/* =========================================================
   旋风加速器 官方网站 全局样式
   主题：科技蓝 + 渐变，响应式，SEO 友好（无脚本）
   ========================================================= */

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --accent: #06b6d4;
  --accent-2: #22d3ee;
  --dark: #0b1220;
  --dark-2: #0f1a2e;
  --text: #1e293b;
  --muted: #64748b;
  --light: #f8fafc;
  --card-bg: #ffffff;
  --border: #e2e8f0;
  --radius: 16px;
  --shadow: 0 10px 30px rgba(2, 6, 23, 0.08);
  --shadow-lg: 0 20px 50px rgba(2, 6, 23, 0.16);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  color: var(--text);
  background: var(--light);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

.container { max-width: 1160px; margin: 0 auto; padding: 0 20px; }

/* ============ 顶部导航 ============ */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(11, 18, 32, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 68px;
}
.logo {
  display: flex; align-items: center; gap: 10px;
  font-size: 22px; font-weight: 800; color: #fff;
}
.logo .logo-mark {
  width: 38px; height: 38px; border-radius: 10px;
  background: linear-gradient(135deg, var(--accent), var(--primary));
  display: flex; align-items: center; justify-content: center;
  font-size: 20px; color: #fff;
}
.nav { display: flex; align-items: center; gap: 6px; }
.nav a {
  color: #cbd5e1; font-size: 15px; padding: 8px 14px;
  border-radius: 8px; transition: all .2s;
}
.nav a:hover, .nav a.active { color: #fff; background: rgba(255, 255, 255, 0.08); }
.nav .nav-btn {
  margin-left: 8px; padding: 9px 20px; border-radius: 20px;
  background: linear-gradient(135deg, var(--accent), var(--primary));
  color: #fff; font-weight: 700;
}

/* 移动端导航 */
.menu-toggle { display: none; }

/* ============ Hero 主视觉 ============ */
.hero {
  position: relative; overflow: hidden;
  background:
    radial-gradient(900px 500px at 85% -10%, rgba(34, 211, 238, 0.28), transparent 60%),
    radial-gradient(700px 500px at 10% 110%, rgba(37, 99, 235, 0.35), transparent 60%),
    linear-gradient(160deg, #0b1220 0%, #101b33 50%, #12234a 100%);
  color: #fff; padding: 90px 0 100px;
}
.hero-grid {
  display: grid; grid-template-columns: 1.05fr 0.95fr;
  gap: 50px; align-items: center;
}
.hero h1 {
  font-size: 46px; line-height: 1.25; font-weight: 800; margin-bottom: 18px;
}
.hero h1 .grad {
  background: linear-gradient(90deg, var(--accent-2), #60a5fa);
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero .sub {
  font-size: 18px; color: #cbd5e1; max-width: 520px; margin-bottom: 30px;
}
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 14px 30px; border-radius: 30px; font-size: 16px; font-weight: 700;
  transition: all .2s; cursor: pointer;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--primary));
  color: #fff; box-shadow: 0 10px 26px rgba(37, 99, 235, 0.4);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 34px rgba(37, 99, 235, 0.5); }
.btn-ghost { background: rgba(255, 255, 255, 0.08); color: #fff; border: 1px solid rgba(255, 255, 255, 0.2); }
.btn-ghost:hover { background: rgba(255, 255, 255, 0.16); }

/* Hero 视觉面板 */
.hero-visual {
  position: relative; min-height: 360px;
  display: flex; align-items: center; justify-content: center;
}
.hero-orbit {
  position: relative; width: 320px; height: 320px; border-radius: 50%;
  background: conic-gradient(from 0deg, rgba(34, 211, 238, 0.25), rgba(37, 99, 235, 0.25), rgba(34, 211, 238, 0.25));
  display: flex; align-items: center; justify-content: center;
  animation: spin 12s linear infinite;
}
.hero-core {
  width: 150px; height: 150px; border-radius: 50%;
  background: linear-gradient(135deg, #0ea5e9, #2563eb);
  display: flex; align-items: center; justify-content: center;
  font-size: 40px; box-shadow: 0 0 60px rgba(14, 165, 233, 0.7);
}
@keyframes spin { to { transform: rotate(360deg); } }
.hero-node {
  position: absolute; width: 46px; height: 46px; border-radius: 50%;
  background: #fff; display: flex; align-items: center; justify-content: center;
  font-size: 20px; box-shadow: 0 8px 20px rgba(0,0,0,0.3);
}
.node-1 { top: 6px; left: 50%; transform: translateX(-50%); }
.node-2 { bottom: 20px; right: 6px; }
.node-3 { bottom: 20px; left: 6px; }

/* ============ 通用 Section ============ */
.section { padding: 80px 0; }
.section-alt { background: #fff; }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 50px; }
.section-head h2 { font-size: 32px; font-weight: 800; margin-bottom: 12px; }
.section-head p { color: var(--muted); font-size: 16px; }

/* ============ 数据区 ============ */
.stats { background: linear-gradient(135deg, var(--primary), var(--accent)); color: #fff; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; text-align: center; }
.stat-item .num { font-size: 40px; font-weight: 800; }
.stat-item .label { color: rgba(255, 255, 255, 0.85); }

/* ============ 卡片区 ============ */
.cards-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.card {
  background: var(--card-bg); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 30px 26px;
  box-shadow: var(--shadow); transition: all .25s;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.card .icon {
  width: 56px; height: 56px; border-radius: 14px; margin-bottom: 18px;
  display: flex; align-items: center; justify-content: center; font-size: 26px;
  background: linear-gradient(135deg, #eff6ff, #e0f2fe);
}
.card h3 { font-size: 20px; font-weight: 700; margin-bottom: 10px; }
.card p { color: var(--muted); font-size: 15px; }

/* ============ 平台区 ============ */
.platforms { background: var(--dark); color: #fff; }
.platform-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; text-align: center; }
.platform-item {
  background: rgba(255,255,255,0.05); border: 1px solid rgba(255,255,255,0.08);
  border-radius: var(--radius); padding: 34px 20px;
}
.platform-item .picon {
  width: 70px; height: 70px; margin: 0 auto 16px; border-radius: 18px;
  display: flex; align-items: center; justify-content: center; font-size: 32px;
  background: linear-gradient(135deg, var(--accent), var(--primary));
}

/* ============ 步骤区 ============ */
.steps-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.step {
  background: var(--card-bg); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 28px 24px; text-align: center;
  position: relative;
}
.step .step-no {
  width: 44px; height: 44px; margin: 0 auto 14px; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--primary)); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 20px; font-weight: 800;
}

/* ============ FAQ 区 ============ */
.faq-list { max-width: 840px; margin: 0 auto; }
.faq-item {
  background: var(--card-bg); border: 1px solid var(--border);
  border-radius: 14px; margin-bottom: 18px; overflow: hidden;
}
.faq-q {
  padding: 20px 24px; font-size: 17px; font-weight: 700; color: var(--text);
  display: flex; align-items: center; gap: 10px;
}
.faq-q .qtag {
  flex: none; width: 26px; height: 26px; border-radius: 7px;
  background: linear-gradient(135deg, var(--accent), var(--primary)); color: #fff;
  display: inline-flex; align-items: center; justify-content: center; font-size: 14px;
}
.faq-a { padding: 0 24px 22px; color: var(--muted); }
.faq-a ol { padding-left: 20px; }
.faq-a ol li { margin-bottom: 6px; }

/* 分类标签 */
.cat-tabs { display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; margin-bottom: 40px; }
.cat-tab {
  padding: 10px 20px; border-radius: 24px; background: #eef2ff; color: var(--primary);
  font-weight: 600; font-size: 15px; border: 1px solid #dbeafe; transition: all .2s;
}
.cat-tab:hover { background: var(--primary); color: #fff; }

/* ============ 评价区 ============ */
.testi-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.testi {
  background: var(--card-bg); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 26px;
}
.testi .stars { color: #f59e0b; font-size: 18px; margin-bottom: 12px; }
.testi p { color: var(--muted); font-size: 15px; margin-bottom: 14px; }
.testi .user { font-weight: 700; font-size: 14px; }

/* ============ 页面 Hero（内页） ============ */
.page-hero {
  background: linear-gradient(160deg, #0b1220, #12234a);
  color: #fff; padding: 60px 0; text-align: center;
}
.page-hero h1 { font-size: 36px; font-weight: 800; margin-bottom: 10px; }
.page-hero p { color: #cbd5e1; max-width: 640px; margin: 0 auto; }
.breadcrumb { margin-top: 16px; font-size: 14px; color: #94a3b8; }
.breadcrumb a { color: #60a5fa; }

/* ============ 内容页正文 ============ */
.prose { max-width: 860px; margin: 0 auto; }
.prose h2 { font-size: 26px; font-weight: 800; margin: 40px 0 14px; }
.prose h3 { font-size: 20px; font-weight: 700; margin: 26px 0 10px; }
.prose p { color: var(--muted); margin-bottom: 14px; }
.prose ul, .prose ol { color: var(--muted); padding-left: 22px; margin-bottom: 16px; }
.prose li { margin-bottom: 8px; }

/* ============ CTA 区 ============ */
.cta-band {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff; padding: 70px 0; text-align: center;
}
.cta-band h2 { font-size: 32px; font-weight: 800; margin-bottom: 14px; }
.cta-band p { margin-bottom: 28px; color: rgba(255,255,255,0.9); }
.cta-band .btn-white {
  background: #fff; color: var(--primary); padding: 14px 34px;
}

/* ============ 页脚 ============ */
.site-footer { background: var(--dark); color: #94a3b8; padding: 60px 0 30px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand p { font-size: 14px; margin-top: 14px; max-width: 300px; }
.footer-col h4 { color: #fff; font-size: 16px; margin-bottom: 16px; }
.footer-col a { display: block; font-size: 14px; margin-bottom: 10px; transition: color .2s; }
.footer-col a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08); padding-top: 24px;
  font-size: 13px; text-align: center;
}

/* ============ 响应式 ============ */
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-visual { min-height: 260px; }
  .cards-grid, .testi-grid { grid-template-columns: 1fr 1fr; }
  .stats-grid, .platform-grid, .steps-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .nav { display: none; }
}
@media (max-width: 560px) {
  .cards-grid, .testi-grid { grid-template-columns: 1fr; }
  .stats-grid, .platform-grid, .steps-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 32px; }
  .footer-grid { grid-template-columns: 1fr; }
}