/* =========================================================
   yuanye.world — 设计系统
   东方 · 科技 · 人文 · 可信任
   ========================================================= */

:root {
  /* 墨与纸 */
  --ink:        #16191c;
  --ink-soft:   #3c4248;
  --ink-faint:  #6b7178;
  --paper:      #f6f3ec;
  --paper-2:    #efe9dd;
  --paper-3:    #e7e0d0;
  --card:       #fffdf8;

  /* 东方色 */
  --cinnabar:   #9c2b25;   /* 朱砂红 — 主强调 */
  --cinnabar-d: #7d211c;
  --jade:       #2f5d50;   /* 石青/青瓷 — 次强调 */
  --jade-l:     #e3ece6;
  --gold:       #b08a3e;   /* 赭金 — 高级点缀 */
  --gold-l:     #ecdfc4;

  /* 线 */
  --line:       rgba(22,25,28,0.12);
  --line-soft:  rgba(22,25,28,0.06);
  --line-jade:  rgba(47,93,80,0.22);

  /* 字 */
  --serif: "Noto Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --sans:  "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;

  --maxw: 1180px;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(22,25,28,.04), 0 12px 32px -16px rgba(22,25,28,.22);
  --shadow-l: 0 2px 6px rgba(22,25,28,.06), 0 28px 60px -28px rgba(22,25,28,.30);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.75;
  font-size: 16px;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

/* 宣纸纹理（极淡） */
body::before {
  content: "";
  position: fixed; inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image:
    radial-gradient(circle at 20% 10%, rgba(176,138,62,.05), transparent 40%),
    radial-gradient(circle at 85% 80%, rgba(47,93,80,.05), transparent 45%);
  opacity: .9;
}

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 28px; position: relative; z-index: 1; }

/* ---------- 排版 ---------- */
h1,h2,h3,h4 { font-family: var(--serif); font-weight: 600; line-height: 1.25; color: var(--ink); margin: 0; }
.display { font-size: clamp(38px, 6vw, 76px); letter-spacing: .02em; }
.h2 { font-size: clamp(26px, 3.4vw, 40px); }
.h3 { font-size: clamp(20px, 2.2vw, 26px); }
.lead { font-size: clamp(16px, 1.4vw, 19px); color: var(--ink-soft); }
.muted { color: var(--ink-faint); }

/* 章节标题：竖排标号 + 朱砂 */
.section { padding: clamp(64px, 9vw, 120px) 0; position: relative; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: 13px; letter-spacing: .28em; text-transform: uppercase;
  color: var(--cinnabar); font-weight: 600; margin-bottom: 18px;
}
.eyebrow::before {
  content: ""; width: 26px; height: 1px; background: var(--cinnabar);
}
.sec-head { max-width: 760px; margin-bottom: 52px; }
.sec-head p { margin: 16px 0 0; color: var(--ink-soft); }

/* ---------- 导航 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(246,243,236,.82);
  backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid var(--line-soft);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: baseline; gap: 10px; font-family: var(--serif); }
.brand .cn { font-size: 20px; font-weight: 600; letter-spacing: .04em; }
.brand .en { font-size: 12px; color: var(--ink-faint); letter-spacing: .18em; text-transform: uppercase; font-family: var(--sans); }
.nav-links { display: flex; align-items: center; gap: 30px; }
.nav-links a { font-size: 15px; color: var(--ink-soft); position: relative; padding: 6px 0; transition: color .2s; }
.nav-links a::after {
  content: ""; position: absolute; left: 0; bottom: 0; width: 0; height: 2px;
  background: var(--cinnabar); transition: width .25s ease;
}
.nav-links a:hover, .nav-links a.active { color: var(--ink); }
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }
.nav-cta {
  border: 1px solid var(--ink); border-radius: 999px; padding: 9px 20px !important;
  color: var(--ink) !important; font-weight: 500;
}
.nav-cta::after { display: none; }
.nav-cta:hover { background: var(--ink); color: var(--paper) !important; }
.burger { display: none; flex-direction: column; gap: 5px; cursor: pointer; background: none; border: 0; padding: 8px; }
.burger span { width: 24px; height: 2px; background: var(--ink); border-radius: 2px; transition: .25s; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--sans); font-size: 15px; font-weight: 500;
  padding: 13px 26px; border-radius: 999px; cursor: pointer;
  border: 1px solid transparent; transition: .22s ease; letter-spacing: .02em;
}
.btn-primary { background: var(--ink); color: var(--paper); }
.btn-primary:hover { background: var(--cinnabar-d); transform: translateY(-1px); }
.btn-ghost { border-color: var(--ink); color: var(--ink); background: transparent; }
.btn-ghost:hover { background: var(--ink); color: var(--paper); }
.btn-jade { background: var(--jade); color: #fff; }
.btn-jade:hover { background: #244a40; }
.btn .arr { transition: transform .22s; }
.btn:hover .arr { transform: translateX(4px); }

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

.card {
  background: var(--card); border: 1px solid var(--line-soft);
  border-radius: var(--radius); padding: 30px; box-shadow: var(--shadow);
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
  position: relative; overflow: hidden;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-l); border-color: var(--line-jade); }
.card .k {
  font-family: var(--serif); font-size: 13px; letter-spacing: .2em; color: var(--gold);
  text-transform: uppercase; display: block; margin-bottom: 14px;
}
.card h3 { font-size: 20px; margin-bottom: 10px; }
.card p { margin: 0; color: var(--ink-soft); font-size: 15px; }
.card .tag { display: inline-block; margin-top: 16px; font-size: 13px; color: var(--jade); }
.card .num {
  position: absolute; right: 22px; top: 14px; font-family: var(--serif);
  font-size: 46px; color: var(--paper-3); line-height: 1; font-weight: 600;
}

/* 细描边纹理角标 */
.corner { position: absolute; width: 14px; height: 14px; border: 1.5px solid var(--gold); opacity: .5; }
.corner.tl { left: 12px; top: 12px; border-right: 0; border-bottom: 0; }
.corner.br { right: 12px; bottom: 12px; border-left: 0; border-top: 0; }

/* ---------- Hero ---------- */
.hero { position: relative; padding: clamp(72px, 11vw, 150px) 0 clamp(60px, 8vw, 110px); overflow: hidden; }
.hero-art { position: absolute; inset: 0; z-index: 0; pointer-events: none; }
.hero .wrap { position: relative; z-index: 2; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 10px; font-size: 13px;
  letter-spacing: .16em; color: var(--ink-soft); border: 1px solid var(--line);
  padding: 7px 16px; border-radius: 999px; background: rgba(255,253,248,.6); margin-bottom: 30px;
}
.hero-badge .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--cinnabar); }
.hero h1 { max-width: 14ch; }
.hero h1 .accent { color: var(--cinnabar); }
.hero .sub { max-width: 56ch; margin: 28px 0 14px; font-size: clamp(17px,1.6vw,20px); color: var(--ink-soft); }
.hero .actions { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 16px; }
.hero-stats { display: flex; gap: 44px; margin-top: 56px; flex-wrap: wrap; }
.hero-stats .s b { display: block; font-family: var(--serif); font-size: 34px; color: var(--ink); line-height: 1; }
.hero-stats .s span { font-size: 13px; color: var(--ink-faint); letter-spacing: .08em; }
.hero-stats .s b .u { font-size: 16px; color: var(--cinnabar); margin-left: 2px; }

/* ---------- 分章带 ---------- */
.band { background: var(--ink); color: var(--paper); }
.band .eyebrow { color: var(--gold-l); }
.band .eyebrow::before { background: var(--gold); }
.band h2, .band h3 { color: var(--paper); }
.band p { color: rgba(246,243,236,.72); }

/* ---------- 列表（问题/服务） ---------- */
.feature { display: grid; grid-template-columns: 56px 1fr; gap: 20px; padding: 22px 0; border-top: 1px solid var(--line-soft); }
.feature:last-child { border-bottom: 1px solid var(--line-soft); }
.feature .ic {
  width: 56px; height: 56px; border-radius: 12px; display: grid; place-items: center;
  background: var(--jade-l); color: var(--jade); font-family: var(--serif); font-size: 22px;
}
.feature h3 { font-size: 19px; margin-bottom: 6px; }
.feature p { margin: 0; color: var(--ink-soft); font-size: 15px; }

/* ---------- 标签云 ---------- */
.tags { display: flex; flex-wrap: wrap; gap: 10px; }
.tag-pill {
  font-size: 14px; padding: 8px 16px; border-radius: 999px;
  border: 1px solid var(--line); color: var(--ink-soft); background: var(--card);
  transition: .2s;
}
.tag-pill:hover { border-color: var(--cinnabar); color: var(--cinnabar); }

/* ---------- 时间线（经历） ---------- */
.timeline { position: relative; padding-left: 30px; }
.timeline::before { content: ""; position: absolute; left: 7px; top: 6px; bottom: 6px; width: 1px; background: var(--line); }
.tl-item { position: relative; padding: 0 0 30px 22px; }
.tl-item::before { content: ""; position: absolute; left: -26px; top: 7px; width: 11px; height: 11px; border-radius: 50%; background: var(--paper); border: 2px solid var(--cinnabar); }
.tl-item .yr { font-family: var(--serif); color: var(--cinnabar); font-size: 14px; letter-spacing: .1em; }
.tl-item h3 { font-size: 18px; margin: 4px 0 6px; }
.tl-item p { margin: 0; color: var(--ink-soft); font-size: 15px; }

/* ---------- 页脚 ---------- */
.footer { background: var(--ink); color: var(--paper); padding: 72px 0 36px; position: relative; z-index: 1; }
.footer .grid { align-items: start; }
.footer .f-brand .cn { font-family: var(--serif); font-size: 22px; }
.footer .f-brand .en { color: rgba(246,243,236,.5); font-size: 12px; letter-spacing: .2em; text-transform: uppercase; }
.footer p { color: rgba(246,243,236,.6); font-size: 14px; }
.footer h4 { color: var(--paper); font-size: 15px; margin-bottom: 16px; letter-spacing: .05em; }
.footer ul { list-style: none; padding: 0; margin: 0; }
.footer ul li { margin-bottom: 11px; }
.footer ul a { color: rgba(246,243,236,.72); font-size: 14px; transition: .2s; }
.footer ul a:hover { color: var(--gold-l); }
.footer .bottom { border-top: 1px solid rgba(246,243,236,.12); margin-top: 48px; padding-top: 22px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; font-size: 13px; color: rgba(246,243,236,.45); }
.footer-entry { display: flex; gap: 10px; align-items: center; font-size: 14px; color: rgba(246,243,236,.8); margin-bottom: 12px; }
.footer-entry .e-ic { width: 30px; height: 30px; border-radius: 8px; background: rgba(176,138,62,.18); color: var(--gold-l); display: grid; place-items: center; font-size: 14px; }

/* CTA 横幅 */
.cta-band {
  background: linear-gradient(135deg, var(--jade) 0%, #244a40 100%);
  color: #fff; border-radius: 22px; padding: clamp(40px,6vw,68px);
  position: relative; overflow: hidden;
}
.cta-band h2 { color: #fff; max-width: 18ch; }
.cta-band p { color: rgba(255,255,255,.82); max-width: 52ch; margin: 14px 0 28px; }

/* 表单 */
.form-grid { display: grid; gap: 16px; }
.field label { display: block; font-size: 13px; color: var(--ink-soft); margin-bottom: 7px; letter-spacing: .04em; }
.field input, .field textarea, .field select {
  width: 100%; font-family: var(--sans); font-size: 15px; color: var(--ink);
  background: var(--paper); border: 1px solid var(--line); border-radius: 10px;
  padding: 13px 15px; transition: .2s;
}
.field input:focus, .field textarea:focus, .field select:focus {
  outline: none; border-color: var(--jade); box-shadow: 0 0 0 3px var(--jade-l);
}
.field textarea { min-height: 120px; resize: vertical; }
.form-note { font-size: 13px; color: var(--ink-faint); }
.form-ok { display: none; padding: 16px 18px; border-radius: 10px; background: var(--jade-l); color: var(--jade); font-size: 14px; border: 1px solid var(--line-jade); }
.form-ok.show { display: block; }

/* 工具条提示（演示） */
.demo-flag {
  position: fixed; left: 18px; bottom: 18px; z-index: 60;
  background: rgba(22,25,28,.9); color: var(--paper); font-size: 12px;
  padding: 8px 14px; border-radius: 999px; letter-spacing: .04em;
  display: flex; align-items: center; gap: 8px;
}
.demo-flag .d { width: 7px; height: 7px; border-radius: 50%; background: var(--gold); }

/* 滚动揭示 */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* breadcrumb */
.crumb { font-size: 13px; color: var(--ink-faint); padding: 22px 0 0; letter-spacing: .04em; }
.crumb a:hover { color: var(--cinnabar); }

/* 子站卡片 */
.sub-card {
  display: block; background: var(--card); border: 1px solid var(--line-soft);
  border-radius: var(--radius); padding: 28px; box-shadow: var(--shadow);
  transition: .25s; position: relative; overflow: hidden;
}
.sub-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-l); border-color: var(--line-jade); }
.sub-card .dom { font-family: var(--serif); font-size: 13px; letter-spacing: .12em; color: var(--gold); margin-bottom: 12px; }
.sub-card h3 { font-size: 21px; margin-bottom: 8px; }
.sub-card p { color: var(--ink-soft); font-size: 14px; margin: 0 0 14px; }
.sub-card .go { font-size: 13px; color: var(--jade); display: inline-flex; align-items: center; gap: 6px; }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .cols-4 { grid-template-columns: repeat(2,1fr); }
  .cols-3 { grid-template-columns: repeat(2,1fr); }
}
@media (max-width: 760px) {
  .nav-links {
    position: fixed; inset: 68px 0 auto 0; background: var(--paper);
    flex-direction: column; align-items: stretch; gap: 0; padding: 14px 28px 22px;
    border-bottom: 1px solid var(--line); transform: translateY(-130%); transition: transform .3s ease;
    box-shadow: var(--shadow);
  }
  .nav-links.open { transform: translateY(0); }
  .nav-links a { padding: 13px 0; border-bottom: 1px solid var(--line-soft); }
  .nav-links a::after { display: none; }
  .nav-cta { text-align: center; margin-top: 12px; }
  .burger { display: flex; }
  .cols-2, .cols-3, .cols-4 { grid-template-columns: 1fr; }
  .hero-stats { gap: 28px; }
  .wrap { padding: 0 20px; }
}