/* =========================================================
   致远钢结构 · 联系我们页面
   同源设计系统：浅蓝 #2C4A7C + 金 #E8943A
   ========================================================= */
:root {
  --blue: #2C4A7C;
  --blue-deep: #1E3A66;
  --blue-footer: #142A4A;
  --blue-overlay: #23426F;
  --border: #5C7BA8;
  --gold: #E8943A;
  --cream: #F4EFE4;
  --ink: #18242F;
  --muted: #5C6B7E;
  --white: #ffffff;
  --radius-card: 12px;
  --radius-btn: 8px;
  --shadow-soft: 0 10px 30px rgba(20, 42, 74, 0.10);
  --pad-x: 80px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: system-ui, -apple-system, 'Segoe UI', 'Microsoft YaHei', system-ui, sans-serif; color: var(--ink); background: var(--white); line-height: 1.7; -webkit-font-smoothing: antialiased; }
a { text-decoration: none; color: inherit; }
.container { max-width: 1440px; margin: 0 auto; padding: 0 var(--pad-x); }

/* ===================== 顶部导航 ===================== */
.site-header { position: sticky; top: 0; z-index: 50; background: rgba(44,74,124,0.96); backdrop-filter: saturate(140%) blur(6px); border-bottom: 1px solid rgba(255,255,255,0.12); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: flex; align-items: center; gap: 12px; color: var(--white); font-weight: 700; }
.brand-mark { width: 34px; height: 34px; border-radius: 8px; background: var(--gold); color: var(--blue-footer); display: grid; place-items: center; font-family: system-ui, -apple-system, 'Segoe UI', 'Microsoft YaHei', sans-serif; font-size: 22px; font-weight: 700; }
.brand-text { font-size: 19px; letter-spacing: .5px; }
.nav-links { display: flex; align-items: center; gap: 28px; }
.nav-links a { color: rgba(255,255,255,0.88); font-size: 15px; transition: color .2s; }
.nav-links a:hover { color: var(--gold); }
.nav-links a.active { color: var(--gold); font-weight: 500; }
.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 6px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--white); border-radius: 2px; }

/* ===================== 标题区 ===================== */
.contact-hero { background: linear-gradient(180deg, rgba(20,42,74,0.04), rgba(44,74,124,0.06)), radial-gradient(120% 100% at 80% 0%, rgba(232,148,58,0.12), transparent 55%); padding: 48px 0 40px; border-bottom: 1px solid rgba(92,123,168,0.18); }
.breadcrumb { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--muted); margin-bottom: 20px; }
.breadcrumb a:hover { color: var(--gold); }
.breadcrumb .current { color: var(--blue); font-weight: 500; }
.kicker { font-family: system-ui, -apple-system, 'Segoe UI', 'Microsoft YaHei', sans-serif; letter-spacing: 3px; color: var(--gold); font-size: 17px; }
.kicker.light { color: var(--gold); }
.contact-title { font-weight: 900; font-size: 44px; color: var(--blue-footer); margin: 6px 0 14px; letter-spacing: .5px; }
.contact-sub { color: var(--muted); font-size: 16px; max-width: 680px; }

/* ===================== 联系信息条 ===================== */
.contact-strip { padding: 36px 0; }
.strip-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.strip-item { display: flex; align-items: center; gap: 16px; padding: 22px; border: 1px solid rgba(92,123,168,0.25); border-radius: var(--radius-card); background: var(--white); transition: box-shadow .2s, border-color .2s; }
.strip-item:hover { box-shadow: var(--shadow-soft); border-color: var(--border); }
.strip-ico { flex: none; width: 46px; height: 46px; border-radius: 10px; background: rgba(232,148,58,0.14); color: var(--gold); display: grid; place-items: center; font-size: 22px; }
.strip-label { font-size: 13px; color: var(--muted); margin-bottom: 2px; }
.strip-value { font-size: 16px; font-weight: 500; color: var(--blue-footer); }
a.strip-value:hover { color: var(--gold); }

/* ===================== 主体：表单 + 信息 ===================== */
.contact-body { padding: 24px 0 80px; }
.contact-grid { display: grid; grid-template-columns: minmax(0,1.3fr) minmax(0,1fr); gap: 40px; align-items: start; }

/* 表单 */
.form-card { border: 1px solid rgba(92,123,168,0.25); border-radius: var(--radius-card); padding: 36px; background: var(--white); box-shadow: var(--shadow-soft); }
.form-title { font-size: 24px; color: var(--blue-footer); margin-bottom: 6px; }
.form-sub { font-size: 14px; color: var(--muted); margin-bottom: 24px; }
.req { color: #d9534f; }
.contact-form { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.field { display: flex; flex-direction: column; }
.field.full { grid-column: 1 / -1; }
.field label { font-size: 14px; color: var(--blue-deep); margin-bottom: 7px; font-weight: 500; }
.field input, .field select, .field textarea {
  font-family: inherit; font-size: 15px; color: var(--ink);
  border: 1px solid var(--border); border-radius: var(--radius-btn);
  padding: 12px 14px; background: var(--white); outline: none; transition: border-color .2s, box-shadow .2s; resize: vertical;
}
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--gold); box-shadow: 0 0 0 4px rgba(232,148,58,0.16); }
.field input.invalid, .field select.invalid { border-color: #d9534f; }
.err { color: #d9534f; font-size: 12px; margin-top: 5px; min-height: 14px; }
.submit-btn { grid-column: 1 / -1; justify-self: start; border: 0; cursor: pointer; background: var(--gold); color: var(--blue-footer); padding: 14px 36px; border-radius: var(--radius-btn); font-weight: 500; font-size: 16px; font-family: inherit; transition: background .2s, transform .2s; }
.submit-btn:hover { background: #F4C888; transform: translateY(-2px); }
.form-note { grid-column: 1 / -1; font-size: 12px; color: var(--muted); margin-top: 4px; }

/* 提交成功 */
.form-success { text-align: center; padding: 30px 10px; }
.success-ico { display: inline-grid; place-items: center; width: 56px; height: 56px; border-radius: 50%; background: rgba(232,148,58,0.18); color: var(--blue-footer); font-size: 28px; margin-bottom: 14px; }
.form-success h3 { color: var(--blue-footer); font-size: 22px; margin-bottom: 8px; }
.form-success p { color: var(--muted); margin-bottom: 18px; }
.btn-ghost { border: 1px solid var(--border); color: var(--blue-deep); padding: 12px 26px; border-radius: var(--radius-btn); cursor: pointer; font-family: inherit; background: none; transition: background .2s; }
.btn-ghost:hover { background: rgba(44,74,124,0.06); }

/* 右侧信息卡 */
.contact-aside { display: flex; flex-direction: column; gap: 24px; }
.info-card { border: 1px solid rgba(92,123,168,0.25); border-radius: var(--radius-card); padding: 28px; background: var(--cream); }
.info-card h3 { color: var(--blue-footer); font-size: 19px; margin-bottom: 16px; }
.info-line { display: flex; justify-content: space-between; gap: 12px; font-size: 14px; color: var(--muted); padding: 10px 0; border-bottom: 1px dashed rgba(92,123,168,0.3); }
.info-line:last-of-type { border-bottom: 0; }
.info-line span { color: var(--blue-deep); font-weight: 500; }
.qr { margin-top: 18px; text-align: center; }
.qr-box { width: 140px; height: 140px; margin: 0 auto 10px; border-radius: var(--radius-card); position: relative; }
.qr-box::after { content: "QR"; position: absolute; inset: 0; display: grid; place-items: center; color: rgba(255,255,255,0.85); font-family: system-ui, -apple-system, 'Segoe UI', 'Microsoft YaHei', sans-serif; font-size: 22px; letter-spacing: 2px; }
.qr p { font-size: 13px; color: var(--muted); }
.map-card { border: 1px solid rgba(92,123,168,0.25);border-radius: var(--radius-card); overflow: hidden; }
.map-placeholder { height: 220px; position: relative; }
.map-placeholder::after { content: ""; position: absolute; inset: 0; background: radial-gradient(120% 120% at 70% 30%, rgba(232,148,58,0.22), transparent 55%); }
.map-cap { font-size: 13px; color: var(--muted); padding: 14px 16px; }

/* ===================== CTA：与 FAQ 分类页共用视觉参数 ===================== */
.contact-body + .cta { background: var(--blue-overlay); color: var(--white); padding: 60px 0; }
.contact-body + .cta .cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 40px; flex-wrap: wrap; }
.contact-body + .cta .cta-text h2 { font-size: 30px; font-weight: 700; margin: 6px 0 10px; }
.contact-body + .cta .cta-text p { color: rgba(255,255,255,0.82); max-width: 540px; }
.contact-body + .cta .cta-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.contact-body + .cta .btn-primary {
  background: var(--gold); color: var(--blue-footer); padding: 14px 28px;
  border-radius: var(--radius-btn); font-weight: 500; transition: background .2s, transform .2s;
}
.contact-body + .cta .btn-primary:hover { background: #F4C888; transform: translateY(-2px); }
.contact-body + .cta .btn-ghost {
  border: 1px solid rgba(255,255,255,0.5); color: var(--white); padding: 14px 28px;
  border-radius: var(--radius-btn); transition: background .2s; background: none;
}
.contact-body + .cta .btn-ghost:hover { background: rgba(255,255,255,0.12); }

.footer-inner { display: flex; justify-content: space-between; gap: 50px; flex-wrap: wrap; }
.footer-brand { max-width: 360px; }
.footer-brand p { margin-top: 16px; font-size: 14px; color: rgba(255,255,255,0.7); line-height: 1.8; }
.footer-cols { display: flex; gap: 70px; flex-wrap: wrap; }
.footer-col h4 { color: var(--white); font-size: 15px; margin-bottom: 16px; }
.footer-col a { display: block; font-size: 14px; color: rgba(255,255,255,0.72); margin-bottom: 10px; transition: color .2s; }
.footer-col a:hover { color: var(--gold); }

/* ===================== 返回顶部 ===================== */
.back-top { position: fixed; right: 26px; bottom: 26px; z-index: 40; width: 46px; height: 46px; border-radius: 50%; border: 0; cursor: pointer; background: var(--blue); color: var(--white); font-size: 20px; box-shadow: var(--shadow-soft); opacity: 0; pointer-events: none; transition: opacity .3s, background .2s; }
.back-top.show { opacity: 1; pointer-events: auto; }
.back-top:hover { background: var(--blue-deep); }

/* ===================== 响应式 ===================== */
@media (max-width: 1024px) {
  :root { --pad-x: 40px; }
  .strip-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
  .contact-title { font-size: 36px; }
}
@media (max-width: 768px) {
  :root { --pad-x: 20px; }
  .nav-links { position: absolute; top: 72px; left: 0; right: 0; flex-direction: column; align-items: flex-start; gap: 0; background: var(--blue-deep); padding: 8px 20px 18px; max-height: 0; overflow: hidden; transition: max-height .3s; }
  .nav-links.open { max-height: 420px; }
  .nav-links a { padding: 12px 0; width: 100%; }
  .nav-toggle { display: flex; }
  .strip-grid { grid-template-columns: 1fr; }
  .contact-form { grid-template-columns: 1fr; }
  .form-card { padding: 24px; }
  .contact-title { font-size: 30px; }
  .contact-body + .cta .cta-inner { flex-direction: column; align-items: flex-start; }
}