/* ============================================================
   The Agency — Landing Style V1
   Aesthetic: High-Tech SaaS — Cool Blue & White
   Palette: Primary #0052CC · Surface White · Steel Grays
   Fonts: PingFang SC / Noto Sans SC (与项目一致)
   ============================================================ */

:root {
  --font-sans-system: system-ui, -apple-system, "PingFang SC", "Noto Sans SC", "Segoe UI", Roboto, sans-serif;
  --font-mono-system: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

  /* V1: White base, blue accent */
  --bg:       #ffffff;
  --bg2:      #f5f7fa;
  --bg3:      #eef2f8;
  --surface:  #f0f4fb;
  --surface2: #e8edf6;
  --border:   rgba(0,82,204,0.10);
  --border2:  rgba(0,82,204,0.25);
  --gold:     #0052CC;
  --gold2:    #003d99;
  --gold-dim: rgba(0,82,204,0.09);
  --white:    #0f172a;
  --muted:    #64748b;
  --muted2:   #475569;
  --text:     #334155;
  --green:    #16a34a;
  --cyan:     #0ea5e9;

  --r:   6px;
  --r2:  12px;
  --r3:  20px;
  --max: 1200px;
  --font-serif: var(--font-sans-system);
  --font-sans:  var(--font-sans-system);
  --font-mono:  var(--font-mono-system);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img, svg { display: block; }
button { cursor: pointer; border: none; background: none; font: inherit; }
ul { list-style: none; }

/* Grid texture */
body::before {
  content: '';
  position: fixed; inset: 0;
  background-image:
    linear-gradient(rgba(0,82,204,0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,82,204,0.025) 1px, transparent 1px);
  background-size: 52px 52px;
  pointer-events: none;
  z-index: 0;
}

/* ── NAV ──────────────────────────────────────────────────── */
.nav {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 48px; height: 68px;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}
.nav-logo {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--font-serif);
  font-size: 17px; font-weight: 600; color: var(--white);
}
.nav-links {
  display: flex; align-items: center; gap: 34px;
}
.nav-links a {
  font-size: 13.5px; font-weight: 500;
  color: var(--muted2); letter-spacing: 0.02em;
  transition: color 0.2s;
}
.nav-links a:hover, .nav-links a.active { color: var(--white); }
.nav-right { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }

/* ── BUTTONS ─────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 22px; border-radius: var(--r);
  font-family: var(--font-sans); font-size: 14px;
  font-weight: 600; letter-spacing: 0.02em;
  transition: all 0.2s; white-space: nowrap; cursor: pointer;
}
.btn-primary { background: var(--gold); color: #ffffff; }
.btn-primary:hover {
  background: var(--gold2); transform: translateY(-1px);
  box-shadow: 0 8px 24px rgba(0,82,204,0.28);
}
.btn-ghost {
  background: transparent; color: var(--text);
  border: 1px solid var(--border);
}
.btn-ghost:hover { border-color: var(--muted); color: var(--white); }
.btn-outline-gold {
  background: transparent; color: var(--gold);
  border: 1px solid var(--border2);
}
.btn-outline-gold:hover { background: var(--gold-dim); }
.btn-lg  { padding: 13px 30px; font-size: 15px; }
.btn-xl  { padding: 16px 40px; font-size: 16px; }

/* ── TYPE ─────────────────────────────────────────────────── */
.gold  { color: var(--gold); }
.muted { color: var(--muted2); }
.white { color: var(--white); }
.italic { font-style: italic; }

.eyebrow {
  font-size: 11.5px; font-weight: 600;
  letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--gold); display: inline-block;
}
.eyebrow-row {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: 11.5px; font-weight: 600;
  letter-spacing: 0.14em; text-transform: uppercase; color: var(--gold);
  margin-bottom: 20px;
}
.eyebrow-row::before {
  content: ''; display: block; width: 24px; height: 1px; background: var(--gold);
}

.display {
  font-family: var(--font-serif); font-weight: 700;
  color: var(--white); line-height: 1.1; letter-spacing: -0.02em;
}
.display-xl { font-size: clamp(46px, 5.5vw, 82px); }
.display-lg { font-size: clamp(34px, 4vw, 58px); }
.display-md { font-size: clamp(26px, 3vw, 42px); }
.display-sm { font-size: clamp(20px, 2.5vw, 32px); }

/* ── LAYOUT ──────────────────────────────────────────────── */
.container { max-width: var(--max); margin: 0 auto; padding: 0 48px; }
.section    { padding: 100px 0; position: relative; }
.section-sm { padding: 64px 0; position: relative; }
.section-xs { padding: 40px 0; position: relative; }
.text-center { text-align: center; }

.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.grid-3 { display: grid; grid-template-columns: repeat(3,1fr); gap: 32px; }
.grid-4 { display: grid; grid-template-columns: repeat(4,1fr); gap: 24px; }

/* ── CARDS ───────────────────────────────────────────────── */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--r2);
  padding: 32px;
  transition: border-color 0.2s, transform 0.2s;
  position: relative; overflow: hidden;
}
.card:hover { border-color: rgba(0,82,204,0.2); transform: translateY(-2px); }
.card-gold {
  border-color: var(--border2);
  background: linear-gradient(135deg, rgba(0,82,204,0.05) 0%, var(--surface) 60%);
}

/* ── DIVIDER ─────────────────────────────────────────────── */
.divider { height: 1px; background: var(--border); }

/* ── TAGS ────────────────────────────────────────────────── */
.tag {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 4px 10px; border-radius: 4px;
  font-size: 11.5px; font-family: var(--font-mono);
  border: 1px solid var(--border); color: var(--muted2);
}
.tag-gold { border-color: var(--border2); color: var(--gold); background: var(--gold-dim); }

/* ── FOOTER ──────────────────────────────────────────────── */
.footer { padding: 72px 0 40px; border-top: 1px solid var(--border); }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 48px; }
.footer-brand p { font-size: 14px; color: var(--muted); line-height: 1.7; margin-top: 14px; max-width: 260px; }
.footer-col h4 {
  font-size: 11.5px; font-weight: 600; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--muted); margin-bottom: 16px;
}
.footer-col a {
  display: block; font-size: 14px; color: var(--muted2);
  margin-bottom: 10px; transition: color 0.2s;
}
.footer-col a:hover { color: var(--white); }
.footer-bottom {
  display: flex; justify-content: space-between; align-items: center;
  margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--border);
  font-size: 13px; color: var(--muted);
}

/* ── ANIMATIONS ──────────────────────────────────────────── */
@keyframes fadeUp { from { opacity:0; transform:translateY(20px); } to { opacity:1; transform:none; } }
@keyframes fadeIn { from { opacity:0; } to { opacity:1; } }
@keyframes float  { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-8px)} }
@keyframes pulse  { 0%,100%{opacity:1} 50%{opacity:0.4} }
@keyframes spin   { to { transform: rotate(360deg); } }
@keyframes shimmer {
  0%  { background-position: -200% center; }
  100%{ background-position:  200% center; }
}
@keyframes blob {
  0%,100%{ border-radius: 60% 40% 30% 70% / 60% 30% 70% 40%; }
  50%     { border-radius: 30% 60% 70% 40% / 50% 60% 30% 60%; }
}

.anim-fade-up   { animation: fadeUp 0.65s ease both; }
.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }
.delay-5 { animation-delay: 0.5s; }

/* ── MOBILE ──────────────────────────────────────────────── */
.mobile-btn { display: none; padding: 8px; }
.mobile-btn span {
  display: block; width: 22px; height: 1.5px; background: var(--muted2); margin: 5px 0;
  transition: transform 0.2s ease, opacity 0.2s ease;
  transform-origin: center;
}
.mobile-btn.open span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.mobile-btn.open span:nth-child(2) { opacity: 0; }
.mobile-btn.open span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

@media (max-width: 900px) {
  .nav { padding: 0 24px; position: relative; justify-content: flex-start; }
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 24px 20px;
    margin: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    box-shadow: 0 16px 48px rgba(15, 23, 42, 0.08);
    z-index: 101;
  }
  .nav-links a {
    padding: 14px 0;
    border-bottom: 1px solid var(--border);
    font-size: 15px;
  }
  .nav-links a:last-child { border-bottom: none; }
  .nav.nav-open .nav-links {
    display: flex;
  }
  .nav-logo { flex-shrink: 0; min-width: 0; }
  .nav-right {
    margin-left: auto;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 6px;
    flex-wrap: wrap;
    max-width: min(100%, calc(100vw - 120px));
    min-width: 0;
  }
  .nav-right .btn {
    padding: 6px 10px;
    font-size: 11px;
    white-space: nowrap;
  }
  .mobile-btn { display: block; flex-shrink: 0; }
  .container { padding: 0 20px; }
  .section { padding: 64px 0; }
  .grid-2 { grid-template-columns: 1fr; gap: 28px; }
  .grid-3 { grid-template-columns: 1fr 1fr; gap: 20px; }
  .grid-4 { grid-template-columns: 1fr 1fr; gap: 16px; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
}
@media (max-width: 600px) {
  .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .display-xl { font-size: 36px; }
}