/* =========================================================
   即刻建站 · 全局设计系统 (深色高端质感)
   ========================================================= */

:root {
  /* 色彩 — 深空黑底 + 香槟金点缀 */
  --bg-900: #07070b;
  --bg-800: #0c0c12;
  --bg-700: #121219;
  --bg-600: #181822;
  --surface: rgba(255, 255, 255, 0.035);
  --surface-2: rgba(255, 255, 255, 0.06);
  --border: rgba(255, 255, 255, 0.09);
  --border-strong: rgba(255, 255, 255, 0.16);

  --text-100: #f5f4ef;
  --text-200: #cfcdc6;
  --text-300: #9a9890;
  --text-400: #6e6c66;

  --gold: #d8b775;
  --gold-soft: #e8d3a3;
  --gold-deep: #b8945a;
  --gold-glow: rgba(216, 183, 117, 0.22);

  --accent: #8ab4ff;
  --ok: #6fce9f;

  --grad-gold: linear-gradient(135deg, #e8d3a3 0%, #d8b775 45%, #b8945a 100%);
  --grad-surface: linear-gradient(160deg, rgba(255,255,255,0.07), rgba(255,255,255,0.01));

  --shadow-sm: 0 2px 12px rgba(0,0,0,0.4);
  --shadow-lg: 0 24px 60px rgba(0,0,0,0.55);
  --shadow-gold: 0 18px 50px rgba(216,183,117,0.14);

  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 24px;

  --maxw: 1200px;
  --nav-h: 72px;

  --ff-serif: "Noto Serif SC", "Playfair Display", Georgia, "Songti SC", serif;
  --ff-sans: "Inter", "Noto Sans SC", -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

/* ---------- 复位 ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--ff-sans);
  background: var(--bg-900);
  color: var(--text-200);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4 { color: var(--text-100); font-family: var(--ff-serif); font-weight: 600; line-height: 1.2; margin: 0; letter-spacing: 0.01em; }
p { margin: 0 0 1em; }
ul { margin: 0; padding: 0; list-style: none; }

/* 双语切换：默认中文显示，英文隐藏 */
html[lang="en"] [lang="zh"] { display: none !important; }
html:not([lang="en"]) [lang="en"] { display: none !important; }

/* ---------- 布局工具 ---------- */
.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.section { padding: 110px 0; position: relative; }
.section--tight { padding: 78px 0; }
.center { text-align: center; }
.lead { color: var(--text-300); font-size: 1.06rem; max-width: 62ch; }
.mx-auto { margin-left: auto; margin-right: auto; }
.gold-text {
  background: var(--grad-gold);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* 背景装饰光斑 */
.bg-aura { position: fixed; inset: 0; z-index: 0; pointer-events: none; overflow: hidden; }
.bg-aura::before, .bg-aura::after {
  content: ""; position: absolute; border-radius: 50%; filter: blur(120px); opacity: 0.5;
}
.bg-aura::before { width: 540px; height: 540px; background: radial-gradient(circle, var(--gold-glow), transparent 70%); top: -160px; left: -120px; }
.bg-aura::after { width: 620px; height: 620px; background: radial-gradient(circle, rgba(138,180,255,0.12), transparent 70%); bottom: -200px; right: -160px; }

/* ---------- 导航 ---------- */
.nav {
  position: fixed; top: 0; left: 0; right: 0; height: var(--nav-h); z-index: 50;
  display: flex; align-items: center;
  background: rgba(7,7,11,0.55); backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent; transition: border-color .3s, background .3s;
}
.nav.scrolled { background: rgba(7,7,11,0.85); border-bottom-color: var(--border); }
.nav__inner { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; display: flex; align-items: center; justify-content: space-between; }
.brand { display: flex; align-items: center; gap: 10px; font-family: var(--ff-serif); font-size: 1.18rem; color: var(--text-100); font-weight: 600; }
.brand__mark { width: 30px; height: 30px; }
.nav__links { display: flex; align-items: center; gap: 30px; }
.nav__links a { color: var(--text-300); font-size: 0.94rem; transition: color .2s; position: relative; }
.nav__links a:hover { color: var(--text-100); }
.nav__links a::after { content: ""; position: absolute; left: 0; bottom: -6px; height: 1px; width: 0; background: var(--gold); transition: width .25s var(--ease); }
.nav__links a:hover::after { width: 100%; }
.nav__right { display: flex; align-items: center; gap: 14px; }
.lang-toggle {
  display: inline-flex; border: 1px solid var(--border); border-radius: 999px; overflow: hidden; font-size: 0.8rem;
}
.lang-toggle button { background: transparent; border: 0; color: var(--text-300); padding: 6px 11px; cursor: pointer; font-family: var(--ff-sans); transition: all .2s; }
.lang-toggle button.active { background: var(--gold); color: #1a1407; font-weight: 600; }
.nav__burger { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav__burger span { width: 22px; height: 2px; background: var(--text-100); border-radius: 2px; transition: .3s; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 9px; padding: 13px 26px; border-radius: 999px;
  font-size: 0.95rem; font-weight: 600; cursor: pointer; border: 1px solid transparent; transition: all .25s var(--ease);
  font-family: var(--ff-sans);
}
.btn--gold { background: var(--grad-gold); color: #1a1407; box-shadow: var(--shadow-gold); }
.btn--gold:hover { transform: translateY(-2px); box-shadow: 0 22px 60px rgba(216,183,117,0.28); }
.btn--ghost { background: var(--surface); color: var(--text-100); border-color: var(--border-strong); }
.btn--ghost:hover { border-color: var(--gold); color: var(--gold-soft); background: var(--surface-2); }
.btn--sm { padding: 9px 18px; font-size: 0.86rem; }

/* ---------- 英雄区 ---------- */
.hero { position: relative; padding: calc(var(--nav-h) + 90px) 0 100px; z-index: 1; }
.hero__eyebrow {
  display: inline-flex; align-items: center; gap: 8px; font-size: 0.82rem; letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--gold-soft); border: 1px solid var(--border); padding: 7px 16px; border-radius: 999px; margin-bottom: 26px;
  background: var(--surface);
}
.hero__eyebrow .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--gold); box-shadow: 0 0 10px var(--gold); }
.hero h1 { font-size: clamp(2.4rem, 5.4vw, 4.3rem); margin-bottom: 24px; }
.hero h1 .gold-text { display: inline-block; }
.hero__sub { font-size: 1.12rem; color: var(--text-300); max-width: 58ch; margin-bottom: 38px; }
.hero__cta { display: flex; gap: 16px; flex-wrap: wrap; }
.hero__stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; margin-top: 76px; }
.stat { border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; background: var(--surface); }
.stat__num { font-family: var(--ff-serif); font-size: 2.1rem; color: var(--text-100); line-height: 1; }
.stat__num .gold-text { font-family: var(--ff-serif); }
.stat__label { color: var(--text-300); font-size: 0.86rem; margin-top: 8px; }

/* ---------- 区块标题 ---------- */
.sec-head { max-width: 720px; margin-bottom: 56px; }
.sec-head.center { margin-left: auto; margin-right: auto; }
.sec-tag { color: var(--gold-soft); font-size: 0.82rem; letter-spacing: 0.16em; text-transform: uppercase; display: block; margin-bottom: 14px; }
.sec-head h2 { font-size: clamp(1.8rem, 3.6vw, 2.8rem); margin-bottom: 16px; }
.sec-head p { color: var(--text-300); }

/* ---------- 卡片网格 ---------- */
.grid { display: grid; gap: 22px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  border: 1px solid var(--border); border-radius: var(--radius); padding: 30px; background: var(--grad-surface);
  position: relative; overflow: hidden; transition: transform .35s var(--ease), border-color .35s, box-shadow .35s;
}
.card::before {
  content: ""; position: absolute; inset: 0; background: radial-gradient(420px circle at var(--mx,50%) var(--my,0%), var(--gold-glow), transparent 60%);
  opacity: 0; transition: opacity .4s; pointer-events: none;
}
.card:hover { transform: translateY(-6px); border-color: var(--border-strong); box-shadow: var(--shadow-lg); }
.card:hover::before { opacity: 1; }
.card__icon { width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center; background: var(--surface-2); border: 1px solid var(--border); margin-bottom: 20px; color: var(--gold); }
.card h3 { font-size: 1.22rem; margin-bottom: 12px; }
.card p { color: var(--text-300); font-size: 0.95rem; }
.card__link { margin-top: 18px; display: inline-flex; align-items: center; gap: 6px; color: var(--gold-soft); font-size: 0.9rem; font-weight: 600; }

/* 服务卡 */
.svc-card .svc-no { font-family: var(--ff-serif); color: var(--text-400); font-size: 0.9rem; letter-spacing: .1em; }
.svc-card h3 { margin: 10px 0 12px; }

/* ---------- 流程 ---------- */
.steps { display: grid; grid-template-columns: repeat(5, 1fr); gap: 18px; counter-reset: step; }
.step { border: 1px solid var(--border); border-radius: var(--radius); padding: 26px 22px; background: var(--surface); position: relative; }
.step__no { font-family: var(--ff-serif); font-size: 2.4rem; color: transparent; background: var(--grad-gold); -webkit-background-clip: text; background-clip: text; line-height: 1; }
.step h4 { font-size: 1.05rem; margin: 12px 0 8px; }
.step p { color: var(--text-300); font-size: 0.88rem; }

/* ---------- 双引擎 (SEO/GEO) ---------- */
.engines { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.engine { border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 40px; background: var(--surface); position: relative; overflow: hidden; }
.engine__badge { font-size: 0.78rem; letter-spacing: .15em; color: var(--gold-soft); border: 1px solid var(--border); display: inline-block; padding: 5px 13px; border-radius: 999px; margin-bottom: 18px; }
.engine h3 { font-size: 1.5rem; margin-bottom: 12px; }
.engine ul { margin-top: 18px; display: grid; gap: 12px; }
.engine li { display: flex; gap: 11px; color: var(--text-300); font-size: 0.95rem; }
.engine li svg { flex: 0 0 auto; margin-top: 4px; color: var(--gold); }

/* ---------- 案例 ---------- */
.case-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.case {
  border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; background: var(--bg-700);
  transition: transform .35s var(--ease), box-shadow .35s; position: relative;
}
.case:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.case__visual { aspect-ratio: 16/10; position: relative; overflow: hidden; }
.case__visual svg { width: 100%; height: 100%; }
.case__body { padding: 22px; }
.case__tag { font-size: 0.76rem; color: var(--gold-soft); letter-spacing: .1em; text-transform: uppercase; }
.case__body h3 { font-size: 1.15rem; margin: 8px 0 6px; }
.case__body p { color: var(--text-300); font-size: 0.9rem; }
.case__meta { display: flex; gap: 18px; margin-top: 16px; padding-top: 16px; border-top: 1px solid var(--border); }
.case__meta div span { display: block; }
.case__meta .v { font-family: var(--ff-serif); color: var(--text-100); font-size: 1.15rem; }
.case__meta .k { color: var(--text-400); font-size: 0.76rem; }

/* ---------- FAQ ---------- */
.faq { border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); overflow: hidden; }
.faq__item + .faq__item { border-top: 1px solid var(--border); }
.faq__q { width: 100%; text-align: left; background: none; border: 0; color: var(--text-100); font-family: var(--ff-sans); font-size: 1.02rem; font-weight: 600; padding: 22px 24px; cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.faq__q .ico { flex: 0 0 auto; transition: transform .3s; color: var(--gold); }
.faq__item.open .faq__q .ico { transform: rotate(45deg); }
.faq__a { max-height: 0; overflow: hidden; transition: max-height .35s var(--ease); }
.faq__a-inner { padding: 0 24px 24px; color: var(--text-300); font-size: 0.96rem; }

/* ---------- CTA 区 ---------- */
.cta { border: 1px solid var(--border-strong); border-radius: var(--radius-lg); padding: 64px 48px; text-align: center; background: var(--grad-surface); position: relative; overflow: hidden; }
.cta::before { content: ""; position: absolute; inset: 0; background: radial-gradient(600px circle at 50% -20%, var(--gold-glow), transparent 60%); }
.cta h2 { font-size: clamp(1.8rem, 3.4vw, 2.6rem); margin-bottom: 16px; position: relative; }
.cta p { color: var(--text-300); max-width: 50ch; margin: 0 auto 30px; position: relative; }

/* ---------- 页脚 ---------- */
.footer { border-top: 1px solid var(--border); padding: 64px 0 32px; position: relative; z-index: 1; background: var(--bg-800); }
.footer__grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 40px; }
.footer__brand p { color: var(--text-300); font-size: 0.92rem; max-width: 34ch; margin-top: 16px; }
.footer h4 { font-family: var(--ff-sans); font-size: 0.86rem; letter-spacing: .12em; text-transform: uppercase; color: var(--text-400); margin-bottom: 18px; }
.footer__col a { display: block; color: var(--text-300); font-size: 0.92rem; padding: 6px 0; transition: color .2s; }
.footer__col a:hover { color: var(--gold-soft); }
.footer__bottom { margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--border); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; color: var(--text-400); font-size: 0.84rem; }

/* ---------- 面包屑 ---------- */
.crumbs { padding: calc(var(--nav-h) + 30px) 0 0; color: var(--text-400); font-size: 0.86rem; }
.crumbs a:hover { color: var(--gold-soft); }
.crumbs span { margin: 0 8px; }

/* ---------- 文章 ---------- */
.article { max-width: 760px; margin: 0 auto; }
.article h1 { font-size: clamp(2rem, 4vw, 3rem); margin: 18px 0 14px; }
.article h2 { font-size: 1.6rem; margin: 44px 0 16px; }
.article h3 { font-size: 1.25rem; margin: 30px 0 12px; }
.article p { color: var(--text-200); }
.article blockquote { border-left: 3px solid var(--gold); padding: 6px 0 6px 22px; margin: 28px 0; color: var(--text-100); font-family: var(--ff-serif); font-size: 1.15rem; }
.article ul.ticks { display: grid; gap: 12px; margin: 20px 0; }
.article ul.ticks li { display: flex; gap: 11px; color: var(--text-200); }
.article ul.ticks svg { color: var(--gold); flex: 0 0 auto; margin-top: 5px; }
.meta-row { display: flex; gap: 18px; color: var(--text-400); font-size: 0.88rem; flex-wrap: wrap; }

/* ---------- 联系表单 ---------- */
.form { display: grid; gap: 18px; max-width: 620px; }
.field label { display: block; font-size: 0.88rem; color: var(--text-300); margin-bottom: 8px; }
.field input, .field textarea, .field select {
  width: 100%; background: var(--bg-700); border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 13px 15px; color: var(--text-100); font-family: var(--ff-sans); font-size: 0.95rem; transition: border-color .2s;
}
.field input:focus, .field textarea:focus, .field select:focus { outline: none; border-color: var(--gold); }
.field textarea { min-height: 130px; resize: vertical; }

/* ---------- 滚动揭示动画 ---------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
.reveal[data-delay="1"] { transition-delay: .08s; }
.reveal[data-delay="2"] { transition-delay: .16s; }
.reveal[data-delay="3"] { transition-delay: .24s; }
.reveal[data-delay="4"] { transition-delay: .32s; }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .grid-3, .grid-4, .case-grid, .steps { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .engines { grid-template-columns: 1fr; }
  .footer__grid { grid-template-columns: 1fr 1fr; }
  .hero__stats { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 680px) {
  .nav__links { display: none; }
  .nav__burger { display: flex; }
  .nav__links.open { display: flex; position: absolute; top: var(--nav-h); left: 0; right: 0; flex-direction: column; background: var(--bg-800); padding: 20px 24px; gap: 18px; border-bottom: 1px solid var(--border); }
  .grid-2, .grid-3, .grid-4, .case-grid, .steps, .footer__grid, .hero__stats { grid-template-columns: 1fr; }
  .section { padding: 72px 0; }
  .cta { padding: 44px 24px; }
  .engine { padding: 28px; }
}

/* 打印/无障碍 */
:focus-visible { outline: 2px solid var(--gold); outline-offset: 2px; }
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; }
}