/* ============================================================
   TOPO DATA — 香港拓撲數據科技有限公司 企業網站
   ============================================================ */

:root {
  --bg: #0b1220;
  --bg-alt: #0e1730;
  --card: rgba(255, 255, 255, 0.04);
  --card-border: rgba(255, 255, 255, 0.09);
  --text: #e8eef8;
  --muted: #96a6c0;
  --accent: #2dd4bf;
  --accent-2: #38bdf8;
  --radius: 14px;
  --header-h: 68px;
  --font: "Inter", "Noto Sans TC", -apple-system, "Segoe UI", "PingFang TC",
    "Microsoft JhengHei", sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: var(--header-h); }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.container { width: min(1120px, 92%); margin: 0 auto; }

a { color: inherit; text-decoration: none; }

.grad {
  background: linear-gradient(92deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: var(--header-h);
  transition: background 0.25s ease, box-shadow 0.25s ease;
}
.site-header.scrolled {
  background: rgba(11, 18, 32, 0.88);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.07);
}
.nav-wrap {
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-mark { width: 30px; height: 30px; flex: none; }
.brand-text {
  font-weight: 800;
  letter-spacing: 0.08em;
  font-size: 1.05rem;
  line-height: 1.15;
  display: flex;
  flex-direction: column;
}
.brand-text small {
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.28em;
  color: var(--muted);
}
.main-nav { display: flex; align-items: center; gap: 28px; }
.main-nav a {
  font-size: 0.95rem;
  color: var(--muted);
  transition: color 0.2s;
}
.main-nav a:hover { color: var(--text); }
.lang-toggle {
  font: inherit;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent);
  background: transparent;
  border: 1px solid rgba(45, 212, 191, 0.45);
  border-radius: 999px;
  padding: 4px 14px;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}
.lang-toggle:hover { background: rgba(45, 212, 191, 0.12); }

.nav-burger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  cursor: pointer;
  padding: 6px;
}
.nav-burger span {
  width: 22px; height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.25s, opacity 0.25s;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: 92vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  background:
    radial-gradient(900px 500px at 80% -10%, rgba(56, 189, 248, 0.14), transparent 60%),
    radial-gradient(700px 500px at 10% 110%, rgba(45, 212, 191, 0.12), transparent 60%),
    var(--bg);
}
#netCanvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0.55;
}
.hero-inner { position: relative; z-index: 1; padding: calc(var(--header-h) + 48px) 0 72px; }
.hero-badge {
  display: inline-block;
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  color: var(--accent);
  border: 1px solid rgba(45, 212, 191, 0.35);
  border-radius: 999px;
  padding: 6px 16px;
  margin-bottom: 26px;
  background: rgba(45, 212, 191, 0.07);
}
.hero-title {
  font-size: clamp(2.2rem, 5.4vw, 3.9rem);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: 0.02em;
  margin-bottom: 22px;
}
.hero-sub {
  max-width: 620px;
  color: var(--muted);
  font-size: 1.06rem;
  margin-bottom: 36px;
}
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }

.btn {
  display: inline-block;
  font-weight: 600;
  font-size: 0.98rem;
  padding: 13px 30px;
  border-radius: 10px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s;
}
.btn-primary {
  background: linear-gradient(92deg, var(--accent), var(--accent-2));
  color: #06281f;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 28px rgba(45, 212, 191, 0.28); }
.btn-ghost { border-color: var(--card-border); color: var(--text); background: var(--card); }
.btn-ghost:hover { background: rgba(255, 255, 255, 0.09); }

/* ---------- Sections ---------- */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }
.tag {
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.22em;
  color: var(--accent);
  text-transform: uppercase;
  margin-bottom: 12px;
}
.section-title {
  font-size: clamp(1.6rem, 3.4vw, 2.3rem);
  font-weight: 800;
  letter-spacing: 0.02em;
  margin-bottom: 12px;
}
.section-sub { color: var(--muted); margin-bottom: 52px; max-width: 640px; }

/* ---------- Cards ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.card {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 30px 26px;
  transition: transform 0.22s ease, border-color 0.22s ease, background 0.22s;
}
.card:hover {
  transform: translateY(-5px);
  border-color: rgba(45, 212, 191, 0.4);
  background: rgba(45, 212, 191, 0.05);
}
.card-icon {
  width: 48px; height: 48px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  margin-bottom: 18px;
  color: var(--accent);
  background: rgba(45, 212, 191, 0.1);
}
.card-icon svg { width: 24px; height: 24px; }
.card h3 { font-size: 1.12rem; font-weight: 700; margin-bottom: 8px; }
.card p { color: var(--muted); font-size: 0.95rem; }

/* ---------- About ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 56px;
  align-items: start;
  margin-top: 28px;
}
.about-text p { color: var(--muted); margin-bottom: 18px; }
.about-text p:first-child { color: var(--text); }
.why-list { list-style: none; display: grid; gap: 14px; }
.why-list li {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 18px 22px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.why-list strong { font-size: 1rem; }
.why-list strong::before { content: "▸ "; color: var(--accent); }
.why-list span { color: var(--muted); font-size: 0.92rem; }

/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 48px;
  align-items: start;
}
.contact-info { display: grid; gap: 26px; }
.contact-item { display: grid; gap: 4px; }
.contact-label {
  font-size: 0.82rem;
  letter-spacing: 0.18em;
  color: var(--accent);
  font-weight: 700;
}
.contact-item a { color: var(--text); font-size: 1.05rem; }
.contact-item a:hover { color: var(--accent-2); }

.contact-form {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius);
  padding: 30px;
  display: grid;
  gap: 18px;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.contact-form label { display: grid; gap: 6px; font-size: 0.92rem; color: var(--muted); }
.contact-form input,
.contact-form textarea {
  font: inherit;
  color: var(--text);
  background: rgba(11, 18, 32, 0.6);
  border: 1px solid var(--card-border);
  border-radius: 9px;
  padding: 11px 14px;
  resize: vertical;
  transition: border-color 0.2s;
}
.contact-form input:focus,
.contact-form textarea:focus {
  outline: none;
  border-color: var(--accent);
}
.contact-form .btn { justify-self: start; }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--card-border);
  padding: 40px 0;
  background: var(--bg-alt);
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}
.footer-tagline { color: var(--muted); font-size: 0.9rem; margin-top: 6px; }
.footer-rights { color: var(--muted); font-size: 0.85rem; }

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .card-grid { grid-template-columns: repeat(2, 1fr); }
  .about-grid, .contact-grid { grid-template-columns: 1fr; gap: 36px; }
}

@media (max-width: 640px) {
  .card-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .section { padding: 72px 0; }

  .nav-burger { display: flex; }
  .main-nav {
    position: fixed;
    top: var(--header-h);
    right: 0;
    left: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
    background: rgba(11, 18, 32, 0.97);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--card-border);
    padding: 16px 5%;
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.22s ease, opacity 0.22s ease;
  }
  .main-nav.open { transform: none; opacity: 1; pointer-events: auto; }
  .main-nav a { padding: 10px 0; width: 100%; }
  .lang-toggle { margin-top: 8px; }

  .nav-burger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav-burger.open span:nth-child(2) { opacity: 0; }
  .nav-burger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
}