/* ===== 全局重置与变量 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --primary:   #0057FF;
  --primary-d: #0040CC;
  --accent:    #00C6FF;
  --dark:      #0A0F1E;
  --dark2:     #111827;
  --card-bg:   #161D2F;
  --text:      #E8EDF8;
  --muted:     #8A93A8;
  --border:    rgba(255,255,255,0.08);
  --radius:    12px;
  --shadow:    0 8px 40px rgba(0,87,255,0.18);
  --transition: 0.3s ease;
}

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
  background: var(--dark);
  color: var(--text);
  line-height: 1.7;
  min-height: 100vh;
}

a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }

/* ===== 滚动条 ===== */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--dark2); }
::-webkit-scrollbar-thumb { background: var(--primary); border-radius: 3px; }

/* ===== 顶部导航 ===== */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 999;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 6%;
  height: 70px;
  background: rgba(10,15,30,0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}

.logo {
  display: flex; align-items: center; gap: 10px;
  font-size: 1.1rem; font-weight: 700; white-space: nowrap;
}
.logo-icon {
  width: 36px; height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.1rem; font-weight: 900; color: #fff;
}
.logo span { color: var(--accent); }

.nav-links { display: flex; gap: 36px; }
.nav-links a {
  font-size: 0.95rem; color: var(--muted);
  transition: color var(--transition);
  position: relative; padding-bottom: 4px;
}
.nav-links a::after {
  content: ""; position: absolute; bottom: 0; left: 0;
  width: 0; height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transition: width var(--transition);
}
.nav-links a:hover, .nav-links a.active { color: var(--text); }
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }

.nav-cta {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff !important;
  padding: 8px 22px; border-radius: 24px;
  font-size: 0.9rem; font-weight: 600;
  transition: opacity var(--transition), transform var(--transition);
}
.nav-cta:hover { opacity: 0.88; transform: translateY(-1px); }
.nav-cta::after { display: none !important; }

/* ===== 通用容器 ===== */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ===== 通用段落标题 ===== */
.section-tag {
  display: inline-block;
  font-size: 0.78rem; font-weight: 700; letter-spacing: 2px; text-transform: uppercase;
  color: var(--accent); background: rgba(0,198,255,0.1);
  padding: 4px 14px; border-radius: 20px; margin-bottom: 14px;
}
.section-title {
  font-size: clamp(1.8rem, 3vw, 2.6rem);
  font-weight: 800; line-height: 1.25;
  margin-bottom: 18px;
}
.section-title span { color: var(--accent); }
.section-desc {
  font-size: 1.05rem; color: var(--muted); max-width: 560px;
}
.section-head { text-align: center; margin-bottom: 60px; }
.section-head .section-desc { margin: 0 auto; }

/* ===== 按钮 ===== */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 32px; border-radius: 32px;
  font-size: 1rem; font-weight: 600; cursor: pointer;
  transition: all var(--transition); border: none;
}
.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  box-shadow: 0 4px 24px rgba(0,87,255,0.35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 32px rgba(0,87,255,0.5); }
.btn-outline {
  background: transparent; color: var(--text);
  border: 1.5px solid rgba(255,255,255,0.25);
}
.btn-outline:hover { border-color: var(--accent); color: var(--accent); }

/* ===== 卡片 ===== */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}
.card:hover {
  transform: translateY(-6px);
  border-color: rgba(0,87,255,0.4);
  box-shadow: var(--shadow);
}

/* ===== 分割线装饰 ===== */
.divider {
  width: 60px; height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 2px; margin: 0 auto 20px;
}

/* ===== Footer ===== */
footer {
  background: #07090F;
  border-top: 1px solid var(--border);
  padding: 60px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}
.footer-brand p { color: var(--muted); font-size: 0.92rem; margin-top: 16px; line-height: 1.8; }
.footer-col h4 { font-size: 0.95rem; font-weight: 700; margin-bottom: 18px; }
.footer-col ul { list-style: none; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { color: var(--muted); font-size: 0.9rem; transition: color var(--transition); }
.footer-col ul li a:hover { color: var(--accent); }
.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 24px;
  display: flex; justify-content: space-between; align-items: center;
  font-size: 0.85rem; color: var(--muted);
}

/* ===== 页面顶部占位 ===== */
.page-top { padding-top: 70px; }

/* ===== 工具类 ===== */
.text-gradient {
  background: linear-gradient(135deg, #fff 20%, var(--accent));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.mt-8 { margin-top: 32px; }
.mt-6 { margin-top: 24px; }
.mt-4 { margin-top: 16px; }
.flex { display: flex; }
.gap-4 { gap: 16px; }
.items-center { align-items: center; }

/* ===== 动画 ===== */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(30px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50%       { transform: translateY(-12px); }
}
@keyframes pulse-ring {
  0%   { transform: scale(0.8); opacity: 0.8; }
  100% { transform: scale(1.6); opacity: 0; }
}
.animate-fade-up { animation: fadeUp 0.8s ease forwards; }
.animate-float   { animation: float 4s ease-in-out infinite; }

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .nav-links { display: none; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 600px) {
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
}