/* ============================================
   GooGeek 谷极客 — Site-wide Public CSS
   Shared design system for all pages
   ============================================ */

:root {
  --navy-900: #071426;
  --navy-800: #0B1930;
  --navy-700: #10213D;

  --brand-blue: #2563EB;
  --brand-blue-light: #3978FF;
  --tech-cyan: #21C4D6;
  --ai-purple: #6658E8;

  --bg-white: #FFFFFF;
  --bg-light: #F8FAFC;
  --bg-soft: #F5F7FB;
  --bg-blue: #EEF3F9;

  --text-primary: #172033;
  --text-secondary: #526075;
  --text-tertiary: #667085;

  --border-light: rgba(15, 35, 65, 0.08);
  --border-dark: rgba(255, 255, 255, 0.10);

  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --shadow-sm: 0 2px 8px rgba(15, 35, 65, 0.05);
  --shadow-md: 0 12px 32px rgba(15, 35, 65, 0.08);
  --shadow-lg: 0 24px 64px rgba(15, 35, 65, 0.12);

  --container: 1320px;

  --section-gap-lg: 112px;
  --section-gap-md: 88px;
  --section-gap-sm: 64px;

  --header-h: 72px;
  --header-h-mobile: 64px;

  --font-en: 'Inter', 'Manrope', Arial, sans-serif;
  --font-cn: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Manrope', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;

  --gradient-brand: linear-gradient(90deg, #3978FF 0%, #21C4D6 100%);
  --gradient-navy: linear-gradient(135deg, #071426 0%, #0B1930 58%, #102A49 100%);
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; font-size: 16px; }
body { font-family: var(--font-body); color: var(--text-primary); background: var(--bg-white); line-height: 1.7; overflow-x: hidden; -webkit-font-smoothing: antialiased; }
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
ul { list-style: none; }
:focus-visible { outline: 2px solid var(--brand-blue); outline-offset: 3px; border-radius: 4px; }

/* ── Container ── */
.container { max-width: var(--container); margin: 0 auto; padding: 0 32px; width: 100%; }

/* ── Section spacing ── */
.section { padding: var(--section-gap-lg) 0; }
.section-md { padding: var(--section-gap-md) 0; }
.section-sm { padding: var(--section-gap-sm) 0; }

/* ── Eyebrow / Section headers ── */
.eyebrow { font-family: var(--font-en); font-size: 13px; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; color: var(--brand-blue); margin-bottom: 16px; display: inline-block; }
.eyebrow.on-dark { color: var(--tech-cyan); }
.section-title { font-size: clamp(26px, 3.8vw, 44px); font-weight: 800; line-height: 1.25; letter-spacing: -.02em; margin-bottom: 20px; color: var(--text-primary); }
.section-title.on-dark { color: var(--bg-white); }
.section-title .accent { background: var(--gradient-brand); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.section-desc { font-size: 18px; color: var(--text-secondary); max-width: 720px; line-height: 1.8; }
.section-desc.on-dark { color: rgba(255, 255, 255, .72); }
.section-head { margin-bottom: 48px; }
.section-head.center { text-align: center; }
.section-head.center .section-desc { margin: 0 auto; }

/* ── Skip link ── */
.skip-link { position: absolute; top: -100px; left: 0; z-index: 2000; padding: 12px 24px; background: var(--brand-blue); color: #fff; font-size: 14px; border-radius: 0 0 8px 0; transition: top .2s; }
.skip-link:focus { top: 0; }

/* ── Buttons ── */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; font-family: var(--font-en); font-weight: 600; font-size: 16px; padding: 14px 28px; border-radius: var(--radius-md); transition: all .3s ease; white-space: nowrap; cursor: pointer; border: 2px solid transparent; line-height: 1.4; min-height: 44px; }
.btn-primary { background: var(--brand-blue); color: #fff; }
.btn-primary:hover { background: #1D4ED8; transform: translateY(-2px); box-shadow: 0 8px 24px rgba(37, 99, 235, .35); }
.btn-outline { background: transparent; color: var(--brand-blue); border-color: var(--brand-blue); }
.btn-outline:hover { background: var(--brand-blue); color: #fff; }
.btn-outline-light { background: transparent; color: #fff; border-color: rgba(255, 255, 255, .4); }
.btn-outline-light:hover { background: rgba(255, 255, 255, .1); border-color: #fff; }
.btn-lg { padding: 16px 36px; font-size: 17px; }
.btn-sm { padding: 10px 20px; font-size: 14px; }

/* ── Tags ── */
.tag { display: inline-flex; align-items: center; gap: 6px; padding: 6px 14px; border-radius: 100px; font-size: 13px; font-weight: 500; background: var(--bg-blue); color: var(--brand-blue); border: 1px solid rgba(37, 99, 235, .12); }
.tag-dark { background: rgba(255, 255, 255, .08); color: rgba(255, 255, 255, .8); border: 1px solid rgba(255, 255, 255, .12); }

/* ── Header / Navigation ── */
.site-header { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; transition: all .3s ease; height: var(--header-h); display: flex; align-items: center; }
.site-header.scrolled { background: rgba(255, 255, 255, .95); backdrop-filter: blur(16px); box-shadow: 0 1px 8px rgba(15, 35, 65, .06); border-bottom: 1px solid var(--border-light); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; width: 100%; gap: 24px; }
.logo { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.logo-mark { width: 40px; height: 40px; border-radius: 10px; background: var(--gradient-brand); display: flex; align-items: center; justify-content: center; font-family: var(--font-en); font-weight: 900; font-size: 22px; color: #fff; flex-shrink: 0; }
.logo-text { display: flex; flex-direction: column; line-height: 1.1; }
.logo-text .en { font-family: var(--font-en); font-weight: 800; font-size: 18px; color: var(--text-primary); }
.logo-text .cn { font-family: var(--font-cn); font-size: 12px; color: var(--text-tertiary); }
.site-header:not(.scrolled) .logo-text .en { color: #fff; }
.site-header:not(.scrolled) .logo-text .cn { color: rgba(255, 255, 255, .6); }
.nav-menu { display: flex; align-items: center; gap: 4px; flex: 1; justify-content: center; }
.nav-item { position: relative; }
.nav-link { display: flex; align-items: center; gap: 4px; padding: 8px 14px; font-size: 15px; font-weight: 500; color: var(--text-secondary); border-radius: 8px; transition: all .2s; cursor: pointer; }
.nav-link:hover { color: var(--brand-blue); background: rgba(37, 99, 235, .06); }
.nav-link.active { color: var(--brand-blue); font-weight: 600; }
.nav-link .caret { width: 12px; height: 12px; transition: transform .2s; }
.nav-item.open .caret { transform: rotate(180deg); }
.site-header:not(.scrolled) .nav-link { color: rgba(255, 255, 255, .85); }
.site-header:not(.scrolled) .nav-link:hover { color: #fff; background: rgba(255, 255, 255, .1); }
.site-header:not(.scrolled) .nav-link.active { color: #fff; }
.dropdown { position: absolute; top: 100%; left: 50%; transform: translateX(-50%) translateY(8px); background: #fff; border-radius: var(--radius-lg); box-shadow: var(--shadow-lg); border: 1px solid var(--border-light); padding: 12px; min-width: 220px; opacity: 0; visibility: hidden; transition: all .25s ease; z-index: 10; }
.nav-item.open .dropdown { opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0); }
.dropdown a { display: flex; align-items: center; gap: 10px; padding: 10px 14px; border-radius: 8px; font-size: 14px; color: var(--text-secondary); transition: all .15s; }
.dropdown a:hover { background: var(--bg-blue); color: var(--brand-blue); }
.dropdown a .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--tech-cyan); flex-shrink: 0; }
.nav-cta { flex-shrink: 0; }
.nav-toggle { display: none; width: 44px; height: 44px; flex-direction: column; justify-content: center; align-items: center; gap: 5px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--text-primary); border-radius: 2px; transition: all .3s; }
.site-header:not(.scrolled) .nav-toggle span { background: #fff; }
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ── Mobile menu ── */
.mobile-menu { position: fixed; top: 0; right: -100%; width: min(380px, 85vw); height: 100vh; background: var(--navy-900); z-index: 1100; transition: right .35s ease; overflow-y: auto; padding: 80px 28px 32px; display: flex; flex-direction: column; gap: 6px; }
.mobile-menu.open { right: 0; }
.mobile-menu-overlay { position: fixed; inset: 0; background: rgba(7, 20, 38, .5); z-index: 1050; opacity: 0; visibility: hidden; transition: all .3s; }
.mobile-menu-overlay.open { opacity: 1; visibility: visible; }
.mm-link { display: flex; align-items: center; justify-content: space-between; padding: 14px 16px; border-radius: 10px; color: rgba(255, 255, 255, .85); font-size: 16px; font-weight: 500; transition: all .2s; }
.mm-link:hover, .mm-link.active { background: rgba(255, 255, 255, .08); color: #fff; }
.mm-sub { padding-left: 20px; display: none; }
.mm-sub.open { display: flex; flex-direction: column; gap: 2px; padding-left: 20px; }
.mm-sub a { padding: 10px 16px; font-size: 14px; color: rgba(255, 255, 255, .6); border-radius: 8px; }
.mm-cta { margin-top: auto; padding-top: 24px; }
.mm-close { position: absolute; top: 20px; right: 20px; width: 44px; height: 44px; border-radius: 50%; background: rgba(255, 255, 255, .08); display: flex; align-items: center; justify-content: center; color: #fff; font-size: 20px; }

/* ── Breadcrumb ── */
.breadcrumb { display: flex; align-items: center; gap: 8px; font-size: 14px; color: var(--text-tertiary); margin-bottom: 24px; flex-wrap: wrap; }
.breadcrumb a { color: var(--text-secondary); transition: color .2s; }
.breadcrumb a:hover { color: var(--brand-blue); }
.breadcrumb .sep { color: var(--text-tertiary); opacity: .5; }
.breadcrumb .current { color: var(--text-primary); font-weight: 500; }

/* ── FAQ ── */
.faq-list { max-width: 820px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item { border: 1px solid var(--border-light); border-radius: var(--radius-md); overflow: hidden; background: #fff; transition: all .25s; }
.faq-item.open { border-color: rgba(37, 99, 235, .2); box-shadow: var(--shadow-sm); }
.faq-q { width: 100%; display: flex; align-items: center; justify-content: space-between; padding: 20px 24px; font-size: 17px; font-weight: 600; color: var(--text-primary); text-align: left; cursor: pointer; gap: 16px; background: none; border: none; font-family: inherit; }
.faq-q .fq-icon { width: 24px; height: 24px; flex-shrink: 0; color: var(--brand-blue); transition: transform .3s; }
.faq-item.open .faq-q .fq-icon { transform: rotate(45deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .35s ease; }
.faq-item.open .faq-a { max-height: 500px; }
.faq-a-inner { padding: 0 24px 20px; font-size: 15px; color: var(--text-secondary); line-height: 1.8; }

/* ── Form controls ── */
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.form-group { margin-bottom: 14px; }
.form-group.full { grid-column: span 2; }
.form-group label { display: block; font-size: 13px; font-weight: 600; color: var(--text-secondary); margin-bottom: 6px; }
.form-group label .req { color: #DC2626; }
.form-control { width: 100%; padding: 12px 16px; border: 1.5px solid var(--border-light); border-radius: 10px; font-size: 15px; font-family: inherit; color: var(--text-primary); background: var(--bg-light); transition: all .2s; min-height: 48px; }
.form-control:focus { outline: none; border-color: var(--brand-blue); background: #fff; box-shadow: 0 0 0 3px rgba(37, 99, 235, .1); }
textarea.form-control { resize: vertical; min-height: 80px; }
select.form-control { cursor: pointer; appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%23667085' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10z'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 16px center; padding-right: 40px; }
.form-note { font-size: 13px; color: var(--text-tertiary); margin-top: 12px; text-align: center; }
.form-success { display: none; padding: 20px; border-radius: var(--radius-md); background: rgba(34, 197, 94, .08); border: 1px solid rgba(34, 197, 94, .2); color: #16A34A; font-size: 15px; font-weight: 600; text-align: center; margin-top: 16px; }
.form-success.show { display: block; }
.form-error { font-size: 12px; color: #DC2626; margin-top: 4px; display: none; }
.form-error.show { display: block; }

/* ── Back to top ── */
.back-top { position: fixed; bottom: 32px; right: 32px; width: 48px; height: 48px; border-radius: 50%; background: var(--brand-blue); color: #fff; display: flex; align-items: center; justify-content: center; box-shadow: var(--shadow-lg); opacity: 0; visibility: hidden; transform: translateY(20px); transition: all .3s; z-index: 900; border: none; cursor: pointer; }
.back-top.show { opacity: 1; visibility: visible; transform: translateY(0); }
.back-top:hover { background: #1D4ED8; transform: translateY(-4px); }

/* ── Toast ── */
.toast { position: fixed; bottom: 32px; left: 50%; transform: translateX(-50%) translateY(80px); background: var(--navy-800); color: #fff; padding: 14px 28px; border-radius: 100px; font-size: 15px; font-weight: 500; box-shadow: var(--shadow-lg); opacity: 0; transition: all .35s ease; z-index: 1200; display: flex; align-items: center; gap: 8px; }
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
.toast svg { width: 20px; height: 20px; color: var(--tech-cyan); }

/* ── Reveal animation ── */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }
.reveal-delay-1 { transition-delay: .1s; }
.reveal-delay-2 { transition-delay: .2s; }

/* ── Footer ── */
.site-footer { background: var(--navy-900); padding: 72px 0 32px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 48px; }
.footer-brand .logo-text .en { color: #fff; }
.footer-brand .logo-text .cn { color: rgba(255, 255, 255, .5); }
.footer-brand p { font-size: 14px; color: rgba(255, 255, 255, .5); line-height: 1.7; margin-top: 20px; max-width: 320px; }
.footer-col h4 { font-size: 15px; font-weight: 700; color: #fff; margin-bottom: 20px; }
.footer-col ul { display: flex; flex-direction: column; gap: 12px; }
.footer-col a { font-size: 14px; color: rgba(255, 255, 255, .5); transition: color .2s; }
.footer-col a:hover { color: var(--tech-cyan); }
.footer-bottom { display: flex; align-items: center; justify-content: space-between; padding-top: 28px; border-top: 1px solid rgba(255, 255, 255, .06); flex-wrap: wrap; gap: 16px; }
.footer-bottom p { font-size: 13px; color: rgba(255, 255, 255, .4); }
.footer-links { display: flex; gap: 24px; }
.footer-links a { font-size: 13px; color: rgba(255, 255, 255, .4); transition: color .2s; }
.footer-links a:hover { color: var(--tech-cyan); }

/* ── Responsive public rules ── */
@media (max-width: 1200px) {
  .footer-grid { grid-template-columns: 2fr 1fr 1fr 1fr 1fr; }
}
@media (max-width: 1024px) {
  .nav-menu { display: none; }
  .nav-toggle { display: flex; }
  .nav-cta { display: none; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .footer-brand { grid-column: span 2; }
  .form-row { grid-template-columns: 1fr; }
  .form-group.full { grid-column: span 1; }
}
@media (max-width: 768px) {
  :root { --header-h: 64px; }
  .container { padding: 0 20px; }
  .section { padding: 64px 0; }
  .section-md { padding: 56px 0; }
  .section-sm { padding: 48px 0; }
  .section-title { font-size: 26px; }
  .section-desc { font-size: 16px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: span 2; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .back-top { bottom: 20px; right: 20px; width: 44px; height: 44px; }
}
@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; }
  .footer-brand { grid-column: span 1; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}
@media print {
  .site-header, .nav-toggle, .mobile-menu, .mobile-menu-overlay, .back-top { display: none !important; }
  .section { padding: 32px 0; }
}