:root {
  color-scheme: light dark;
  --bg: #fff;
  --bg-alt: #f5f5f7;
  --ink: #1d1d1f;
  --muted: #6e6e73;
  --line: #d9d9de;
  --accent: #1a6a78;
  --nav: rgba(255, 255, 255, .78);
  --shadow: 0 18px 50px rgba(0, 0, 0, .14);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111214;
    --bg-alt: #1b1c1f;
    --ink: #f5f5f7;
    --muted: #a1a1a6;
    --line: #38383c;
    --accent: #6cc3d1;
    --nav: rgba(17, 18, 20, .78);
    --shadow: 0 18px 50px rgba(0, 0, 0, .5);
  }
}

* { box-sizing: border-box; margin: 0; }
html { scroll-behavior: smooth; scroll-padding-top: 64px; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.7 -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; height: auto; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

.wrap { width: min(1040px, 100% - 40px); margin-inline: auto; }
section { padding-block: 88px; }
.alt { background: var(--bg-alt); }
h1, h2, h3 { font-weight: 600; line-height: 1.2; }
h2 { font-size: clamp(30px, 4.4vw, 42px); margin-bottom: 40px; }
h3 { font-size: 19px; margin-bottom: 6px; }
.muted { color: var(--muted); }

/* 导航 */
.nav { position: sticky; top: 0; z-index: 10; background: var(--nav); backdrop-filter: saturate(180%) blur(20px); -webkit-backdrop-filter: saturate(180%) blur(20px); border-bottom: 1px solid var(--line); }
.nav .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; height: 52px; }
.brand { display: flex; align-items: center; gap: 8px; color: var(--ink); font-weight: 600; }
.brand:hover { text-decoration: none; }
.brand img { width: 26px; height: 26px; }
.nav ul { display: flex; gap: clamp(14px, 3vw, 28px); list-style: none; padding: 0; font-size: 14px; }
.nav ul a { color: var(--muted); }
.nav ul a:hover { color: var(--ink); text-decoration: none; }

/* 首屏 */
.hero { padding-block: 72px 88px; text-align: center; }
.hero .icon { width: 88px; height: 88px; margin: 0 auto 14px; }
.hero .name { font-size: 19px; font-weight: 600; margin-bottom: 8px; }
.hero h1 { font-size: clamp(34px, 9vw, 76px); margin-bottom: 18px; }
.hero .lead { font-size: clamp(18px, 2.4vw, 22px); line-height: 1.6; max-width: 34em; margin: 0 auto 14px; color: var(--muted); }
.hero .meta { font-size: 15px; color: var(--muted); margin-bottom: 48px; }
.shot { width: 100%; border-radius: 14px; box-shadow: var(--shadow); }
.swatches { display: flex; justify-content: center; flex-wrap: wrap; gap: 8px 20px; margin-top: 24px; }
.swatch { display: flex; align-items: center; gap: 8px; padding: 6px 12px 6px 6px; border: 0; border-radius: 999px; background: none; color: var(--muted); font: inherit; font-size: 14px; cursor: pointer; }
.swatch span { width: 28px; height: 28px; border-radius: 50%; background-size: 280%; background-position: center; box-shadow: inset 0 0 0 1px rgba(0, 0, 0, .14); }
.swatch:hover { color: var(--ink); }
.swatch[aria-pressed="true"] { color: var(--ink); font-weight: 600; background: var(--bg-alt); }
.note { margin-top: 16px; font-size: 13px; color: var(--muted); }

/* 栅格 */
.steps, .features, .shots { display: grid; gap: 32px; }
.steps { grid-template-columns: repeat(3, 1fr); }
.steps img { border-radius: 10px; margin-bottom: 18px; box-shadow: 0 8px 24px rgba(0, 0, 0, .12); }
.steps p, .features p { color: var(--muted); font-size: 16px; }
.features { grid-template-columns: repeat(4, 1fr); margin-bottom: 56px; }
.shots { grid-template-columns: repeat(2, 1fr); align-items: start; }
.shots img { border-radius: 12px; box-shadow: 0 10px 30px rgba(0, 0, 0, .16); }
.shots figcaption { margin-top: 12px; font-size: 14px; color: var(--muted); text-align: center; }

/* 信息列表 */
.info { max-width: 720px; }
.info div { display: grid; grid-template-columns: 8em 1fr; gap: 16px; padding-block: 14px; border-top: 1px solid var(--line); }
.info div:last-child { border-bottom: 1px solid var(--line); }
.info dt { color: var(--muted); }
.columns { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; }
.columns h2 { margin-bottom: 24px; }
.product { display: flex; align-items: center; gap: 14px; padding-block: 12px; border-top: 1px solid var(--line); }
.product img { width: 52px; height: 52px; }
.product strong { display: block; font-weight: 600; }
.product small { font-size: 14px; color: var(--muted); }
.mail { display: inline-block; font-size: clamp(24px, 4vw, 34px); font-weight: 600; word-break: break-all; margin-bottom: 8px; }

/* 首屏视频 */
.stage { position: relative; }
.stage video { display: block; width: 100%; height: auto; aspect-ratio: 16 / 10; background: #16343d; }
.toggle { position: absolute; right: 12px; bottom: 12px; display: grid; place-items: center; width: 36px; height: 36px; padding: 0; border: 0; border-radius: 50%; background: rgba(0, 0, 0, .5); color: #fff; font-size: 13px; line-height: 1; cursor: pointer; -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px); }
.toggle:hover { background: rgba(0, 0, 0, .68); }

/* 手感（深色区块） */
.night { background: #0f2a32; color: #f5f5f7; }
.night .sub { color: #b4c6ca; font-size: clamp(17px, 2vw, 20px); max-width: 34em; margin: -24px 0 40px; }
.feels { display: grid; grid-template-columns: repeat(2, 1fr); gap: 32px; }
.feels video { display: block; width: 100%; height: auto; aspect-ratio: 16 / 10; border-radius: 12px; background: #16343d; margin-bottom: 14px; }
.feels p { color: #b4c6ca; font-size: 16px; }
.night .note { color: #8fa6ab; margin-top: 28px; }
.night :focus-visible { outline-color: #fff; }

/* 图案墙 */
.lede { color: var(--muted); font-size: clamp(17px, 2vw, 20px); max-width: 34em; margin: -24px 0 40px; }
.patterns { display: grid; grid-template-columns: repeat(6, 1fr); gap: 20px 14px; list-style: none; padding: 0; }
.patterns img { width: 100%; border-radius: 8px; box-shadow: inset 0 0 0 1px rgba(0, 0, 0, .1), 0 4px 12px rgba(0, 0, 0, .1); margin-bottom: 8px; }
.patterns li { font-size: 13px; color: var(--muted); text-align: center; }

/* 细节 */
.details { display: grid; grid-template-columns: repeat(3, 1fr); gap: 36px 32px; }
.details p { color: var(--muted); font-size: 16px; }

/* 页面底部的开发者、产品和联系方式：字号收小 */
.fine { padding-block: 64px; font-size: 15px; line-height: 1.65; }
.fine .columns { grid-template-columns: 1.5fr 1fr 1.2fr; gap: 48px; }
.fine h2 { font-size: 20px; margin-bottom: 16px; }
.fine .info { max-width: none; }
.fine .info div { grid-template-columns: 5.5em 1fr; gap: 12px; padding-block: 9px; }
.fine .product img { width: 40px; height: 40px; }
.fine .product small { font-size: 13px; }
.fine .mail { font-size: 17px; margin-bottom: 4px; }
.fine p { margin-bottom: 14px; }

@media (max-width: 860px) {
  .patterns { grid-template-columns: repeat(4, 1fr); }
  .details { grid-template-columns: repeat(2, 1fr); }
  .fine .columns { grid-template-columns: 1fr; gap: 40px; }
}
@media (max-width: 600px) {
  .feels, .details { grid-template-columns: 1fr; }
  .patterns { grid-template-columns: repeat(3, 1fr); }
}

/* 页脚 */
footer { padding-block: 36px 44px; background: var(--bg-alt); border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }
footer strong { display: block; color: var(--ink); font-size: 14px; font-weight: 600; }
footer ul { display: flex; flex-wrap: wrap; gap: 6px 20px; list-style: none; padding: 0; margin-block: 12px; }
footer a { color: inherit; text-decoration: underline; text-underline-offset: 2px; }

/* 说明页 */
.doc { padding-block: 64px 88px; max-width: 720px; }
.doc h1 { font-size: clamp(34px, 5vw, 44px); margin-bottom: 8px; }
.doc h2 { font-size: 22px; margin: 40px 0 8px; }
.doc ul { padding-left: 1.2em; }
.doc li + li { margin-top: 6px; }

@media (max-width: 860px) {
  section { padding-block: 64px; }
  .hero { padding-block: 48px 64px; }
  .features { grid-template-columns: repeat(2, 1fr); }
  .columns { grid-template-columns: 1fr; gap: 64px; }
}
@media (max-width: 600px) {
  .steps, .features, .shots { grid-template-columns: 1fr; }
  .info div { grid-template-columns: 6em 1fr; }
}