@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;500;600;700&family=Fira+Sans:wght@300;400;500;600;700;900&display=swap');

:root {
  --ink: #000000;
  --paper: #ffffff;
  --muted: #5a5a5a;
  --line: rgba(0, 0, 0, .16);
  --hair: rgba(255, 255, 255, .38);
  --glass: rgba(255, 255, 255, .74);
  --r: 28px;
  --bar: 74px;
  --sans: 'Fira Sans', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --mono: 'Fira Code', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 400 17px/1.72 var(--sans);
  letter-spacing: .004em;
  padding-bottom: calc(var(--bar) + 26px);
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; }
h1, h2, h3 { margin: 0; font-weight: 700; line-height: 1.14; letter-spacing: -.024em; }
p { margin: 0 0 1em; }
:focus-visible { outline: 2px solid var(--ink); outline-offset: 3px; }

/* ---------- 满屏首屏 ---------- */
.hero {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 100vh;
  min-height: 100svh;
  background: #000;
  color: #fff;
  overflow: hidden;
  isolation: isolate;
}
.hero-empty { background: radial-gradient(circle at 50% 26%, #1b1b1b, #000 70%); }

.hero-fig {
  position: absolute;
  inset: 0;
  margin: 0;
  z-index: 0;
}
.hero-fig img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform: scale(1.05);
  will-change: transform;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  background: linear-gradient(180deg, rgba(0,0,0,.62), rgba(0,0,0,.36) 46%, rgba(0,0,0,.86));
}

.hero-body {
  position: relative;
  z-index: 2;
  width: min(760px, 88vw);
  text-align: center;
  padding: 95px 0 calc(var(--bar) + 52px);
}
.hero-mark {
  margin: 0 0 20px;
  font-family: var(--mono);
  font-size: .74rem;
  font-weight: 500;
  letter-spacing: .38em;
  text-indent: .38em;
  color: rgba(255,255,255,.82);
}
.hero h1 {
  font-size: clamp(2.05rem, 6.6vw, 4.4rem);
  font-weight: 900;
  letter-spacing: -.045em;
  text-wrap: balance;
  text-shadow: 0 2px 28px rgba(0,0,0,.35);
}
.hero-desc {
  margin: 22px auto 0;
  max-width: 44ch;
  font-size: 1rem;
  line-height: 1.72;
  color: rgba(255,255,255,.88);
}
.hero-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 30px;
  min-height: 50px;
  padding: 0 30px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,.62);
  background: rgba(255,255,255,.14);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  color: #fff;
  font-size: .95rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-decoration: none;
  transition: background .25s ease, color .25s ease, transform .25s ease;
}
.hero-cta:hover { background: #fff; color: #000; transform: translateY(-2px); }
.hero :focus-visible { outline-color: #fff; }

.hero-cap {
  position: absolute;
  left: 16px;
  bottom: calc(var(--bar) + 18px);
  z-index: 2;
  max-width: 78vw;
  margin: 0;
  padding: 8px 15px;
  border-radius: 999px;
  border: 1px solid var(--hair);
  background: rgba(255,255,255,.15);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .04em;
  color: #fff;
}

/* ---------- 底部固定条 ---------- */
.bar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 60;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 12px calc(9px + env(safe-area-inset-bottom));
  background: rgba(255,255,255,.84);
  -webkit-backdrop-filter: blur(18px) saturate(1.25);
  backdrop-filter: blur(18px) saturate(1.25);
  border-top: 1px solid var(--line);
}
.brand {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 4px 4px 4px 2px;
  text-decoration: none;
}
.brand-logo {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  object-fit: cover;
  border: 1px solid var(--ink);
}
.brand-name {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: -.02em;
  white-space: nowrap;
}
.bar-nav {
  flex: 1 1 auto;
  min-width: 0;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}
.bar-nav::-webkit-scrollbar { display: none; }
.bar-nav p {
  display: flex;
  align-items: center;
  gap: 2px;
  margin: 0;
  width: max-content;
}
.bar-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  border-radius: 999px;
  font-size: 1rem;
  font-weight: 500;
  white-space: nowrap;
  text-decoration: none;
  transition: background .2s ease, color .2s ease;
}
.bar-nav a::before {
  content: "";
  width: 5px;
  height: 5px;
  margin-right: 7px;
  border-radius: 50%;
  background: currentColor;
  opacity: .45;
}
.bar-nav a:hover { background: var(--ink); color: var(--paper); }
.bar-nav a:hover::before { opacity: 1; }

.bar-tel {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 44px;
  padding: 0 16px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
}
.bar-tel .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

/* ---------- 主体网格 ---------- */
.wrap {
  width: min(1180px, 92vw);
  margin: 0 auto;
  padding: 42px 0 76px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
}

.side {
  border: 1px solid var(--line);
  border-radius: var(--r);
  background: var(--glass);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  padding: 22px 20px;
  box-shadow: 0 18px 44px -32px rgba(0,0,0,.6);
}
.side h2 {
  font-size: 1rem;
  letter-spacing: .16em;
  text-indent: .16em;
}
.side hr {
  border: 0;
  height: 2px;
  width: 42px;
  background: var(--ink);
  margin: 11px 0 14px;
}
.side-links { display: grid; gap: 2px; margin: 0; }
.side-links a {
  display: flex;
  align-items: center;
  min-height: 40px;
  padding: 0 4px;
  font-size: .95rem;
  text-decoration: none;
  border-bottom: 1px dashed transparent;
  transition: border-color .2s ease, padding-left .2s ease;
}
.side-links a:hover { border-bottom-color: var(--ink); padding-left: 8px; }

.content { min-width: 0; }
.prose {
  max-width: 764px;
  font-size: 1.0625rem;
  line-height: 1.78;
}
.prose > div {
  padding: 6px 0 40px;
  scroll-margin-top: 30px;
  scroll-margin-bottom: calc(var(--bar) + 26px);
}
.prose > div + div {
  border-top: 1px solid var(--line);
  padding-top: 42px;
}
.prose h2 {
  font-size: clamp(1.55rem, 3.6vw, 2.5rem);
  letter-spacing: -.035em;
  margin: 0 0 14px;
  text-wrap: balance;
}
.prose h3 { font-size: 1.26rem; margin: 30px 0 10px; }
.prose hr {
  border: 0;
  height: 2px;
  width: 62px;
  background: var(--ink);
  margin: 0 0 24px;
}
.prose p { max-width: 64ch; }
.prose > div:first-of-type > p:first-of-type::first-letter {
  float: left;
  font-size: 3.5em;
  line-height: .8;
  font-weight: 900;
  padding: 8px 12px 0 0;
  letter-spacing: -.02em;
}
.prose a {
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}
.prose blockquote {
  margin: 30px 0;
  padding: 4px 0 4px 22px;
  border-left: 4px solid var(--ink);
  font-size: 1.16rem;
  font-weight: 600;
  line-height: 1.5;
  letter-spacing: -.02em;
}
.prose blockquote p { margin: .4em 0; }
.prose figure { margin: 30px 0; }
.prose img { border-radius: 16px; }
.prose figcaption {
  margin-top: 9px;
  font-family: var(--mono);
  font-size: .78rem;
  letter-spacing: .03em;
  color: var(--muted);
}
.prose ul, .prose ol { padding-left: 1.25em; margin: 0 0 1.2em; }
.prose li { margin: .35em 0; }
.prose code, .prose kbd {
  font-family: var(--mono);
  font-size: .92em;
  background: rgba(0,0,0,.06);
  padding: .12em .4em;
  border-radius: 6px;
}
.prose pre {
  font-family: var(--mono);
  font-size: .88rem;
  line-height: 1.6;
  overflow-x: auto;
  padding: 18px;
  border-radius: 18px;
  background: #000;
  color: #fff;
}
.prose pre code { background: none; padding: 0; }
.prose table { width: 100%; border-collapse: collapse; font-size: .95rem; }
.prose th, .prose td { border-bottom: 1px solid var(--line); padding: 10px 8px; text-align: left; }

/* ---------- 页脚 ---------- */
.foot {
  width: min(1180px, 92vw);
  margin: 0 auto;
  padding: 54px 0 34px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 26px;
  border-top: 2px solid var(--ink);
}
.foot-brand {
  grid-column: 1 / -1;
  margin: 0 0 6px;
  font-size: clamp(2.3rem, 9vw, 5.4rem);
  font-weight: 900;
  line-height: .94;
  letter-spacing: -.055em;
  word-break: break-word;
}
.foot-col {
  margin: 0;
  font-size: .95rem;
  line-height: 1.95;
  color: var(--muted);
}
.foot-col a {
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .2s ease, color .2s ease;
}
.foot-col a:hover { color: var(--ink); border-bottom-color: var(--ink); }
.foot-cr {
  grid-column: 1 / -1;
  margin-top: 8px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: .78rem;
  color: var(--muted);
}

/* ---------- 动效 ---------- */
.reveal {
  opacity: 0;
  transform: translate3d(0, 26px, 0);
  transition: opacity .7s ease, transform .75s cubic-bezier(.2, .7, .2, 1);
}
.reveal.is-in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (min-width: 900px) {
  .wrap {
    grid-template-columns: 252px minmax(0, 1fr);
    gap: 56px;
    align-items: start;
    padding-top: 64px;
  }
  .side { position: sticky; top: 26px; }
}

@media (min-width: 820px) {
  .foot { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

@media (min-width: 1040px) {
  .prose > div:first-of-type {
    column-count: 2;
    column-gap: 46px;
  }
  .prose > div:first-of-type h2,
  .prose > div:first-of-type hr { column-span: all; }
  .prose > div:first-of-type p { max-width: none; }
}

@media (max-width: 560px) {
  body { font-size: 16.5px; }
  .hero-body { padding-top: 78px; }
  .hero-desc { font-size: .96rem; }
  .brand-name { font-size: .95rem; }
  .bar-nav a { padding: 0 10px; font-size: .95rem; }
  .bar-tel { padding: 0 13px; font-size: .95rem; }
  .hero-cap { font-size: .66rem; padding: 7px 12px; left: 12px; }
  .foot { padding-top: 42px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .hero-fig img { transform: none; }
  .hero-cta:hover { transform: none; }
}

button[aria-expanded]{min-width:44px;min-height:44px}