/* =========================================================
   中墨通 公共样式：设计变量 / 重置 / 布局 / 按钮 / 头部 / 底部
   所有页面共用，页面专属样式放在各自的 css 文件里
   ========================================================= */

:root {
  /* 品牌色取自 ZMT 标志与公司简介 */
  --navy-900: #061634;
  --navy-800: #0A2250;
  --navy-700: #13306A;
  --blue: #1F4FB4;
  --blue-hover: #1A43A0;
  --blue-soft: #EAF0FB;
  --red: #D9262E;
  --amber: #F2A900;
  --green: #1E9E6A;

  --text: #0F1B33;
  --text-muted: #5B6782;
  --text-faint: #8B95AB;
  --bg: #FFFFFF;
  --bg-soft: #F5F7FB;
  --border: #E2E7F0;

  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 20px;
  --shadow: 0 24px 60px rgba(6, 22, 52, 0.18);
  --shadow-sm: 0 8px 24px rgba(6, 22, 52, 0.06);

  --container: 1200px;
  --gutter: 24px;
  --header-h: 72px;
  --section-y: 96px;

  --font: -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Noto Sans SC', 'Segoe UI', sans-serif;
}

/* ===== Reset ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: var(--header-h); }
body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button, input, select, textarea { font: inherit; color: inherit; }

.icon { width: 24px; height: 24px; flex-shrink: 0; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

/* ===== Layout ===== */
.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
}
.section { padding: var(--section-y) 0; }
.section--soft { background: var(--bg-soft); }
.section--dark { background: var(--navy-900); color: #fff; }

.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }

/* ===== Section heading ===== */
.section-head { max-width: 760px; margin-bottom: 48px; }
.section-head--center { margin-left: auto; margin-right: auto; text-align: center; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  margin-bottom: 14px;
  font-size: 13px; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase;
  color: var(--blue);
}
.eyebrow::before { content: ""; width: 24px; height: 3px; border-radius: 2px; background: var(--red); }
.section--dark .eyebrow { color: #9DB6EC; }
.section-title {
  font-size: clamp(26px, 3.2vw, 38px);
  font-weight: 800; line-height: 1.25; letter-spacing: -0.5px;
}
.section-desc { margin-top: 14px; font-size: 16px; line-height: 1.8; color: var(--text-muted); }
.section--dark .section-desc { color: rgba(255, 255, 255, 0.7); }

.footnote { margin-top: 24px; font-size: 12px; line-height: 1.7; color: var(--text-faint); }
.section--dark .footnote { color: rgba(255, 255, 255, 0.45); }

/* ===== Buttons ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 48px; padding: 0 26px;
  border: 1.5px solid transparent; border-radius: var(--radius-sm);
  font-size: 15px; font-weight: 600; white-space: nowrap;
  cursor: pointer; transition: background 0.2s, border-color 0.2s, color 0.2s;
}
.btn .icon { width: 18px; height: 18px; }
.btn--sm { height: 40px; padding: 0 18px; font-size: 14px; }
.btn--lg { height: 54px; padding: 0 30px; font-size: 16px; }
.btn--primary { background: var(--red); color: #fff; }
.btn--primary:hover { background: #BF1F27; }
.btn--blue { background: var(--blue); color: #fff; }
.btn--blue:hover { background: var(--blue-hover); }
.btn--outline { border-color: var(--border); color: var(--text); background: #fff; }
.btn--outline:hover { border-color: var(--blue); color: var(--blue); }
.btn--ghost-light { border-color: rgba(255, 255, 255, 0.3); color: #fff; }
.btn--ghost-light:hover { border-color: #fff; }

/* ===== Card ===== */
.card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}

/* ===== Header ===== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.site-header__inner { height: var(--header-h); display: flex; align-items: center; gap: 40px; }

.brand { display: flex; align-items: center; gap: 10px; }
.brand img { height: 36px; width: auto; }
.brand__text { display: flex; flex-direction: column; line-height: 1.15; }
.brand__name { font-size: 17px; font-weight: 800; color: var(--navy-800); letter-spacing: 0.02em; }
.brand__sub { font-size: 10px; font-weight: 600; letter-spacing: 0.14em; color: var(--text-faint); }

.site-nav { flex: 1; }
.site-nav ul { display: flex; justify-content: center; gap: 32px; }
.site-nav a { font-size: 15px; font-weight: 500; color: var(--text); transition: color 0.2s; }
.site-nav a:hover { color: var(--blue); }
.site-nav__cta { display: none; }
.header-actions { display: flex; align-items: center; gap: 12px; }
.header-phone { display: inline-flex; align-items: center; gap: 6px; font-size: 14px; font-weight: 600; color: var(--navy-800); }
.header-phone .icon { width: 18px; height: 18px; color: var(--blue); }

.nav-toggle {
  display: none;
  width: 36px; height: 36px; margin-right: -8px;
  align-items: center; justify-content: center;
  border: 0; background: transparent; cursor: pointer;
}
.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  display: block; width: 18px; height: 2px; background: var(--navy-800);
  border-radius: 2px; position: relative; transition: transform 0.2s, background 0.2s;
}
.nav-toggle span::before,
.nav-toggle span::after { content: ""; position: absolute; left: 0; }
.nav-toggle span::before { top: -6px; }
.nav-toggle span::after { top: 6px; }
.nav-toggle[aria-expanded="true"] span { background: transparent; }
.nav-toggle[aria-expanded="true"] span::before { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span::after { transform: translateY(-6px) rotate(-45deg); }

/* ===== Footer ===== */
.site-footer { background: var(--navy-900); color: rgba(255, 255, 255, 0.7); }
.site-footer__top {
  display: grid; grid-template-columns: 1.6fr 1fr 1.4fr; gap: 48px;
  padding: 64px 0 48px;
}
.footer-brand .brand__name { color: #fff; }
.footer-brand .brand__sub { color: rgba(255, 255, 255, 0.5); }
.footer-brand .brand img { background: #fff; border-radius: 6px; padding: 3px 5px; height: 40px; }
.footer-brand p { max-width: 340px; margin-top: 18px; font-size: 14px; line-height: 1.8; }
.footer-col h4 { margin-bottom: 16px; font-size: 14px; font-weight: 700; color: #fff; }
.footer-col li + li { margin-top: 10px; }
.footer-col a,
.footer-col span { font-size: 14px; line-height: 1.7; }
.footer-col a:hover { color: #fff; }
.footer-col small { display: block; font-size: 12px; color: rgba(255, 255, 255, 0.45); }
.site-footer__bottom {
  display: flex; justify-content: space-between; gap: 16px;
  padding: 24px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  font-size: 13px; color: rgba(255, 255, 255, 0.45);
}

/* ===== Responsive ===== */
@media (max-width: 1080px) {
  .header-phone { display: none; }
  .site-nav ul { gap: 24px; }
}

@media (max-width: 960px) {
  :root { --section-y: 72px; }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }

  .site-header__inner { justify-content: space-between; }
  .site-nav {
    display: none;
    position: absolute; top: var(--header-h); left: 0; right: 0;
    padding: 4px var(--gutter) 20px;
    background: var(--bg); border-bottom: 1px solid var(--border);
    box-shadow: 0 12px 24px rgba(6, 22, 52, 0.08);
  }
  .site-nav.is-open { display: block; }
  .site-nav ul { flex-direction: column; gap: 0; }
  .site-nav a { display: block; padding: 14px 0; font-size: 16px; border-bottom: 1px solid var(--border); }
  .site-nav .site-nav__cta { display: flex; width: 100%; margin-top: 16px; border: 0; color: #fff; }
  .header-cta { display: none; }
  .nav-toggle { display: inline-flex; }

  .site-footer__top { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  :root { --gutter: 20px; --section-y: 56px; --header-h: 60px; }
  .grid-3 { grid-template-columns: 1fr; }
  .section-head { margin-bottom: 32px; }
  .brand img { height: 30px; }
  .brand__name { font-size: 15px; }
  .brand__sub { font-size: 9px; }

  .site-footer__top { grid-template-columns: 1fr; gap: 28px; padding: 40px 0 28px; }
  .footer-brand p { max-width: none; font-size: 13px; }
  .footer-col h4 { margin-bottom: 12px; }
  .footer-col li + li { margin-top: 8px; }
  .footer-col--nav ul { display: flex; flex-wrap: wrap; gap: 8px 20px; }
  .footer-col--nav li + li { margin-top: 0; }
  .site-footer__bottom {
    flex-direction: column; align-items: center; gap: 4px;
    padding: 20px 0 calc(20px + env(safe-area-inset-bottom));
    text-align: center; font-size: 12px;
  }
}