 56px 0 80px; }
.prose h2 { font-size: 26px; font-weight: 800; margin: 44px 0 18px; }
.prose h2:first-child { margin-top: 0; }
.prose p { margin: 0 0 16px; }
.prose ul { padding-left: 1.2em; display: grid; gap: 8px; }
.steps { list-style: none; counter-reset: step; display: grid; gap: 18px; padding: 0 !important; }
.steps li { counter-increment: step; position: relative; padding: 20px 22px 20px 72px; background: var(--card); border: 1px solid var(--line); border-radius: 16px; }
.steps li::before { content: counter(step); position: absolute; left: 22px; top: 20px; width: 34px; height: 34px; border-radius: 50%; background: var(--blue); color: #fff; font-weight: 800; display: grid; place-items: center; }
.steps h3 { font-size: 18px; margin-bottom: 6px; }
.steps p { margin: 0; color: var(--muted); }
.figure-row { display: flex; flex-wrap: wrap; gap: 24px; justify-content: center; margin: 28px 0; }
.figure-row figure { margin: 0; width: min(240px, 70vw); }
.figure-row figcaption { text-align: center; font-size: 13px; color: var(--muted); margin-top: 8px; }
.aside-card { position: sticky; top: 90px; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; box-shadow: var(--shadow); text-align: center; }
.aside-card img { width: 64px; border-radius: 14px; margin: 0 auto 12px; }
.aside-card h2 { font-size: 20px; }
.aside-card p { color: var(--muted); font-size: 14px; margin: 8px 0 18px; }
.aside-card ul { list-style: none; text-align: left; margin-top: 22px; border-top: 1px solid var(--line); padding-top: 18px; display: grid; gap: 10px; font-size: 14px; }
.note { border-left: 4px solid var(--blue); background: var(--blue-soft); padding: 14px 18px; border-radius: 0 12px 12px 0; color: var(--ink); }
.support-sections { padding: 56px 0 88px; display: grid; gap: 56px; }
.support-sections h2 { font-size: 28px; font-weight: 800; margin-bottom: 20px; }
.support-sections .faq { max-width: none; margin: 0; }
.contact-card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px; }
.contact-card .mail { font-size: 22px; font-weight: 700; display: inline-block; margin: 8px 0 12px; }
.links-list { list-style: none; display: flex; flex-wrap: wrap; gap: 12px; }
.links-list a { display: inline-block; padding: 10px 18px; border: 1px solid var(--line); border-radius: 999px; color: var(--ink); }
.links-list a:hover { border-color: var(--blue); color: var(--blue); text-decoration: none; }

/* ---------------- 响应式 ---------------- */
@media (max-width: 960px) {
  .hero-grid, .feature-row, .compare-wrap, .article-layout { grid-template-columns: 1fr; }
  .hero-grid { padding: 48px 0 72px; gap: 40px; text-align: center; }
  .hero .lead { margin-inline: auto; }
  .cta-row, .trust { justify-content: center; }
  .feature-row { gap: 32px; padding: 44px 0; }
  .feature-row:nth-child(even) .feature-media { order: 0; }
  .grid-3, .privacy-points { grid-template-columns: 1fr 1fr; }
  .cases { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .aside-card { position: static; }
  .nav-links { display: none; position: absolute; top: 64px; left: 0; right: 0; flex-direction: column; gap: 0; margin: 0; background: rgba(6, 10, 22, .96); padding: 8px 20px 16px; border-bottom: 1px solid rgba(255, 255, 255, .08); }
  .nav-links a { display: block; padding: 12px 0; font-size: 16px; }
  .nav-open .nav-links { display: flex; }
  .menu-toggle { display: block; }
  .nav-actions .btn { display: none; }
}
@media (max-width: 640px) {
  .section { padding: 68px 0; }
  .grid-3, .privacy-points, .cases, .footer-grid { grid-template-columns: 1fr; }
  .lang a { padding: 3px 9px; }
  .lang .full { display: none; }
  .lang .short { display: inline; }
  .nav { gap: 12px; }
  .float-card { font-size: 12px; padding: 8px 12px; }
  .fc-1 { left: -4px; } .fc-2 { right: -4px; }
  .steps li { padding-left: 64px; }
}