/* ============================================================
   闪回官网 · 样式
   风格：白底分节、浅灰交替、蓝紫渐变主色、琥珀点缀、
        圆角卡片 + 柔和阴影、滚动渐显、跑马灯、数字滚动。
   零依赖：不用框架、不用图标库，图标全是内联 SVG。
   ============================================================ */

:root {
  --ink: #0f172a;
  --ink-2: #334155;
  --ink-3: #64748b;
  --line: #e2e8f0;
  --bg: #ffffff;
  --bg-alt: #f6f8fc;
  --bg-sunken: #eef2f8;

  --brand: #2f6fe0;
  --brand-2: #8b5cf6;
  --brand-3: #c084fc;
  --amber: #f59e0b;
  --green: #16a34a;

  --grad: linear-gradient(135deg, var(--brand) 0%, var(--brand-2) 100%);
  --grad-soft: linear-gradient(135deg, #e8efff 0%, #f3ecff 100%);

  --r-sm: 10px;
  --r: 16px;
  --r-lg: 24px;
  --shadow: 0 1px 2px rgba(15, 23, 42, .04), 0 10px 30px -12px rgba(15, 23, 42, .12);
  --shadow-lg: 0 2px 6px rgba(15, 23, 42, .06), 0 30px 60px -24px rgba(47, 111, 224, .28);

  --container: 1180px;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4 { margin: 0; line-height: 1.25; letter-spacing: -.01em; }
p { margin: 0; }

.container { width: min(var(--container), 100% - 48px); margin: 0 auto; }

.gradient-text {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ---------------- 按钮 ---------------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 11px 20px; border-radius: 12px;
  font-weight: 600; font-size: 15px; line-height: 1;
  border: 1px solid transparent; cursor: pointer;
  transition: transform .18s var(--ease), box-shadow .18s var(--ease), background .18s, color .18s, border-color .18s;
  white-space: nowrap;
}
.btn-lg { padding: 15px 26px; font-size: 16px; border-radius: 14px; }
.btn-primary {
  color: #fff; background: var(--grad);
  box-shadow: 0 8px 20px -8px rgba(47, 111, 224, .6);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 28px -10px rgba(47, 111, 224, .65); }
.btn-primary:active { transform: translateY(0); }
.btn-outline { color: var(--brand); background: #fff; border-color: #cfdcf7; }
.btn-outline:hover { background: #f0f5ff; border-color: var(--brand); transform: translateY(-2px); }
.btn-ghost { color: var(--ink-2); background: transparent; }
.btn-ghost:hover { background: var(--bg-sunken); }
.btn-light { color: var(--brand); background: #fff; }
.btn-light:hover { transform: translateY(-2px); box-shadow: 0 14px 28px -12px rgba(0,0,0,.35); }
.btn-outline-light { color: #fff; border-color: rgba(255,255,255,.55); }
.btn-outline-light:hover { background: rgba(255,255,255,.12); }

/* ---------------- 顶栏 ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.82);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s, box-shadow .2s;
}
.site-header.scrolled { border-bottom-color: var(--line); box-shadow: 0 6px 20px -16px rgba(15,23,42,.25); }
.header-inner { display: flex; align-items: center; gap: 28px; height: 68px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; }
.brand-mark { display: inline-flex; }
.brand-mark img { border-radius: 8px; display: block; }
.nav { display: flex; gap: 4px; margin-left: 12px; }
.nav a { padding: 8px 12px; border-radius: 10px; color: var(--ink-2); font-size: 15px; transition: background .15s, color .15s; }
.nav a:hover, .nav a.active { color: var(--brand); background: #eef3ff; }
.header-cta { margin-left: auto; display: flex; gap: 8px; }
.nav-toggle { display: none; margin-left: auto; width: 42px; height: 42px; border: 0; background: transparent; border-radius: 10px; cursor: pointer; flex-direction: column; justify-content: center; align-items: center; gap: 5px; }
.nav-toggle span { width: 20px; height: 2px; background: var(--ink); border-radius: 2px; transition: transform .2s, opacity .2s; }

/* ---------------- 首屏 ---------------- */
.hero { position: relative; padding: 88px 0 72px; overflow: hidden; }
.hero-bg { position: absolute; inset: 0; pointer-events: none; }
.glow { position: absolute; border-radius: 50%; filter: blur(70px); opacity: .55; animation: drift 14s ease-in-out infinite alternate; }
.glow-a { width: 560px; height: 560px; left: -160px; top: -140px; background: #c7d7ff; }
.glow-b { width: 520px; height: 520px; right: -120px; top: 40px; background: #e6d8ff; animation-delay: -5s; }
.glow-c { width: 360px; height: 360px; left: 46%; bottom: -200px; background: #ffe9c2; opacity: .45; animation-delay: -9s; }
@keyframes drift { from { transform: translate3d(0,0,0) scale(1); } to { transform: translate3d(30px, 24px, 0) scale(1.06); } }

.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 56px; align-items: center; position: relative; }
.hero h1 { font-size: clamp(36px, 5vw, 58px); font-weight: 800; margin: 0 0 18px; }
.lead { font-size: 18px; color: var(--ink-2); max-width: 540px; }
.hero-tagline { font-size: clamp(22px, 2.6vw, 30px); font-weight: 800; color: var(--ink); margin-top: 6px; }
.hero-claim { font-size: 17px; font-weight: 600; color: var(--ink-2); margin-top: 8px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 28px; }
.hero-media { position: relative; }
.video-frame {
  position: relative; border-radius: var(--r-lg); background: #0f172a;
  box-shadow: var(--shadow-lg); overflow: hidden;
  transform: perspective(1200px) rotateY(-6deg) rotateX(2deg);
  transition: transform .6s var(--ease);
}
.hero-media:hover .video-frame { transform: perspective(1200px) rotateY(0) rotateX(0); }
.video-img { display: block; width: 100%; height: auto; }

/* 占位标记：后期替换时一眼能找到 */
.ph-label {
  position: absolute; left: 12px; bottom: 10px; z-index: 2;
  padding: 3px 8px; border-radius: 6px; font-size: 11px; letter-spacing: .06em;
  color: #fff; background: rgba(245, 158, 11, .92);
}

.float-card {
  position: absolute; padding: 10px 14px; border-radius: 14px; background: #fff;
  box-shadow: var(--shadow-lg); font-size: 13px; font-weight: 600; display: flex; align-items: center; gap: 8px;
  animation: floaty 6s ease-in-out infinite;
}
.float-card em { font-style: normal; font-weight: 500; color: var(--amber); font-size: 11px; }
.fc-1 { left: -28px; bottom: 34px; }
.fc-2 { right: -20px; top: 28px; animation-delay: -3s; }
.fc-2 b { font-size: 18px; color: var(--brand); }
.fc-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--green); box-shadow: 0 0 0 4px rgba(22,163,74,.18); }
@keyframes floaty { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-10px); } }

/* ---------------- 平台 ---------------- */
.platforms { padding: 16px 0 56px; }
.section-kicker { display: block; font-size: 13px; font-weight: 700; letter-spacing: .12em; color: var(--brand); text-transform: uppercase; }
.section-kicker.center { text-align: center; }
.section-kicker em { font-style: normal; color: var(--amber); letter-spacing: 0; }
.platforms .section-kicker { text-align: center; margin-bottom: 18px; }
.platform-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 18px 12px; }
.platform-row li {
  display: flex; flex-direction: column; align-items: center; gap: 12px;
  width: 132px; padding: 18px 8px 16px; border-radius: 18px;
  color: var(--ink); font-weight: 700; font-size: 15px; text-align: center;
  transition: transform .25s var(--ease), background .25s;
}
.platform-row li:hover { transform: translateY(-4px); background: var(--bg-alt); }
.platform-row img { width: 60px; height: 60px; border-radius: 16px; object-fit: contain; box-shadow: var(--shadow); background: #fff; }
.platform-row li.soon { color: var(--ink-3); font-weight: 500; }
.platform-row li.soon img { filter: grayscale(1); opacity: .55; }
.platform-row small { font-size: 11px; padding: 2px 8px; border-radius: 6px; background: var(--bg-sunken); margin-top: -4px; }

/* ---------------- 分节通用 ---------------- */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; max-width: 760px; margin: 0 auto 52px; }
.section-head.left { text-align: left; margin: 0; }
.section-head h2 { font-size: clamp(28px, 3.6vw, 42px); font-weight: 800; margin-top: 12px; }
.section-sub { color: var(--ink-3); font-size: 17px; margin-top: 14px; }
.section-sub a { color: var(--brand); font-weight: 600; }

/* ---------------- 卡片 ---------------- */
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--r-lg); padding: 30px 26px 28px;
  box-shadow: var(--shadow); transition: transform .25s var(--ease), box-shadow .25s var(--ease), border-color .25s;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: #d9e4ff; }
.card p { color: var(--ink-3); font-size: 15px; text-align: justify; }
/* 玻璃深色方块 + 渐变字形 + 同色光晕。悬停时整块抬起、光晕更亮。 */
.gicon {
  position: relative; width: 56px; height: 56px; border-radius: 16px; display: grid; place-items: center;
  background: linear-gradient(160deg, #263247, #0f172a);
  box-shadow: inset 0 1px 0 rgba(255,255,255,.14), inset 0 -1px 0 rgba(0,0,0,.4), 0 10px 24px -10px var(--g2);
  transition: transform .3s var(--ease), box-shadow .3s var(--ease);
}
.gicon::before {
  content: ""; position: absolute; inset: -6px; border-radius: 22px; z-index: -1;
  background: radial-gradient(closest-side, var(--g1), transparent 70%); opacity: .35; filter: blur(8px);
  transition: opacity .3s;
}
.gicon svg { filter: drop-shadow(0 2px 6px var(--g2)); }
.card:hover .gicon { transform: translateY(-3px) rotate(-3deg); box-shadow: inset 0 1px 0 rgba(255,255,255,.18), inset 0 -1px 0 rgba(0,0,0,.4), 0 16px 30px -10px var(--g2); }
.card:hover .gicon::before { opacity: .7; }
.card h3 { font-size: 20px; margin: 18px 0 10px; }

/* ---------------- 三步 ---------------- */
.steps { display: grid; gap: 64px; }
.step { display: grid; grid-template-columns: 1fr 1.1fr; gap: 48px; align-items: center; }
.step-rev .step-text { order: 2; }
.step-no { display: inline-block; font-size: 13px; font-weight: 800; letter-spacing: .12em; color: var(--brand-2); background: #f1e9ff; padding: 4px 10px; border-radius: 8px; }
.step h3 { font-size: 26px; margin: 14px 0 12px; }
.step p { color: var(--ink-2); font-size: 16px; }
.checks { margin-top: 16px; display: grid; gap: 8px; color: var(--ink-2); font-size: 15px; }
.checks li { display: flex; align-items: center; gap: 10px; }
.checks li::before { content: ""; width: 18px; height: 18px; border-radius: 50%; flex: none; background: var(--grad); -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M12 2a10 10 0 1 0 0 20 10 10 0 0 0 0-20zm-1.2 14.4-3.9-3.9 1.4-1.4 2.5 2.5 5.4-5.4 1.4 1.4z'/%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'%3E%3Cpath d='M12 2a10 10 0 1 0 0 20 10 10 0 0 0 0-20zm-1.2 14.4-3.9-3.9 1.4-1.4 2.5 2.5 5.4-5.4 1.4 1.4z'/%3E%3C/svg%3E") center/contain no-repeat; }

.shot-img {
  margin: 0; border-radius: var(--r-lg); overflow: hidden; background: #fff; border: 1px solid var(--line);
  box-shadow: var(--shadow-lg); transition: transform .35s var(--ease), box-shadow .35s var(--ease);
}
.shot-img img { display: block; width: 100%; height: auto; }
.step:hover .shot-img { transform: translateY(-4px); box-shadow: 0 2px 6px rgba(15,23,42,.06), 0 40px 70px -28px rgba(47,111,224,.35); }

/* ---------------- 数字 ---------------- */
.voices-grid { display: grid; grid-template-columns: 1fr 1.25fr; gap: 56px; align-items: start; }
.voices-copy h2 { font-size: clamp(30px, 3.8vw, 44px); font-weight: 800; margin: 12px 0 16px; }
.voices-copy p { color: var(--ink-2); font-size: 17px; max-width: 30em; }

/* 轮播：一次一张，横向滑动。JS 只改 --i，别的都交给 CSS。 */
.tcarousel { --i: 0; background: #fff; border: 1px solid var(--line); border-radius: var(--r-lg); box-shadow: var(--shadow-lg); overflow: hidden; }
.ttrack { display: flex; width: 100%; transform: translateX(calc(var(--i) * -100%)); transition: transform .55s var(--ease); }
.tslide { flex: 0 0 100%; width: 100%; min-width: 100%; margin: 0; padding: 34px 36px 26px; box-sizing: border-box; }
.stars { display: flex; gap: 4px; margin-bottom: 18px; }
.stars i { width: 20px; height: 20px; background: #e2e8f0; clip-path: polygon(50% 2%, 62% 36%, 98% 38%, 69% 60%, 79% 96%, 50% 75%, 21% 96%, 31% 60%, 2% 38%, 38% 36%); }
.stars i.on { background: #f59e0b; }
.tslide blockquote { margin: 0 0 24px; font-size: 17px; line-height: 1.75; color: var(--ink-2); text-align: justify; min-height: 4.5em; }
.tslide figcaption { display: flex; align-items: center; gap: 14px; }
.tslide b { display: block; font-size: 16px; }
.tslide small { color: var(--ink-3); font-size: 14px; }
.avatar { width: 56px; height: 56px; border-radius: 50%; flex: none; box-shadow: 0 0 0 3px #fff, 0 6px 14px -6px rgba(15,23,42,.35); }
.tnav { display: flex; align-items: center; justify-content: space-between; padding: 0 20px 18px; }
.tarrow { width: 36px; height: 36px; border-radius: 50%; border: 1px solid var(--line); background: #fff; color: var(--ink-2); display: grid; place-items: center; cursor: pointer; transition: background .2s, color .2s, border-color .2s; }
.tarrow:hover { background: var(--brand); border-color: var(--brand); color: #fff; }
.tdots { display: flex; gap: 8px; }
.tdots button { width: 8px; height: 8px; border-radius: 4px; border: 0; padding: 0; background: #cbd5e1; cursor: pointer; transition: width .25s var(--ease), background .25s; }
.tdots button.on { width: 24px; background: var(--brand); }

.stat-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px; margin-top: 88px; }
.stat b { display: block; font-size: 52px; line-height: 1; font-weight: 800; color: var(--ink); font-variant-numeric: tabular-nums; letter-spacing: -.02em; }
.stat strong { display: block; font-size: 20px; font-weight: 800; margin: 16px 0 8px; }
.stat span { display: block; color: var(--ink-3); font-size: 15px; line-height: 1.65; }

/* ---------------- 价格 ---------------- */
.price-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; align-items: stretch; }
.price { position: relative; background: #fff; border: 1px solid var(--line); border-radius: var(--r-lg); padding: 30px 26px 26px; display: flex; flex-direction: column; gap: 10px; box-shadow: var(--shadow); transition: transform .25s var(--ease), box-shadow .25s var(--ease), border-color .25s; }
.price:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: #cfdcf7; }
.price h3 { font-size: 18px; }
.price-qty { display: flex; align-items: baseline; gap: 6px; margin-top: 2px; }
.price-qty b { font-size: 40px; line-height: 1.1; font-weight: 800; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.price-qty small { color: var(--ink-3); font-size: 16px; }
.price-num { display: flex; align-items: baseline; gap: 2px; margin: 4px 0 6px; color: var(--brand); }
.price-num i { font-style: normal; font-size: 18px; font-weight: 700; }
.price-num b { font-size: 28px; font-weight: 800; font-variant-numeric: tabular-nums; }
.price .checks { margin: 4px 0 18px; flex-grow: 1; }
.price .checks li::before { background: var(--green); }
.price .btn { justify-content: center; }
.badge { position: absolute; top: -1px; right: 18px; padding: 5px 12px; border-radius: 0 0 10px 10px; font-size: 12px; font-weight: 700; color: #fff; background: linear-gradient(135deg, #f59e0b, #ea580c); box-shadow: 0 4px 10px -4px #ea580c; }
.price-note { text-align: center; color: var(--ink-3); font-size: 13px; margin-top: 22px; }

/* ---------------- 跑马灯 ---------------- */

/* ---------------- FAQ ---------------- */

/* ---------------- CTA ---------------- */
.cta-banner { position: relative; padding: 96px 0; color: #fff; text-align: center; background: var(--grad); overflow: hidden; }
.cta-banner::before, .cta-banner::after { content: ""; position: absolute; border-radius: 50%; background: rgba(255,255,255,.14); filter: blur(30px); }
.cta-banner::before { width: 420px; height: 420px; left: -120px; top: -160px; }
.cta-banner::after { width: 360px; height: 360px; right: -100px; bottom: -180px; }
.cta-banner h2 { font-size: clamp(28px, 3.6vw, 42px); font-weight: 800; position: relative; }
.cta-banner p { margin-top: 12px; font-size: 17px; opacity: .92; position: relative; }
.cta-banner .hero-actions { justify-content: center; position: relative; }

/* ---------------- 页脚 ---------------- */
.site-footer { background: #0b1220; color: #94a3b8; padding: 64px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 40px; align-items: start; }
.footer-brand .brand { display: inline-flex; align-items: center; padding: 0; color: #fff; line-height: 28px; }
.footer-brand .qr-row { margin-top: 18px; }
.qr-row { display: flex; gap: 12px; }
.qr { width: 92px; height: 92px; border-radius: 12px; background: #fff; color: #0b1220; display: grid; place-items: center; font-size: 12px; font-weight: 700; text-align: center; border: 4px solid #1e293b; }
.site-footer h4 { color: #fff; font-size: 14px; line-height: 28px; margin: 0 0 12px; }
.site-footer a { display: block; padding: 5px 0; font-size: 14px; }
.site-footer a:hover { color: #fff; }
.footer-bottom { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; margin-top: 40px; padding-top: 22px; border-top: 1px solid #1e293b; font-size: 13px; }
.footer-bottom em { font-style: normal; color: var(--amber); }

.to-top { position: fixed; right: 22px; bottom: 22px; width: 44px; height: 44px; border-radius: 50%; display: grid; place-items: center; background: #fff; color: var(--brand); box-shadow: var(--shadow-lg); opacity: 0; transform: translateY(12px); transition: opacity .25s, transform .25s; z-index: 40; }
.to-top.show { opacity: 1; transform: none; }

/* ---------------- 滚动渐显 ---------------- */
/* 只在脚本跑起来之后才藏（html.js）—— 没有 JS 的环境里页面照样全显示。 */
.js .reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.js .reveal.in { opacity: 1; transform: none; }
.delay-1 { transition-delay: .1s; } .delay-2 { transition-delay: .2s; } .delay-3 { transition-delay: .3s; } .delay-4 { transition-delay: .4s; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  .glow, .float-card, .shot-progress span { animation: none !important; }
}

/* ---------------- 响应式 ---------------- */
@media (max-width: 1024px) {
  .feature-grid, .price-grid, .stat-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-grid, .voices-grid { grid-template-columns: 1fr; }
  .hero { padding-top: 56px; }
  .video-frame { transform: none; }
  .fc-1 { left: 8px; } .fc-2 { right: 8px; }
  .step, .step-rev { grid-template-columns: 1fr; }
  .step-rev .step-text { order: 0; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 720px) {
  .nav, .header-cta { display: none; }
  .nav-toggle { display: flex; }
  .site-header.open .nav { display: flex; flex-direction: column; position: absolute; left: 0; right: 0; top: 68px; background: #fff; padding: 12px 20px 18px; border-bottom: 1px solid var(--line); box-shadow: var(--shadow-lg); }
  .site-header.open .nav-toggle span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .site-header.open .nav-toggle span:nth-child(2) { opacity: 0; }
  .site-header.open .nav-toggle span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
  .feature-grid, .price-grid, .stat-grid, .quote-grid, .footer-grid { grid-template-columns: 1fr; }
  .section { padding: 64px 0; }
  .quote-grid { gap: 14px; }
  .hero h1 { font-size: 34px; }
}