/* ============================================================
 * style.css — 科技感深色主题，移动端优先响应式
 * ============================================================ */
:root {
  --bg: #0a0e1a;
  --bg-alt: #0f1525;
  --surface: #141b2e;
  --surface-2: #1b2440;
  --text: #e8edf7;
  --muted: #9aa6c2;
  --accent: #2de2e6;     /* cyan */
  --accent-2: #6c5ce7;   /* violet */
  --accent-grad: linear-gradient(135deg, #2de2e6 0%, #6c5ce7 100%);
  --border: rgba(255,255,255,0.08);
  --radius: 14px;
  --container: 1180px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 22px; }

/* ---------- Header ---------- */
.header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10,14,26,0.72);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { font-weight: 800; font-size: 20px; letter-spacing: 1px;
  background: var(--accent-grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.nav-links { display: flex; align-items: center; gap: 26px; }
.nav-links a { color: var(--muted); font-size: 15px; transition: color .2s; }
.nav-links a:hover { color: var(--text); }
.nav-cta {
  padding: 8px 16px; border-radius: 999px;
  background: var(--accent-grad); color: #04121a !important; font-weight: 600;
}
.nav-right { display: flex; align-items: center; gap: 14px; }
.lang-switch {
  background: transparent; color: var(--text); border: 1px solid var(--border);
  padding: 6px 12px; border-radius: 999px; cursor: pointer; font-size: 13px;
}
.lang-switch:hover { border-color: var(--accent); }
.hamburger { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 6px; }
.hamburger span { width: 24px; height: 2px; background: var(--text); display: block; transition: .3s; }

/* ---------- Hero ---------- */
.hero { position: relative; min-height: 100vh; display: flex; align-items: center; overflow: hidden; }
.hero-bg { position: absolute; inset: 0; background-color: #0f1525;
  background-image: linear-gradient(135deg, #111a30 0%, #1b2440 60%, #0f1525 100%);
  background-size: cover; background-position: center; filter: saturate(1.1); }
.hero-overlay { position: absolute; inset: 0;
  background: radial-gradient(circle at 30% 40%, rgba(108,92,231,0.35), transparent 60%),
              linear-gradient(180deg, rgba(10,14,26,0.6), rgba(10,14,26,0.92)); }
.hero-inner { position: relative; z-index: 2; max-width: 760px; padding-top: 80px; }
.badge { display: inline-block; padding: 6px 14px; border: 1px solid var(--accent);
  border-radius: 999px; color: var(--accent); font-size: 13px; margin-bottom: 18px; }
.hero h1 { font-size: clamp(34px, 5.5vw, 60px); line-height: 1.1; font-weight: 800; margin-bottom: 18px; }
.hero p { color: var(--muted); font-size: clamp(15px, 2vw, 19px); margin-bottom: 30px; max-width: 620px; }
.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; }
.btn { display: inline-block; padding: 13px 26px; border-radius: 999px; font-weight: 600; font-size: 15px; cursor: pointer; border: 0; transition: transform .15s, box-shadow .2s; }
.btn-primary { background: var(--accent-grad); color: #04121a; }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 30px rgba(45,226,230,0.35); }
.btn-ghost { background: transparent; border: 1px solid var(--border); color: var(--text); }
.btn-ghost:hover { border-color: var(--accent); }

/* ---------- Sections ---------- */
.section { padding: 90px 0; }
.section-alt { background: var(--bg-alt); }
.section-title { font-size: clamp(26px, 3.5vw, 40px); font-weight: 800; text-align: center; margin-bottom: 12px; }
.section-sub { text-align: center; color: var(--muted); margin-bottom: 44px; max-width: 640px; margin-left: auto; margin-right: auto; }

/* ---------- About ---------- */
.about-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 40px; align-items: center; }
.about-text p { color: var(--muted); margin-bottom: 16px; }
.stats { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.stat { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; text-align: center; }
.stat-num { display: block; font-size: 30px; font-weight: 800; background: var(--accent-grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.stat-label { color: var(--muted); font-size: 14px; }

/* ---------- Cards ---------- */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.cards-2 { grid-template-columns: repeat(2, 1fr); }
.cards-4 { grid-template-columns: repeat(4, 1fr); }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; transition: transform .2s, border-color .2s; }
.card:hover { transform: translateY(-4px); border-color: var(--accent); }
.card-img { height: 180px; background-size: cover; background-position: center; background-color: var(--surface-2); }
.card h3 { font-size: 18px; margin: 16px 18px 6px; }
.card p { color: var(--muted); font-size: 14px; margin: 0 18px 18px; }
.sol, .feat { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 26px; }
.sol h3, .feat h3 { font-size: 19px; margin-bottom: 10px; }
.sol p, .feat p { color: var(--muted); font-size: 14px; }

/* ---------- Contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 44px; }
.inquiry-form { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 10px; }
.field { position: relative; }
.field-full { grid-column: 1 / -1; }
.field input, .field textarea {
  width: 100%; padding: 16px 14px 8px; background: var(--surface); border: 1px solid var(--border);
  border-radius: 10px; color: var(--text); font-size: 15px; font-family: inherit; resize: vertical;
}
.field input:focus, .field textarea:focus { outline: none; border-color: var(--accent); }
.field label { position: absolute; left: 14px; top: 14px; color: var(--muted); font-size: 14px; pointer-events: none; transition: .15s; }
.field input:focus + label, .field input:not(:placeholder-shown) + label,
.field textarea:focus + label, .field textarea:not(:placeholder-shown) + label {
  top: 4px; font-size: 11px; color: var(--accent);
}
.inquiry-form .btn { grid-column: 1 / -1; justify-self: start; }
.form-msg { grid-column: 1/-1; font-size: 14px; }
.form-msg.ok { color: var(--accent); }
.form-msg.err { color: #ff6b6b; }
.contact-info { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px; align-self: start; }
.contact-info h3 { margin-bottom: 16px; }
.contact-info p { color: var(--muted); margin-bottom: 14px; font-size: 14px; }
.contact-info strong { color: var(--text); display: block; margin-bottom: 2px; }
.contact-info a { color: var(--accent); }

/* ---------- Footer ---------- */
.footer { background: var(--bg-alt); border-top: 1px solid var(--border); padding: 50px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 30px; }
.footer-tag { color: var(--muted); font-size: 14px; margin-top: 10px; max-width: 320px; }
.footer h4 { margin-bottom: 14px; font-size: 15px; }
.footer a { color: var(--muted); font-size: 14px; line-height: 2; }
.footer a:hover { color: var(--accent); }
.footer-bottom { margin-top: 30px; padding-top: 18px; border-top: 1px solid var(--border); color: var(--muted); font-size: 13px; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .about-grid, .contact-grid { grid-template-columns: 1fr; }
  .cards, .cards-4 { grid-template-columns: repeat(2, 1fr); }
  .cards-2 { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .nav-links {
    position: fixed; top: 64px; right: 0; height: calc(100vh - 64px); width: 70%;
    flex-direction: column; align-items: flex-start; gap: 18px; padding: 30px 26px;
    background: var(--surface); border-left: 1px solid var(--border); transform: translateX(100%); transition: transform .3s;
  }
  .nav-links.open { transform: translateX(0); }
  .hamburger { display: flex; }
  .inquiry-form { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .cards { grid-template-columns: 1fr; }
}