/* =======================================================
   global.css — 雷迅科技官网公共样式
   包含：Design Tokens / Reset / 导航 / 页脚 / 通用工具
   ======================================================= */

/* ===========================
   Design Tokens
   =========================== */
:root {
  --brand-primary:   #045297;
  --brand-dark:      #022d54;
  --brand-mid:       #1a6dba;
  --brand-light:     #e8f2fc;
  --brand-accent:    #0a9ece;

  --neutral-900: #0d1117;
  --neutral-800: #161b22;
  --neutral-700: #21262d;
  --neutral-500: #6e7681;
  --neutral-300: #d0d7de;
  --neutral-100: #f6f8fa;
  --neutral-50:  #ffffff;

  --font-sans:  'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-serif: 'LXGW WenKai', 'Noto Sans SC', sans-serif;

  --radius-sm:  4px;
  --radius-md:  8px;
  --radius-lg:  16px;
  --radius-full: 9999px;

  --shadow-sm:  0 1px 3px rgba(4,82,151,.08), 0 1px 2px rgba(4,82,151,.06);
  --shadow-md:  0 4px 16px rgba(4,82,151,.12), 0 2px 6px rgba(4,82,151,.08);
  --shadow-lg:  0 12px 40px rgba(4,82,151,.16);

  --transition: 0.24s cubic-bezier(0.16, 1, 0.3, 1);
  --nav-h: 68px;
  --container: 1200px;
}

/* ===========================
   CSS Reset
   =========================== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  color: var(--neutral-900);
  background: var(--neutral-50);
  line-height: 1.7;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }

/* ===========================
   Layout Utility
   =========================== */
.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===========================
   Navigation
   =========================== */
#navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  height: var(--nav-h);
  background: rgba(2,45,84,.98);
  transition: background var(--transition), box-shadow var(--transition);
}
#navbar.scrolled {
  background: rgba(255,255,255,.96);
  box-shadow: 0 1px 0 rgba(0,0,0,.08), 0 4px 16px rgba(0,0,0,.06);
  backdrop-filter: blur(16px);
}
.nav-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 40px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.nav-logo img {
  height: 32px;
  width: auto;
}
.nav-logo-text {
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  color: var(--brand-primary);
  display: none;
}
#navbar:not(.scrolled) .nav-logo-text { color: #fff; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1;
}
.nav-links a {
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: rgba(255,255,255,.85);
  transition: all var(--transition);
}
.nav-links a:hover,
.nav-links a.active {
  color: #fff;
  background: rgba(255,255,255,.15);
}
#navbar.scrolled .nav-links a {
  color: var(--neutral-700);
}
#navbar.scrolled .nav-links a:hover,
#navbar.scrolled .nav-links a.active {
  color: var(--brand-primary);
  background: var(--brand-light);
}

.nav-cta { margin-left: auto; }
.btn-ghost {
  border: 1.5px solid rgba(255,255,255,.6);
  color: #fff;
  padding: 9px 20px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 500;
  transition: all var(--transition);
  display: inline-block;
}
.btn-ghost:hover {
  background: rgba(255,255,255,.15);
}
#navbar.scrolled .btn-ghost {
  border-color: var(--brand-primary);
  color: var(--brand-primary);
}
#navbar.scrolled .btn-ghost:hover {
  background: var(--brand-light);
}

.nav-mobile-btn {
  display: none;
  margin-left: auto;
  padding: 8px;
  border-radius: var(--radius-sm);
  color: #fff;
  align-items: center;
  justify-content: center;
}
#navbar.scrolled .nav-mobile-btn { color: var(--neutral-700); }
.nav-mobile-btn svg { width: 22px; height: 22px; }

#mobile-menu {
  display: none;
  position: fixed;
  top: var(--nav-h);
  left: 0; right: 0;
  background: rgba(255,255,255,.98);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--neutral-300);
  z-index: 999;
  padding: 16px 24px 24px;
}
#mobile-menu.open { display: block; }
.mobile-link {
  display: block;
  padding: 12px 0;
  font-size: 16px;
  color: var(--neutral-700);
  border-bottom: 1px solid var(--neutral-100);
}
.mobile-link.active { color: var(--brand-primary); font-weight: 500; }
.mobile-cta { margin-top: 16px; }
.mobile-cta .btn-primary {
  width: 100%;
  justify-content: center;
  text-align: center;
}

/* ===========================
   Footer
   =========================== */
footer {
  background: var(--neutral-900);
  color: rgba(255,255,255,.65);
  padding: 64px 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255,255,255,.1);
}
.footer-brand .footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}
.footer-brand .footer-logo img { height: 30px; width: auto; }
.footer-brand .footer-logo-text {
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  color: #fff;
}
.footer-brand p { font-size: 13px; line-height: 1.7; max-width: 280px; }
.footer-col h4 {
  font-size: 14px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 18px;
}
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a,
.footer-col ul li {
  font-size: 13px;
  color: rgba(255,255,255,.55);
  transition: color var(--transition);
}
.footer-col ul li a:hover { color: #fff; }
.footer-bottom {
  padding: 20px 0;
  text-align: center;
  font-size: 12px;
  color: rgba(255,255,255,.35);
}

/* ===========================
   Common Buttons
   =========================== */
.btn-primary {
  background: var(--brand-primary);
  color: #fff;
  padding: 10px 24px;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 500;
  white-space: nowrap;
  transition: all var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 4px 16px rgba(4,82,151,.35);
}
.btn-primary svg { width: 18px; height: 18px; flex-shrink: 0; }
.btn-primary:hover {
  background: var(--brand-mid);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(4,82,151,.45);
}

/* ===========================
   Scroll Reveal
   =========================== */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===========================
   Responsive — Nav & Footer
   =========================== */
@media (max-width: 989px) {
  .nav-links, .nav-cta { display: none; }
  .nav-mobile-btn { display: flex; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
}
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}