/* images two 图 static landing page. Tokens mirror lib/web/theme/web_theme.dart. */
:root {
  --paper: #f7f7f5;
  --surface: #ffffff;
  --sunken: #f0f0ec;
  --line: #e6e5e0;
  --ink: #18181b;
  --muted: #71717a;
  --mint: #0c8460;
  --mint-strong: #086b4d;
  --mint-bright: #12a37a;
  --mint-soft: #e3f6ef;
  --coral: #ff6b4a;
  --dark: #0e0e11;
  --dark-2: #1c1c21;
  --radius-sm: 10px;
  --radius: 14px;
  --radius-lg: 20px;
  --font: "PingFang SC", "HarmonyOS Sans SC", "MiSans", "Microsoft YaHei UI", "Microsoft YaHei", "Noto Sans SC", Inter, system-ui, -apple-system, "Segoe UI", sans-serif;
  color-scheme: light;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button, textarea { font: inherit; color: inherit; }
h1, h2, h3, p { margin: 0; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); border: 0; }
:focus-visible { outline: 2px solid var(--mint-bright); outline-offset: 2px; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  height: 40px; padding: 0 18px; border-radius: var(--radius-sm);
  font-size: 14px; font-weight: 600; white-space: nowrap; cursor: pointer;
  border: 1px solid transparent; transition: background .15s, border-color .15s, transform .15s;
}
.btn--primary { background: var(--mint); color: #fff; }
.btn--primary:hover { background: var(--mint-strong); }
.btn--ghost { color: inherit; border-color: rgba(255,255,255,.18); }
.btn--ghost:hover { background: rgba(255,255,255,.08); }
.btn--lg { height: 48px; padding: 0 22px; font-size: 15px; }
.btn:active { transform: translateY(1px); }

/* Nav */
.nav {
  position: sticky; top: 0; z-index: 20;
  background: rgba(14,14,17,.82); color: #fff;
  backdrop-filter: saturate(160%) blur(14px); -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid rgba(255,255,255,.06);
}
.nav__inner { max-width: 1240px; margin: 0 auto; height: 64px; padding: 0 24px; display: flex; align-items: center; gap: 32px; }
.nav__links { display: flex; gap: 26px; font-size: 14px; color: rgba(255,255,255,.7); }
.nav__links a:hover { color: #fff; }
.nav__actions { margin-left: auto; display: flex; gap: 10px; }
.is-signed-in [data-auth="guest"] { display: none; }

.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; font-size: 17px; letter-spacing: -.01em; }
.brand__mark { position: relative; width: 30px; height: 30px; border-radius: 8px; background: var(--dark-2); flex: none; }
.brand__mark i { position: absolute; width: 14px; height: 14px; border-radius: 3px; transform: rotate(-10deg); }
.brand__mark i:first-child { left: 6px; top: 5px; background: var(--mint-bright); }
.brand__mark i:last-child { right: 5px; bottom: 5px; background: var(--coral); }

/* Hero */
.hero { position: relative; background: var(--dark); color: #fff; overflow: hidden; }
.hero::before {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background:
    radial-gradient(600px 400px at 12% 10%, rgba(18,163,122,.22), transparent 70%),
    radial-gradient(500px 360px at 40% 100%, rgba(255,107,74,.12), transparent 70%);
}
.hero__inner {
  position: relative; max-width: 1240px; margin: 0 auto; padding: 72px 24px 56px;
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 56px; align-items: center;
}
.eyebrow { font-size: 13px; font-weight: 600; letter-spacing: .04em; color: rgba(255,255,255,.62); margin-bottom: 16px; }
.eyebrow--mint { color: var(--mint); }
.eyebrow--coral { color: #e0512f; }
.hero h1 { font-size: clamp(34px, 4.4vw, 52px); line-height: 1.16; font-weight: 800; letter-spacing: -.02em; }
.hl { background: linear-gradient(90deg, #5fe0b5, #ffb199); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero__lead { margin-top: 20px; font-size: 17px; line-height: 1.7; color: rgba(255,255,255,.72); max-width: 34em; }
.hero__note { margin-top: 12px; font-size: 13px; color: rgba(255,255,255,.5); }
.hero__credit { position: relative; text-align: center; font-size: 12px; color: rgba(255,255,255,.38); padding: 0 24px 20px; }

.composer {
  margin-top: 32px; background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.14);
  border-radius: var(--radius-lg); padding: 14px; transition: border-color .15s, background .15s;
}
.composer:focus-within { border-color: rgba(95,224,181,.6); background: rgba(255,255,255,.08); }
.composer textarea {
  display: block; width: 100%; resize: none; border: 0; outline: 0; background: transparent;
  color: #fff; font-size: 16px; line-height: 1.6; padding: 4px 6px;
}
.composer textarea::placeholder { color: rgba(255,255,255,.4); }
.composer__bar { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 10px; flex-wrap: wrap; }
.chips { display: flex; gap: 8px; flex-wrap: wrap; }
.chip {
  height: 32px; padding: 0 12px; border-radius: 999px; cursor: pointer; font-size: 13px;
  background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.12); color: rgba(255,255,255,.82);
}
.chip:hover { background: rgba(255,255,255,.12); color: #fff; }

/* Hero image wall */
.wall {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; height: 620px;
  -webkit-mask-image: linear-gradient(to bottom, transparent, #000 10%, #000 88%, transparent);
  mask-image: linear-gradient(to bottom, transparent, #000 10%, #000 88%, transparent);
}
.wall__col { overflow: hidden; }
.wall__col--offset .wall__track { animation-duration: 70s; animation-direction: reverse; }
.wall__col--wide .wall__track { animation-duration: 64s; }
.wall__track { display: flex; flex-direction: column; gap: 12px; animation: wall-scroll 56s linear infinite; }
.wall__track img { width: 100%; border-radius: var(--radius); background: var(--dark-2); }
.wall:hover .wall__track { animation-play-state: paused; }
@keyframes wall-scroll { from { transform: translateY(0); } to { transform: translateY(-50%); } }

/* Sections */
.section { max-width: 1240px; margin: 0 auto; padding: 96px 24px; }
.section--sunken {
  max-width: none; background: var(--sunken);
  padding-left: max(24px, calc((100% - 1192px) / 2));
  padding-right: max(24px, calc((100% - 1192px) / 2));
}
.section__head { max-width: 640px; margin-bottom: 40px; }
.section__head h2, .kit h2, .cta h2 { font-size: clamp(26px, 3vw, 36px); line-height: 1.25; font-weight: 800; letter-spacing: -.015em; }
.section__head p:not(.eyebrow) { margin-top: 12px; color: var(--muted); font-size: 16px; }

/* Scene cards */
.scenes { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); grid-auto-rows: 260px; gap: 16px; }
.scene {
  position: relative; padding: 0; border: 0; border-radius: var(--radius-lg); overflow: hidden; cursor: pointer;
  background: var(--sunken); text-align: left;
}
.scene--tall { grid-row: span 2; }
.scene img { width: 100%; height: 100%; object-fit: cover; transition: transform .5s ease; }
.scene:hover img { transform: scale(1.04); }
.scene::after { content: ""; position: absolute; inset: 0; background: linear-gradient(to top, rgba(0,0,0,.62), transparent 52%); }
.scene__text { position: absolute; left: 18px; right: 18px; bottom: 16px; z-index: 1; color: #fff; display: flex; flex-direction: column; gap: 2px; }
.scene__text strong { font-size: 18px; font-weight: 700; }
.scene__text em { font-style: normal; font-size: 13px; color: rgba(255,255,255,.78); }
.scene__text strong::after { content: " →"; opacity: 0; transition: opacity .2s; }
.scene:hover .scene__text strong::after { opacity: 1; }

/* Product kit */
.kit { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: 56px; align-items: center; }
.kit__copy p:not(.eyebrow) { margin-top: 14px; color: var(--muted); font-size: 16px; }
.ticks { list-style: none; padding: 0; margin: 24px 0 28px; display: grid; gap: 10px; }
.ticks li { position: relative; padding-left: 28px; }
.ticks li::before {
  content: ""; position: absolute; left: 0; top: 5px; width: 18px; height: 18px; border-radius: 50%;
  background: var(--mint-soft) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath d='M4 8.5l2.5 2.5L12 5.5' fill='none' stroke='%230C8460' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center/12px no-repeat;
}
.kit__demo { display: grid; grid-template-columns: minmax(0, 1fr) auto minmax(0, 1.3fr); gap: 16px; align-items: center; }
.kit figure { margin: 0; position: relative; }
.kit figure img { width: 100%; border-radius: var(--radius); background: var(--surface); box-shadow: 0 1px 2px rgba(0,0,0,.04); }
.kit figcaption { margin-top: 8px; font-size: 13px; color: var(--muted); }
.kit__source img { border: 2px dashed var(--line); padding: 6px; }
.kit__arrow { font-size: 28px; color: var(--mint); }
.kit__grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.kit__grid figure:first-child { grid-column: span 2; }
.kit__grid figure:first-child img { aspect-ratio: 2 / 1; object-fit: cover; }

/* Steps */
.steps { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.steps li { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 28px; }
.steps__num { font-size: 13px; font-weight: 700; color: var(--mint); font-variant-numeric: tabular-nums; }
.steps h3 { margin-top: 14px; font-size: 18px; font-weight: 700; }
.steps p { margin-top: 8px; color: var(--muted); }

/* Pricing */
.prices { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.price { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 28px; display: flex; flex-direction: column; gap: 6px; }
.price--featured { border-color: var(--mint); box-shadow: 0 0 0 3px var(--mint-soft); }
.price__tier { font-size: 14px; font-weight: 700; color: var(--muted); }
.price__value { font-size: 40px; font-weight: 800; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.price__value[data-loaded]::before { content: "¥"; font-size: 20px; margin-right: 2px; vertical-align: 14px; color: var(--muted); }
.price__hint { color: var(--muted); font-size: 14px; }
.prices__note { margin-top: 16px; font-size: 13px; color: var(--muted); }

/* FAQ */
.faq { display: grid; gap: 10px; max-width: 820px; }
.faq details { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 0 22px; }
.faq summary { cursor: pointer; list-style: none; padding: 18px 0; font-weight: 600; font-size: 16px; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--muted); font-size: 20px; line-height: 1; transition: transform .2s; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details p { padding: 0 0 18px; color: var(--muted); }

/* Final CTA + footer */
.cta { background: var(--dark); color: #fff; text-align: center; padding: 96px 24px; position: relative; overflow: hidden; }
.cta::before { content: ""; position: absolute; inset: 0; background: radial-gradient(520px 260px at 50% 0%, rgba(18,163,122,.28), transparent 70%); }
.cta > * { position: relative; }
.cta p { margin: 12px 0 28px; color: rgba(255,255,255,.66); font-size: 16px; }
.footer { background: var(--dark); color: rgba(255,255,255,.5); border-top: 1px solid rgba(255,255,255,.06); }
.footer__inner { max-width: 1240px; margin: 0 auto; padding: 24px; display: flex; justify-content: space-between; align-items: center; gap: 16px; font-size: 13px; }
.brand--small { color: #fff; font-size: 15px; }

/* Responsive */
@media (max-width: 1080px) {
  .hero__inner { grid-template-columns: 1fr; gap: 40px; padding-top: 56px; }
  .wall { height: 440px; }
  .scenes { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .kit { grid-template-columns: 1fr; gap: 40px; }
}
@media (max-width: 720px) {
  body { font-size: 14px; }
  .nav__inner { padding: 0 16px; gap: 12px; height: 56px; }
  .nav__links { display: none; }
  .nav__actions .btn { height: 36px; padding: 0 14px; }
  .hero__inner { padding: 40px 16px 32px; }
  .hero__lead { font-size: 15px; }
  .composer__bar .btn { width: 100%; }
  .wall { grid-template-columns: repeat(2, minmax(0, 1fr)); height: 360px; gap: 10px; }
  .wall__col--wide { display: none; }
  .section { padding: 64px 16px; }
  .scenes { grid-template-columns: repeat(2, minmax(0, 1fr)); grid-auto-rows: 200px; gap: 10px; }
  .scene--tall { grid-row: span 2; }
  .scene__text strong { font-size: 16px; }
  .kit__demo { grid-template-columns: 1fr; }
  .kit__arrow { transform: rotate(90deg); justify-self: center; }
  .kit__source { max-width: 220px; justify-self: center; }
  .steps, .prices { grid-template-columns: 1fr; }
  .footer__inner { flex-direction: column; text-align: center; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .wall__track { animation: none; }
  .scene img { transition: none; }
}