:root {
  --bg: #ffffff;
  --bg-alt: #f6f5f2;
  --ink: #0a0a0a;
  --muted: #6b6b6b;
  --line: #e6e4df;
  --accent: #b8893b;        /* 沉稳金，股权/金融质感 */
  --accent-ink: #8a6418;
  --max: 1080px;
  --radius: 14px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }

/* 导航 */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav__brand {
  font-weight: 800;
  font-size: 18px;
  letter-spacing: 0.02em;
}
.nav__links {
  display: flex;
  align-items: center;
  gap: 22px;
  font-size: 15px;
}
.nav__links a { color: var(--muted); transition: color 0.2s; }
.nav__links a:hover { color: var(--ink); }
.nav__cta {
  color: var(--ink) !important;
  border: 1px solid var(--ink);
  padding: 7px 16px;
  border-radius: 999px;
  font-weight: 600;
}
.nav__cta:hover { background: var(--ink); color: #fff !important; }

/* HERO */
.hero {
  max-width: var(--max);
  margin: 0 auto;
  padding: 72px 24px 64px;
}
.hero__inner {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
}
.hero__eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.22em;
  font-size: 12px;
  color: var(--accent-ink);
  font-weight: 700;
  margin-bottom: 24px;
}
.hero__title {
  font-size: clamp(46px, 8vw, 104px);
  font-weight: 900;
  line-height: 0.98;
  letter-spacing: -0.02em;
}
.hero__sub {
  display: block;
  font-size: clamp(18px, 3.5vw, 30px);
  font-weight: 600;
  color: var(--muted);
  letter-spacing: 0.04em;
  margin-top: 18px;
}
.hero__lead {
  font-size: clamp(19px, 2.6vw, 27px);
  font-weight: 600;
  margin: 32px 0 0;
  max-width: 560px;
}
.hero__actions {
  margin-top: 36px;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}
.hero__media img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.18);
}

/* 按钮 */
.btn {
  display: inline-block;
  padding: 14px 30px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 16px;
  transition: transform 0.15s, background 0.2s, color 0.2s;
}
.btn--primary { background: var(--ink); color: #fff; }
.btn--primary:hover { transform: translateY(-2px); background: #000; }
.btn--ghost { border: 1px solid var(--ink); color: var(--ink); }
.btn--ghost:hover { background: var(--ink); color: #fff; }

/* 区块 */
.section {
  max-width: var(--max);
  margin: 0 auto;
  padding: 84px 24px;
}
.section--alt { background: var(--bg-alt); max-width: none; }
.section--alt > * { max-width: var(--max); margin-left: auto; margin-right: auto; }
.section__kicker {
  text-transform: uppercase;
  letter-spacing: 0.2em;
  font-size: 12px;
  font-weight: 700;
  color: var(--accent-ink);
  margin-bottom: 14px;
}
.section__title {
  font-size: clamp(30px, 5vw, 48px);
  font-weight: 850;
  letter-spacing: -0.01em;
  line-height: 1.1;
  margin-bottom: 36px;
}

/* 图文分栏（关于我等） */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
}
.split__media img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius);
  box-shadow: 0 18px 46px rgba(0, 0, 0, 0.14);
}

/* 正文 */
.prose p { font-size: 18px; margin-bottom: 18px; max-width: 760px; }
.muted { color: var(--muted); font-size: 14px; }

/* 网格卡片 */
.grid { display: grid; gap: 20px; }
.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  background: var(--bg);
  transition: transform 0.18s, box-shadow 0.18s, border-color 0.18s;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 12px 30px rgba(0,0,0,0.06); border-color: var(--accent); }
.card h3 { font-size: 20px; font-weight: 800; margin-bottom: 10px; }
.card p { color: var(--muted); font-size: 15px; }
.card--case .case__tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: var(--accent-ink);
  border: 1px solid var(--accent);
  border-radius: 999px;
  padding: 3px 12px;
  margin-bottom: 14px;
}

/* FAQ */
.faq { max-width: 820px; }
.faq details {
  border-top: 1px solid var(--line);
  padding: 20px 0;
}
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary {
  font-size: 19px;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-size: 24px; color: var(--accent); }
.faq details[open] summary::after { content: "−"; }
.faq p { color: var(--muted); margin-top: 12px; font-size: 16px; }

/* 文章 */
.post {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  display: block;
  transition: transform 0.18s, border-color 0.18s;
}
.post:hover { transform: translateY(-4px); border-color: var(--accent); }
.post__date { font-size: 13px; color: var(--accent-ink); font-weight: 700; }
.post h3 { font-size: 22px; font-weight: 800; margin: 10px 0; }
.post p { color: var(--muted); font-size: 15px; }

/* 联系 — 深色精英 CTA 背景 */
.section--contact {
  position: relative;
  color: #fff;
  text-align: center;
  max-width: none;
  background-image: linear-gradient(rgba(8, 8, 8, 0.74), rgba(8, 8, 8, 0.82)),
    url("./images/cta.png");
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
}
.contact__inner { max-width: var(--max); margin: 0 auto; position: relative; z-index: 1; }
.section--contact .section__kicker { color: var(--accent); }
.section--contact .section__title { color: #fff; }
.section--contact .contact__lead { color: rgba(255, 255, 255, 0.82); }
.contact__lead { font-size: 18px; margin-bottom: 28px; }
.contact__list {
  list-style: none;
  max-width: 520px;
  margin: 0 auto 32px;
  text-align: left;
  font-size: 16px;
}
.contact__list li { padding: 10px 0; border-bottom: 1px solid rgba(255, 255, 255, 0.18); color: rgba(255, 255, 255, 0.88); }
.contact__list a { color: var(--accent); font-weight: 600; }
.section--contact .btn--primary { background: #fff; color: var(--ink); }
.section--contact .btn--primary:hover { background: var(--accent); color: #fff; }

/* 页脚 */
.footer {
  max-width: var(--max);
  margin: 0 auto;
  padding: 40px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--line);
  font-size: 14px;
  color: var(--muted);
}
.footer a { color: var(--ink); font-weight: 600; }

/* 品牌色块（公司标识） */
.brand-tile {
  width: 68px; height: 68px; border-radius: 16px;
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 900; font-size: 30px; color: #fff; line-height: 1;
  background: linear-gradient(135deg, var(--brand, #333), var(--brand2, #666));
  box-shadow: 0 8px 22px rgba(0, 0, 0, 0.16);
  letter-spacing: -0.02em; flex: none;
}
.brand-tile--sm { width: 46px; height: 46px; border-radius: 12px; font-size: 20px; box-shadow: 0 5px 14px rgba(0, 0, 0, 0.14); }

/* 文章页顶部品牌 */
.article-brand { display: flex; align-items: center; gap: 16px; margin-bottom: 18px; }
.article-brand__name { font-weight: 700; font-size: 16px; color: var(--muted); }

/* 文章卡片品牌行 */
.post__brand { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.post__cat { font-size: 12px; font-weight: 700; color: var(--accent-ink); border: 1px solid var(--accent); border-radius: 999px; padding: 3px 10px; }

/* 四大框架卡片（可点击筛选） */
.framework-grid { margin-bottom: 8px; }
.framework-card {
  text-align: left; cursor: pointer; border: 1px solid var(--line);
  border-radius: var(--radius); padding: 26px; background: var(--bg);
  transition: transform 0.18s, border-color 0.18s, box-shadow 0.18s; font-family: inherit;
}
.framework-card:hover { transform: translateY(-4px); border-color: var(--accent); box-shadow: 0 12px 30px rgba(0, 0, 0, 0.06); }
.framework-card__no { font-size: 12px; font-weight: 800; letter-spacing: 0.12em; color: var(--accent-ink); text-transform: uppercase; }
.framework-card h3 { font-size: 22px; font-weight: 800; margin: 8px 0 10px; }
.framework-card p { color: var(--muted); font-size: 14px; line-height: 1.6; }
.framework-card__go { display: inline-block; margin-top: 14px; font-size: 14px; font-weight: 700; color: var(--ink); }

/* 分类筛选 tab */
.filter-bar { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 40px; }
.filter-tab {
  font-family: inherit; cursor: pointer; font-size: 14px; font-weight: 600;
  border: 1px solid var(--line); background: var(--bg); color: var(--muted);
  padding: 9px 18px; border-radius: 999px; transition: all 0.18s;
}
.filter-tab:hover { color: var(--ink); border-color: var(--ink); }
.filter-tab.is-active { background: var(--ink); color: #fff; border-color: var(--ink); }

/* 首页 500强 入口（深色金质感，置于关于我下方） */
.fortune-promo {
  position: relative; max-width: none; color: #fff;
  background: linear-gradient(135deg, #0a0a0a 0%, #16130c 55%, #0a0a0a 100%);
  overflow: hidden;
}
.fortune-promo::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(900px 420px at 85% -10%, rgba(184, 137, 59, 0.22), transparent 60%);
  pointer-events: none;
}
.fortune-promo__inner {
  max-width: var(--max); margin: 0 auto; padding: 72px 24px; position: relative; z-index: 1;
  display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 48px; align-items: center;
}
.fortune-promo .section__kicker { color: var(--accent); }
.fortune-promo .section__title { color: #fff; }
.fortune-promo p { color: rgba(255, 255, 255, 0.82); font-size: 18px; max-width: 560px; margin: 16px 0 28px; }
.fortune-promo .btn--primary { background: var(--accent); color: #1a1206; }
.fortune-promo .btn--primary:hover { background: #d8a85a; }
.fortune-promo__logos { display: flex; flex-wrap: wrap; gap: 14px; justify-content: flex-end; }
.fortune-promo__logos .brand-tile { width: 54px; height: 54px; font-size: 22px; border-radius: 13px; opacity: 0.96; }

/* 移动端汉堡按钮（桌面隐藏） */
.nav__toggle {
  display: none; background: none; border: 0; cursor: pointer;
  font-size: 26px; line-height: 1; color: var(--ink); padding: 4px 6px;
}

/* 响应式 */
@media (max-width: 860px) {
  .grid--3 { grid-template-columns: 1fr; }
  .grid--2 { grid-template-columns: 1fr; }
  .section { padding: 60px 20px; }
  .hero { padding: 64px 20px 48px; }
  .hero__inner { grid-template-columns: 1fr; gap: 32px; }
  .hero__media { order: -1; }
  .split { grid-template-columns: 1fr; gap: 32px; }
  .split__media { order: -1; }
  .section--contact { background-attachment: scroll; }

  /* 移动端汉堡菜单（仅作用于首页导航） */
  .nav__toggle { display: block; }
  #navMenu {
    position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    padding: 6px 20px 14px; display: none;
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.08);
  }
  #navMenu.open { display: flex; }
  #navMenu a { padding: 13px 0; width: 100%; font-size: 16px; border-bottom: 1px solid var(--line); color: var(--ink); }
  #navMenu a:last-child { border-bottom: 0; }
  #navMenu .nav__cta { border: 1px solid var(--ink) !important; text-align: center; margin-top: 8px; }

  /* 首页 500强 入口堆叠 */
  .fortune-promo__inner { grid-template-columns: 1fr; gap: 32px; }
  .fortune-promo__logos { justify-content: flex-start; }
}