/* ===== Reset & Base ===== */
*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: #f5f5f7;
  background-image:
    radial-gradient(ellipse 60% 50% at 10% 20%, rgba(99,102,241,0.03) 0%, transparent 65%),
    radial-gradient(ellipse 40% 35% at 90% 75%, rgba(168,85,247,0.025) 0%, transparent 55%),
    radial-gradient(ellipse 35% 30% at 50% 5%, rgba(59,130,246,0.02) 0%, transparent 50%);
  background-attachment: fixed;
  color: #1a1a2e;
  line-height: 1.6;
  min-height: 100vh;
}
a { color: inherit; text-decoration: none; }

/* ===== Navbar ===== */
.navbar {
  position: fixed; top:0; left:0; right:0;
  z-index: 100;
  background: rgba(255,255,255,0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
}
.nav-inner {
  max-width: 960px; margin: 0 auto;
  display: flex; align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  height: 56px;
}
.logo {
  font-size: 1.1rem; font-weight: 600;
  letter-spacing: 0.05em;
  color: #1a1a2e;
}
.nav-links { display: flex; gap: 8px; }
.nav-links a {
  padding: 6px 16px;
  border-radius: 8px;
  font-size: 0.9rem;
  color: rgba(0,0,0,0.5);
  transition: all 0.2s;
}
.nav-links a:hover, .nav-links a.active {
  color: #1a1a2e;
  background: rgba(0,0,0,0.05);
}

/* ===== Hero ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(99,102,241,0.05) 0%, transparent 55%),
    radial-gradient(ellipse at 80% 50%, rgba(168,85,247,0.03) 0%, transparent 55%);
}
.hero-content {
  text-align: center;
  position: relative;
  z-index: 1;
  padding: 24px;
}
.avatar {
  width: 80px; height: 80px;
  border-radius: 50%;
  background: linear-gradient(135deg, #6366f1, #a855f7);
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 24px;
}
.avatar-text {
  font-size: 2rem; font-weight: 600;
  color: #fff;
}
.hero-content h1 {
  font-size: 2.5rem;
  font-weight: 700;
  color: #1a1a2e;
  margin-bottom: 8px;
}
.tagline {
  font-size: 1.05rem;
  color: rgba(0,0,0,0.45);
  margin-bottom: 4px;
}
.desc {
  font-size: 0.95rem;
  color: rgba(0,0,0,0.3);
  margin-bottom: 32px;
}
.hero-actions {
  display: flex; gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}
.btn-primary, .btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 12px 28px;
  border-radius: 12px;
  font-size: 0.95rem;
  font-weight: 500;
  transition: all 0.2s;
}
.btn-primary {
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  color: #fff;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(99,102,241,0.3); }
.btn-secondary {
  background: rgba(0,0,0,0.04);
  color: rgba(0,0,0,0.7);
  border: 1px solid rgba(0,0,0,0.08);
}
.btn-secondary:hover { background: rgba(0,0,0,0.07); }

/* ===== Section ===== */
.section {
  padding: 80px 24px;
}
.section-inner {
  max-width: 960px;
  margin: 0 auto;
}
.section h2 {
  font-size: 1.5rem;
  font-weight: 600;
  color: #1a1a2e;
  margin-bottom: 32px;
}

/* ===== Cards ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.card {
  background: #fff;
  border: 1px solid rgba(0,0,0,0.06);
  border-radius: 16px;
  padding: 28px;
  transition: all 0.25s;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}
.card:hover {
  border-color: rgba(99,102,241,0.15);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(99,102,241,0.06);
}
.card-icon {
  font-size: 2rem;
  margin-bottom: 12px;
}
.card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  color: #1a1a2e;
  margin-bottom: 8px;
}
.card p {
  font-size: 0.9rem;
  color: rgba(0,0,0,0.45);
  margin-bottom: 16px;
  line-height: 1.6;
}
.card-link {
  font-size: 0.85rem;
  color: #6366f1;
  font-weight: 500;
}
.card-link:hover { color: #4f46e5; }
.card-tag {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 6px;
  font-size: 0.75rem;
  background: rgba(99,102,241,0.08);
  color: #6366f1;
}

/* ===== Footer ===== */
.footer {
  padding: 24px;
  border-top: 1px solid rgba(0,0,0,0.06);
  text-align: center;
}
.footer p {
  font-size: 0.8rem;
  color: rgba(0,0,0,0.3);
}
.footer .footer-title {
  font-size: 0.85rem;
  color: rgba(0,0,0,0.4);
  margin-bottom: 4px;
}
.footer .footer-beian {
  margin-bottom: 8px;
}
.footer .footer-beian a {
  color: rgba(0,0,0,0.4);
  text-decoration: none;
  font-size: 0.8rem;
}
.footer .footer-beian a:hover {
  color: rgba(0,0,0,0.6);
  text-decoration: underline;
}
.footer .footer-desc {
  font-size: 0.72rem;
  color: rgba(0,0,0,0.25);
  line-height: 1.6;
  max-width: 600px;
  margin: 0 auto;
}

/* ===== Page Header ===== */
.page-header {
  padding-top: 88px;
  text-align: center;
  padding-bottom: 40px;
}
.page-header h1 {
  font-size: 2rem;
  color: #1a1a2e;
  margin-bottom: 8px;
}
.page-header p {
  color: rgba(0,0,0,0.4);
  font-size: 0.95rem;
}

/* ===== Placeholder ===== */
.placeholder {
  text-align: center;
  padding: 80px 24px;
  color: rgba(0,0,0,0.3);
}
.placeholder .icon { font-size: 3rem; margin-bottom: 16px; }
.placeholder p { font-size: 0.95rem; }

/* ===== Responsive ===== */
@media (max-width: 640px) {
  .hero-content h1 { font-size: 1.8rem; }
  .card-grid { grid-template-columns: 1fr; }
  .nav-links a { padding: 6px 12px; font-size: 0.85rem; }
}

/* ===== Dark Mode (全局) ===== */
body.dark-mode {
  background: #1a1a2e;
  background-image: none;
}
body.dark-mode .navbar {
  background: rgba(10,10,25,0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom-color: rgba(255,255,255,0.06);
}
body.dark-mode .logo { color: #e0e0e0; }
body.dark-mode .nav-links a { color: rgba(255,255,255,0.5); }
body.dark-mode .nav-links a:hover,
body.dark-mode .nav-links a.active {
  color: #e0e0e0;
  background: rgba(255,255,255,0.08);
}
body.dark-mode .hero-content h1 { color: #e0e0e0; }
body.dark-mode .hero-content p { color: rgba(255,255,255,0.45); }
body.dark-mode .hero .btn-primary { background: #6366f1; color: #fff; }
body.dark-mode .card { background: #16213e; border-color: rgba(255,255,255,0.06); }
body.dark-mode .card:hover { border-color: rgba(129,140,248,0.3); }
body.dark-mode .card h3 { color: #e0e0e0; }
body.dark-mode .card p { color: rgba(255,255,255,0.45); }
body.dark-mode .card-link,
body.dark-mode .card-link:hover { color: #818cf8; }
body.dark-mode .section-title { color: #e0e0e0; }
body.dark-mode .section-title p,
body.dark-mode .page-header p { color: rgba(255,255,255,0.4); }
body.dark-mode .footer { border-top-color: rgba(255,255,255,0.06); }
body.dark-mode .footer p { color: rgba(255,255,255,0.35); }
body.dark-mode .footer .footer-title { color: rgba(255,255,255,0.55); }
body.dark-mode .footer .footer-beian,
body.dark-mode .footer .footer-beian a { color: rgba(255,255,255,0.35); }