/* ============================================================
   哈希流光科技官网 全站样式
   设计语言：中式现代商务 —— 藏蓝主色 + 朱砂点缀 + 米白底
   无外部字体/CDN 依赖，保证大陆访问速度与 LCP ≤ 2.5s
   ============================================================ */

:root {
  --ink: #1c2434;            /* 墨色正文 */
  --ink-light: #5a6478;      /* 次级文字 */
  --navy: #22386b;           /* 藏蓝主色 */
  --navy-deep: #182a52;      /* 深藏蓝 */
  --vermilion: #c53d2a;      /* 朱砂红点缀 */
  --gold: #b8925a;           /* 鎏金 */
  --bg: #f7f6f2;             /* 米白底 */
  --card: #ffffff;
  --line: #e5e2da;
  --radius: 10px;
  --shadow: 0 2px 14px rgba(28, 36, 52, 0.07);
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }

a { color: var(--navy); text-decoration: none; }
a:hover { color: var(--vermilion); }

.container { max-width: 1120px; margin: 0 auto; padding: 0 24px; }

/* ---------- 顶部导航 ---------- */
.site-header {
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-mark {
  width: 40px;
  height: 40px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-deep) 100%);
  color: #fff;
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  letter-spacing: 1px;
}

.brand-name {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 2px;
}

.brand-sub {
  font-size: 12px;
  color: var(--ink-light);
  letter-spacing: 1px;
  display: block;
  line-height: 1.3;
}

.main-nav ul {
  display: flex;
  list-style: none;
  gap: 6px;
}

.main-nav a {
  display: block;
  padding: 8px 16px;
  font-size: 15px;
  color: var(--ink);
  border-radius: 6px;
  transition: all 0.2s;
}

.main-nav a:hover { background: #f0eee8; color: var(--navy); }

.main-nav a.active {
  color: var(--vermilion);
  font-weight: 600;
}

.nav-toggle { display: none; }

/* ---------- Hero 首屏 ---------- */
.hero {
  background:
    radial-gradient(ellipse 80% 60% at 85% 20%, rgba(184, 146, 90, 0.16), transparent),
    radial-gradient(ellipse 70% 70% at 10% 90%, rgba(197, 61, 42, 0.10), transparent),
    linear-gradient(160deg, #1b2c56 0%, #22386b 55%, #2b4680 100%);
  color: #fff;
  padding: 84px 0 76px;
  position: relative;
  overflow: hidden;
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 44px 44px;
  pointer-events: none;
}

.hero .container { position: relative; z-index: 1; }

.hero-tag {
  display: inline-block;
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: 100px;
  padding: 5px 18px;
  font-size: 13px;
  letter-spacing: 3px;
  margin-bottom: 26px;
  color: #e8dcc3;
}

.hero h1 {
  font-family: var(--font-serif);
  font-size: 42px;
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: 2px;
  margin-bottom: 18px;
}

.hero h1 em {
  font-style: normal;
  color: #e8c98f;
}

.hero-lead {
  font-size: 17px;
  max-width: 720px;
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 36px;
}

.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }

.btn {
  display: inline-block;
  padding: 12px 32px;
  border-radius: 6px;
  font-size: 16px;
  letter-spacing: 1px;
  transition: all 0.2s;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--vermilion);
  color: #fff;
}
.btn-primary:hover { background: #a83222; color: #fff; }

.btn-ghost {
  border-color: rgba(255, 255, 255, 0.5);
  color: #fff;
}
.btn-ghost:hover { background: rgba(255, 255, 255, 0.12); color: #fff; }

.hero-facts {
  display: flex;
  gap: 48px;
  margin-top: 52px;
  flex-wrap: wrap;
}

.hero-facts .fact strong {
  display: block;
  font-family: var(--font-serif);
  font-size: 30px;
  color: #e8c98f;
}

.hero-facts .fact span { font-size: 14px; color: rgba(255,255,255,0.75); }

/* ---------- 页面头（内页） ---------- */
.page-head {
  background: linear-gradient(160deg, #1b2c56 0%, #22386b 70%);
  color: #fff;
  padding: 52px 0 44px;
}

.page-head h1 {
  font-family: var(--font-serif);
  font-size: 32px;
  letter-spacing: 2px;
  margin-bottom: 10px;
}

.page-head .page-lead {
  max-width: 820px;
  color: rgba(255, 255, 255, 0.88);
  font-size: 16px;
}

.breadcrumb {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.65);
  margin-bottom: 16px;
}
.breadcrumb a { color: rgba(255, 255, 255, 0.85); }

/* ---------- 通用区块 ---------- */
.section { padding: 64px 0; }

.section-alt { background: #fdfcfa; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }

.section-title {
  text-align: center;
  margin-bottom: 44px;
}

.section-title .cn {
  font-family: var(--font-serif);
  font-size: 30px;
  font-weight: 700;
  letter-spacing: 3px;
  color: var(--ink);
  display: block;
}

.section-title .cn::after {
  content: "";
  display: block;
  width: 44px;
  height: 3px;
  background: var(--vermilion);
  margin: 14px auto 0;
  border-radius: 2px;
}

.section-title .desc {
  margin-top: 16px;
  color: var(--ink-light);
  font-size: 15px;
  max-width: 760px;
  margin-left: auto;
  margin-right: auto;
}

/* 更新时间标注（GEO 时效标记） */
.meta-dates {
  font-size: 13px;
  color: var(--ink-light);
  text-align: center;
  margin-top: -30px;
  margin-bottom: 36px;
}

.page-meta-dates {
  font-size: 13px;
  color: rgba(255,255,255,0.6);
  margin-top: 14px;
}

/* ---------- 卡片栅格 ---------- */
.grid { display: grid; gap: 24px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 28px;
  box-shadow: var(--shadow);
  transition: transform 0.2s, box-shadow 0.2s;
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(28, 36, 52, 0.11);
}

.card .card-icon {
  width: 48px;
  height: 48px;
  border-radius: 10px;
  background: #eef1f8;
  color: var(--navy);
  font-size: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}

.card h3 {
  font-family: var(--font-serif);
  font-size: 19px;
  margin-bottom: 10px;
  color: var(--ink);
}

.card p, .card li { font-size: 14.5px; color: var(--ink-light); }

.card ul { list-style: none; margin-top: 10px; }

.card ul li {
  padding-left: 18px;
  position: relative;
  margin-bottom: 6px;
}

.card ul li::before {
  content: "·";
  position: absolute;
  left: 4px;
  color: var(--vermilion);
  font-weight: 700;
}

/* ---------- 正文文章排版 ---------- */
.prose h2 {
  font-family: var(--font-serif);
  font-size: 24px;
  margin: 44px 0 18px;
  padding-left: 14px;
  border-left: 4px solid var(--vermilion);
  color: var(--ink);
}

.prose h2:first-child { margin-top: 0; }

.prose h3 {
  font-size: 18px;
  margin: 28px 0 12px;
  color: var(--navy);
}

.prose p { margin-bottom: 14px; color: #333c4e; }

.prose ul, .prose ol { margin: 0 0 16px 24px; color: #333c4e; }

.prose li { margin-bottom: 8px; }

.prose strong { color: var(--ink); }

/* 标准答案框（GEO 首段直接可摘录答案） */
.answer-box {
  background: #f4f6fb;
  border: 1px solid #d8deee;
  border-left: 4px solid var(--navy);
  border-radius: 8px;
  padding: 18px 22px;
  margin-bottom: 28px;
  font-size: 15.5px;
  color: var(--ink);
}

.answer-box .label {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: #fff;
  background: var(--navy);
  border-radius: 4px;
  padding: 1px 8px;
  margin-right: 8px;
  vertical-align: 2px;
}

/* ---------- 表格 ---------- */
.table-wrap { overflow-x: auto; margin: 20px 0; }

table.data {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  font-size: 14.5px;
}

table.data th {
  background: var(--navy);
  color: #fff;
  font-weight: 600;
  padding: 12px 16px;
  text-align: left;
  letter-spacing: 1px;
}

table.data td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  color: #333c4e;
  vertical-align: top;
}

table.data tr:nth-child(even) td { background: #faf9f6; }

/* ---------- 案例 ---------- */
.case-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 30px 26px;
  box-shadow: var(--shadow);
  margin-bottom: 26px;
}

.case-card .case-tag {
  display: inline-block;
  font-size: 12.5px;
  color: var(--vermilion);
  background: #faeae7;
  border-radius: 4px;
  padding: 2px 10px;
  margin-bottom: 12px;
  margin-right: 8px;
}

.case-card h3 {
  font-family: var(--font-serif);
  font-size: 20px;
  margin-bottom: 14px;
}

.case-card dl { margin: 0; }

.case-card dt {
  font-weight: 600;
  color: var(--navy);
  margin-top: 12px;
  font-size: 14.5px;
}

.case-card dd {
  margin-left: 0;
  color: #333c4e;
  font-size: 14.5px;
}

.case-metrics {
  display: flex;
  gap: 36px;
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px dashed var(--line);
  flex-wrap: wrap;
}

.case-metrics .m strong {
  display: block;
  font-family: var(--font-serif);
  font-size: 24px;
  color: var(--vermilion);
}

.case-metrics .m span { font-size: 13px; color: var(--ink-light); }

.case-note {
  font-size: 13px;
  color: var(--ink-light);
  background: #faf9f6;
  border: 1px dashed var(--line);
  border-radius: 8px;
  padding: 12px 18px;
  margin-bottom: 30px;
}

/* ---------- FAQ ---------- */
.faq-group { max-width: 860px; margin: 0 auto; }

details.faq-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 8px;
  margin-bottom: 14px;
  overflow: hidden;
}

details.faq-item summary {
  cursor: pointer;
  padding: 16px 22px;
  font-weight: 600;
  font-size: 16px;
  color: var(--ink);
  list-style: none;
  position: relative;
  padding-right: 46px;
}

details.faq-item summary::-webkit-details-marker { display: none; }

details.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 22px;
  color: var(--gold);
  font-weight: 400;
}

details.faq-item[open] summary::after { content: "−"; }

details.faq-item[open] summary { border-bottom: 1px solid var(--line); color: var(--navy); }

details.faq-item .faq-a {
  padding: 16px 22px;
  font-size: 15px;
  color: #333c4e;
  background: #fdfcfa;
}

.faq-cat-title {
  font-family: var(--font-serif);
  font-size: 20px;
  color: var(--navy);
  margin: 36px 0 16px;
  padding-left: 12px;
  border-left: 4px solid var(--gold);
}

/* ---------- 流程 ---------- */
.steps { counter-reset: step; display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }

.step {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 22px;
  position: relative;
}

.step::before {
  counter-increment: step;
  content: "0" counter(step);
  font-family: var(--font-serif);
  font-size: 34px;
  font-weight: 700;
  color: #e9e4d8;
  display: block;
  margin-bottom: 8px;
  line-height: 1;
}

.step h4 { font-size: 16px; margin-bottom: 8px; color: var(--ink); }

.step p { font-size: 13.5px; color: var(--ink-light); }

/* ---------- 联系 ---------- */
.contact-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 32px; align-items: start; }

.contact-list { list-style: none; }

.contact-list li {
  display: flex;
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px dashed var(--line);
  font-size: 15px;
}

.contact-list .k {
  flex: 0 0 92px;
  color: var(--ink-light);
  font-weight: 600;
}

.contact-list .v { color: var(--ink); }

.qr-row { display: flex; gap: 24px; flex-wrap: wrap; }

.qr-box {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  text-align: center;
  box-shadow: var(--shadow);
  flex: 1;
  min-width: 200px;
}

.qr-box img {
  width: 180px;
  height: auto;
  margin: 0 auto 12px;
  border-radius: 6px;
}

.qr-box .qr-label { font-size: 14.5px; font-weight: 600; color: var(--ink); }

.qr-box .qr-sub { font-size: 12.5px; color: var(--ink-light); margin-top: 4px; }

/* ---------- CTA 横幅 ---------- */
.cta-band {
  background: linear-gradient(135deg, var(--navy-deep), var(--navy));
  color: #fff;
  border-radius: 14px;
  padding: 44px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  flex-wrap: wrap;
}

.cta-band h2 {
  font-family: var(--font-serif);
  font-size: 26px;
  letter-spacing: 2px;
  margin-bottom: 8px;
}

.cta-band p { color: rgba(255,255,255,0.82); font-size: 15px; }

/* ---------- 参考资料（GEO 溯源板块） ---------- */
.refs {
  background: #fdfcfa;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-top: 44px;
  font-size: 14px;
}

.refs h2 {
  font-size: 17px;
  font-family: var(--font-serif);
  margin-bottom: 12px;
  color: var(--ink);
  border: none;
  padding: 0;
}

.refs ol { margin-left: 20px; color: var(--ink-light); }

.refs li { margin-bottom: 6px; }

/* ---------- 页脚 ---------- */
.site-footer {
  background: #16223f;
  color: rgba(255, 255, 255, 0.78);
  padding: 52px 0 0;
  margin-top: 72px;
  font-size: 14px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 36px;
  padding-bottom: 40px;
}

.footer-grid h4 {
  color: #fff;
  font-size: 15.5px;
  margin-bottom: 16px;
  font-family: var(--font-serif);
  letter-spacing: 2px;
}

.footer-grid ul { list-style: none; }

.footer-grid li { margin-bottom: 9px; }

.footer-grid a { color: rgba(255, 255, 255, 0.72); }
.footer-grid a:hover { color: #e8c98f; }

.footer-brand-name {
  font-family: var(--font-serif);
  font-size: 19px;
  color: #fff;
  letter-spacing: 2px;
  margin-bottom: 12px;
}

.footer-qr { display: flex; gap: 16px; }

.footer-qr figure { text-align: center; }

.footer-qr img {
  width: 96px;
  height: auto;
  border-radius: 6px;
  background: #fff;
  padding: 4px;
}

.footer-qr figcaption { font-size: 12px; margin-top: 6px; color: rgba(255,255,255,0.65); }

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding: 18px 0;
  font-size: 12.5px;
  color: rgba(255, 255, 255, 0.5);
  text-align: center;
  line-height: 2;
}

.footer-bottom a { color: rgba(255, 255, 255, 0.6); }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 34px; }
}

@media (max-width: 680px) {
  .grid-3, .grid-2, .steps { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero { padding: 56px 0 48px; }
  .hero h1 { font-size: 27px; }
  .hero-facts { gap: 28px; }
  .section { padding: 44px 0; }
  .cta-band { padding: 32px 26px; }

  .nav-toggle {
    display: block;
    background: none;
    border: 1px solid var(--line);
    border-radius: 6px;
    padding: 6px 12px;
    font-size: 18px;
    color: var(--ink);
    cursor: pointer;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 10px 24px rgba(0,0,0,0.08);
  }

  .main-nav.open { display: block; }

  .main-nav ul { flex-direction: column; padding: 10px 16px; }

  .main-nav a { padding: 12px 10px; }
}