/* 彰九云官网 · 全站共享主题（与首页对齐） */
:root {
  --brand: #1890ff;
  --brand-hover: #40a9ff;
  --brand-active: #096dd9;
  --brand-soft: #e6f7ff;
  --brand-muted: rgba(24, 144, 255, 0.08);
  --ink: #262626;
  --body: #434343;
  --muted: #8c8c8c;
  --disabled: #bfbfbf;
  --page: #ffffff;
  --page-bg: #eef2f7;
  --alt: #f7f9fc;
  --card: #ffffff;
  --border: #f0f0f0;
  --border-strong: #e8e8e8;
  --footer: #0f172a;
  --footer-text: rgba(255, 255, 255, 0.65);
  --success: #52c41a;
  --warning: #faad14;
  --danger: #ff4d4f;
  --accent-orange: #fa8c16;
  --max-w: 1200px;
  --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial,
    'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --text-hero: clamp(28px, 4vw, 40px);
  --text-hero-weight: 800;
  --text-h1: 32px;
  --text-h2: 24px;
  --text-h3: 18px;
  --text-body: 15px;
  --text-caption: 13px;
  --radius: 8px;
  --nav-h: 72px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  color: var(--body);
  background: var(--page-bg);
  font-size: var(--text-body);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* ── Nav ── */
.site-nav {
  height: var(--nav-h);
  background: var(--page);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 50;
}
.site-nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  width: 100%;
  display: flex;
  align-items: center;
  gap: 32px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--ink);
  font-weight: 700;
  font-size: 18px;
  flex-shrink: 0;
}
.logo-img { height: 48px; width: auto; display: block; }
.logo-icon { width: 32px; height: 32px; border-radius: 6px; display: block; }
.nav-links {
  display: flex;
  gap: 8px;
  flex: 1;
  flex-wrap: wrap;
}
.nav-links a {
  text-decoration: none;
  color: var(--ink);
  font-size: 14px;
  padding: 8px 14px;
  border-radius: 4px;
  transition: 0.15s;
  font-family: var(--font);
}
.nav-links a:hover { color: var(--brand); background: var(--brand-soft); }
.nav-links a.on { color: var(--brand); background: var(--brand-soft); font-weight: 600; }
.nav-actions { display: flex; gap: 10px; margin-left: auto; align-items: center; }

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  border: none;
  font-family: var(--font);
  transition: 0.15s;
  text-decoration: none;
}
.btn-primary { background: var(--brand); color: #fff; padding: 10px 22px; }
.btn-primary:hover { background: var(--brand-hover); }
.btn-ghost { background: transparent; color: var(--brand); border: 1px solid var(--brand); padding: 8px 18px; }
.btn-ghost:hover { background: var(--brand-soft); }
.btn-text { background: transparent; color: var(--brand); padding: 8px 0; }
.btn-lg { padding: 12px 28px; font-size: var(--text-body); }
.btn-block { width: 100%; }

/* ── Section ── */
.section { padding: 80px 24px; }
.section.alt { background: var(--alt); }
.section-inner { max-width: var(--max-w); margin: 0 auto; }
.section-head {
  text-align: center;
  margin-bottom: 48px;
}
.section-head.left { text-align: left; }
.section-head h2 {
  font-size: var(--text-h1);
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 12px;
  font-family: var(--font);
}
.section-head p {
  color: var(--muted);
  max-width: 640px;
  margin: 0 auto;
  font-size: var(--text-body);
}
.section-head.left p { margin: 0; }
.section-head .line,
.line {
  width: 48px;
  height: 3px;
  background: var(--brand);
  margin: 16px auto 0;
  border-radius: 2px;
}
.section-head.left .line { margin-left: 0; }
.section-label {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--brand);
  text-transform: uppercase;
  margin-bottom: 10px;
  font-family: var(--font);
}

/* ── Footer ── */
.site-footer {
  background: var(--footer);
  color: var(--footer-text);
  padding: 48px 24px 32px;
  text-align: center;
  font-size: var(--text-caption);
  font-family: var(--font);
}
.site-footer a { color: rgba(255, 255, 255, 0.85); text-decoration: none; }
.site-footer a:hover { color: #fff; }
.footer-links { margin-bottom: 16px; display: flex; justify-content: center; gap: 8px; flex-wrap: wrap; }
.footer-links span { opacity: 0.4; }

/* ── 回到顶部（离开首屏后显示） ── */
.site-back-top {
  position: fixed;
  right: 16px;
  bottom: 28px;
  z-index: 85;
  width: 48px;
  height: 48px;
  border: none;
  border-radius: 50%;
  background: var(--brand);
  color: #fff;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 8px 24px rgba(24, 144, 255, 0.35);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity 0.22s ease, transform 0.22s ease, visibility 0.22s ease, background 0.2s ease;
}
.site-back-top.is-visible {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0);
}
.site-back-top:hover {
  background: var(--brand-hover);
}
.site-back-top:focus-visible {
  outline: 2px solid var(--brand-hover);
  outline-offset: 3px;
}
.site-back-top svg {
  width: 22px;
  height: 22px;
  display: block;
  fill: currentColor;
}
@media (prefers-reduced-motion: reduce) {
  .site-back-top {
    transition: none;
    transform: none;
  }
}

/* ── Inner page banner（字阶对齐首页 Hero） ── */
.page-banner,
.about-banner {
  padding: 64px 24px 56px;
  background: linear-gradient(135deg, var(--brand-soft) 0%, var(--page) 55%, var(--alt) 100%);
}
.page-banner-inner,
.about-banner-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  position: relative;
  z-index: 1;
}
.breadcrumb {
  font-size: var(--text-caption);
  color: var(--muted);
  margin-bottom: 20px;
  font-family: var(--font);
}
.breadcrumb a { color: var(--brand); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.page-banner h1,
.about-banner h1 {
  font-size: var(--text-hero);
  font-weight: var(--text-hero-weight);
  line-height: 1.15;
  color: var(--ink);
  margin-bottom: 16px;
  font-family: var(--font);
}
.page-banner h1 em,
.about-banner h1 em {
  font-style: normal;
  color: var(--brand);
}
.page-banner .intro,
.about-banner .intro {
  max-width: 720px;
  font-size: 16px;
  color: var(--body);
  margin-bottom: 28px;
  line-height: 1.7;
  font-family: var(--font);
}
.page-banner .actions { display: flex; gap: 12px; flex-wrap: wrap; }

/* ── CTA band ── */
.cta-band {
  background: var(--brand);
  color: #fff;
  text-align: center;
  padding: 64px 24px;
  font-family: var(--font);
}
.cta-band h2 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 12px;
  font-family: var(--font);
}
.cta-band p {
  opacity: 0.9;
  margin-bottom: 24px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}
.cta-band .btn { background: #fff; color: var(--brand); }
.cta-band .btn:hover { background: var(--brand-soft); }

@media (max-width: 900px) {
  .section { padding: 56px 16px; }
  .section-head h2 { font-size: 24px; }
  .page-banner h1,
  .about-banner h1 { font-size: clamp(26px, 6vw, 28px); }
}