/* ==========================================================================
   精灵学院 (Elven Academy Cloud) - riolu443.buzz
   UI 核心规范：秘银钛金微雕 & 精密机械锁合硬件设计系统
   (Micro-engraved mithril-titanium & precision-lock hardware UI design)
   - 绝无通用 AI 火花法杖等低端元素
   - 触感银匠配色：喷砂秘银 (#f1f5f9)、阳极氧化白钛板 (#ffffff)、深林祖母绿指示灯 (#059669)、冷刻岩炭字 (#1e293b)
   - CNC 微雕几何滚花边框、嵌入式等宽遥测仓、各向异性金属光泽、45度机械棘轮阻尼转锁交互
   ========================================================================== */

:root {
  /* 触感银匠基础配色 - 白天模式 (默认) */
  --mithril-base: #f1f5f9;       /* 喷砂秘银底色 */
  --titanium-plate: rgba(255, 255, 255, 0.92);     /* 阳极氧化珍珠钛金板(轻度透光) */
  --titanium-plate-sub: rgba(248, 250, 252, 0.88); /* 次级机加工钛板 */
  --titanium-bay: rgba(237, 242, 247, 0.85);       /* 嵌入式凹槽遥测仓 */

  /* 精灵学院插画背景层参数 (白天透光度与遮罩) */
  --bg-illustration-opacity: 0.38;
  --bg-illustration-filter: saturate(1.15) brightness(1.02);
  --bg-overlay: linear-gradient(180deg, 
    rgba(241, 245, 249, 0.65) 0%, 
    rgba(241, 245, 249, 0.82) 40%, 
    rgba(241, 245, 249, 0.94) 85%, 
    rgba(241, 245, 249, 0.98) 100%
  );
  
  --cnc-engraved-line: rgba(30, 41, 59, 0.12);    /* CNC 激光精雕线条 */
  --cnc-hairline: rgba(30, 41, 59, 0.06);         /* 超微发丝纹 */
  --metallic-sheen: linear-gradient(135deg, rgba(255, 255, 255, 0.9) 0%, rgba(241, 245, 249, 0.7) 50%, rgba(226, 232, 240, 0.5) 100%);
  --plate-bevel: inset 0 1px 0 rgba(255, 255, 255, 0.95), 0 1px 3px rgba(15, 23, 42, 0.05), 0 12px 24px -6px rgba(15, 23, 42, 0.06);
  --plate-bevel-hover: inset 0 1px 0 rgba(255, 255, 255, 1), 0 4px 12px rgba(15, 23, 42, 0.08), 0 20px 32px -8px rgba(15, 23, 42, 0.12);
  
  /* 状态指示与电讯工程色 */
  --emerald-led: #059669;        /* 深林祖母绿指示灯 */
  --emerald-glow: rgba(5, 150, 105, 0.35);
  --emerald-light: #ecfdf5;
  --emerald-border: #a7f3d0;
  
  /*  typography */
  --slate-charcoal: #1e293b;     /* 冷刻岩炭主文字 */
  --slate-body: #475569;         /* 亚光冷灰正文 */
  --slate-muted: #64748b;        /* 工业刻字辅助说明 */
  
  /* 强调色与金属专线色 */
  --telecom-indigo: #4338ca;
  --telecom-gradient: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #334155 100%);
  --brand-titanium-gradient: linear-gradient(135deg, #1e293b 0%, #334155 60%, #059669 100%);
  
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", ui-monospace, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  
  --max-width: 1240px;
  --transition-detent: 0.4s cubic-bezier(0.2, 0.8, 0.2, 1);
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 钛晶黑曜模式 - 夜间模式 (星空插画完美契合) */
[data-theme="dark"] {
  --mithril-base: #090d14;       /* 沉降黑曜底色 */
  --titanium-plate: rgba(17, 24, 35, 0.88);     /* 枪钢微雕面板(通透质感) */
  --titanium-plate-sub: rgba(22, 32, 46, 0.85); /* 哑光锻造钛合金 */
  --titanium-bay: rgba(12, 18, 26, 0.82);       /* 阴刻低照度遥测仓 */
  
  /* 精灵学院插画背景层参数 (暗夜星空绚烂深邃) */
  --bg-illustration-opacity: 0.68;
  --bg-illustration-filter: saturate(1.22) brightness(0.95);
  --bg-overlay: linear-gradient(180deg, 
    rgba(9, 13, 20, 0.52) 0%, 
    rgba(9, 13, 20, 0.76) 40%, 
    rgba(9, 13, 20, 0.92) 85%, 
    rgba(9, 13, 20, 0.98) 100%
  );
  
  --cnc-engraved-line: rgba(255, 255, 255, 0.12);
  --cnc-hairline: rgba(255, 255, 255, 0.05);
  --metallic-sheen: linear-gradient(135deg, rgba(255, 255, 255, 0.08) 0%, rgba(255, 255, 255, 0.02) 50%, transparent 100%);
  --plate-bevel: inset 0 1px 0 rgba(255, 255, 255, 0.14), inset 0 0 0 1px rgba(255, 255, 255, 0.06), 0 16px 36px rgba(0, 0, 0, 0.6);
  --plate-bevel-hover: inset 0 1px 0 rgba(255, 255, 255, 0.28), inset 0 0 0 1px rgba(16, 185, 129, 0.4), 0 20px 40px rgba(0, 0, 0, 0.8);
  
  --emerald-led: #10b981;
  --emerald-glow: rgba(16, 185, 129, 0.5);
  --emerald-light: rgba(16, 185, 129, 0.12);
  --emerald-border: rgba(16, 185, 129, 0.3);
  
  --slate-charcoal: #f8fafc;
  --slate-body: #cbd5e1;
  --slate-muted: #94a3b8;
  
  --telecom-indigo: #6366f1;
  --telecom-gradient: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
  --brand-titanium-gradient: linear-gradient(135deg, #f8fafc 0%, #cbd5e1 50%, #10b981 100%);
}

/* ==========================================================================
   全局重置与微雕背景纹理
   ========================================================================== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  scroll-padding-top: 86px;
}

body {
  font-family: var(--font-sans);
  background-color: var(--mithril-base);
  color: var(--slate-charcoal);
  line-height: 1.6;
  position: relative;
  overflow-x: hidden;
  transition: background-color var(--transition-detent), color var(--transition-detent);
}

/* 精灵学院专属星空插画背景层 (Fixed Atmospheric Illustration Canvas) */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  width: 100vw;
  height: 100vh;
  background-image: url('bg.jpg');
  background-size: cover;
  background-position: center top;
  background-repeat: no-repeat;
  opacity: var(--bg-illustration-opacity);
  filter: var(--bg-illustration-filter);
  pointer-events: none;
  z-index: -2;
  transition: opacity var(--transition-detent), filter var(--transition-detent);
}

/* 保护与微雕层：平滑点阵微雕网格 + 气氛渐变遮罩，确保文字最高级别清晰度 */
body::after {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  width: 100vw;
  height: 100vh;
  background: 
    radial-gradient(var(--cnc-engraved-line) 1px, transparent 1px),
    var(--bg-overlay);
  background-size: 32px 32px, 100% 100%;
  pointer-events: none;
  z-index: -1;
  transition: background var(--transition-detent);
}

a {
  color: inherit;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

/* ==========================================================================
   硬件工业级导航 Header (Precision Telemetry Nav)
   ========================================================================== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 76px;
  background: rgba(241, 245, 249, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--cnc-engraved-line);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.03);
  z-index: 1000;
  transition: all var(--transition-fast);
}

[data-theme="dark"] .header {
  background: rgba(9, 13, 20, 0.88);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
}

.nav-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: 16px;
}

/* 品牌标志：官方 Riolu 443 图形 Logo + 品牌文本 */
.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.brand-logo-img {
  height: 38px;
  width: auto;
  object-fit: contain;
  filter: drop-shadow(0 2px 6px rgba(0, 0, 0, 0.1));
  transition: transform var(--transition-fast);
}

.brand-logo:hover .brand-logo-img {
  transform: scale(1.04);
}

.brand-divider {
  width: 1px;
  height: 26px;
  background: var(--cnc-engraved-line);
}

.brand-text-group {
  display: flex;
  flex-direction: column;
}

.brand-name {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--slate-charcoal);
  line-height: 1.2;
}

.brand-sub {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--emerald-led);
  text-transform: uppercase;
}

/* 导航链接集合 (包含首页 + 每个板块 + 推荐资讯) */
.nav-links {
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-link {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--slate-body);
  padding: 8px 12px;
  border-radius: var(--radius-xs);
  position: relative;
  transition: all var(--transition-fast);
}

.nav-link:hover {
  color: var(--slate-charcoal);
  background: rgba(30, 41, 59, 0.05);
}

[data-theme="dark"] .nav-link:hover {
  background: rgba(255, 255, 255, 0.06);
}

/* 推荐资讯高亮小勋标 */
.nav-link-special {
  color: var(--emerald-led) !important;
  font-weight: 700;
  position: relative;
}

.nav-link-special::before {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--emerald-led);
  margin-right: 6px;
  box-shadow: 0 0 6px var(--emerald-glow);
  vertical-align: middle;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

/* 精工机械微刻昼夜模式切换按钮 */
.theme-toggle-btn {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  color: var(--slate-charcoal);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  position: relative;
  outline: none;
  box-shadow: var(--plate-bevel);
  transition: all var(--transition-fast);
}

.theme-toggle-btn:hover {
  border-color: var(--emerald-led);
  box-shadow: 0 0 0 2px var(--emerald-border);
  transform: translateY(-1px);
}

.theme-toggle-btn svg {
  width: 20px;
  height: 20px;
  transition: transform var(--transition-detent);
}

.theme-toggle-btn:hover svg {
  transform: rotate(45deg);
}

.sun-icon { display: none; }
.moon-icon { display: block; }
[data-theme="dark"] .sun-icon { display: block; stroke: #fbbf24; }
[data-theme="dark"] .moon-icon { display: none; }

/* ==========================================================================
   精密金属按钮系统 (Precision Hardware Button)
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: 0.92rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  border-radius: var(--radius-sm);
  cursor: pointer;
  border: none;
  outline: none;
  transition: all var(--transition-fast);
  white-space: nowrap;
  font-family: var(--font-sans);
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: var(--brand-titanium-gradient);
  color: #ffffff;
  border: 1px solid rgba(0, 0, 0, 0.2);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.25), 0 4px 12px rgba(15, 23, 42, 0.15);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.35), 0 8px 20px rgba(5, 150, 105, 0.25);
  color: #ffffff;
}

.btn-secondary {
  background: var(--titanium-plate);
  color: var(--slate-charcoal);
  border: 1px solid var(--cnc-engraved-line);
  box-shadow: var(--plate-bevel);
}

.btn-secondary:hover {
  border-color: var(--slate-charcoal);
  transform: translateY(-2px);
  background: var(--titanium-plate-sub);
}

.btn-emerald {
  background: linear-gradient(135deg, #059669 0%, #047857 100%);
  color: #ffffff;
  border: 1px solid rgba(5, 150, 105, 0.6);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.25), 0 4px 12px var(--emerald-glow);
}

.btn-emerald:hover {
  background: linear-gradient(135deg, #10b981 0%, #059669 100%);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--emerald-glow);
  color: #ffffff;
}

.btn-lg {
  padding: 14px 30px;
  font-size: 1rem;
}

.btn-sm {
  padding: 8px 16px;
  font-size: 0.85rem;
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   精密机械锁合微交互零件 (Precision Lock-Ring Component)
   - 鼠标悬停卡片时，同心圆锁环以精准机械阻尼旋转 45 度，并点亮深林祖母绿 LED
   ========================================================================== */
.lock-actuator {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.lock-ring-box {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-xs);
  background: var(--titanium-bay);
  border: 1px solid var(--cnc-engraved-line);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  flex-shrink: 0;
  transition: border-color var(--transition-fast);
}

.lock-ring-svg {
  width: 20px;
  height: 20px;
  color: var(--slate-muted);
  transition: transform var(--transition-detent), color var(--transition-detent);
}

.led-indicator {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--slate-muted);
  box-shadow: none;
  transition: all var(--transition-detent);
  position: relative;
}

/* 激活状态 / 悬停联动：锁环顺时针旋转45°，点亮祖母绿 LED */
.feature-card:hover .lock-ring-svg,
.special-card:hover .lock-ring-svg,
.pricing-card:hover .lock-ring-svg,
.hardware-plate:hover .lock-ring-svg {
  transform: rotate(45deg);
  color: var(--emerald-led);
}

.feature-card:hover .led-indicator,
.special-card:hover .led-indicator,
.pricing-card:hover .led-indicator,
.hardware-plate:hover .led-indicator {
  background: var(--emerald-led);
  box-shadow: 0 0 10px var(--emerald-led);
}

/* ==========================================================================
   等宽遥测仓 (Recessed Monospace Telemetry Bay)
   ========================================================================== */
.telemetry-bay {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  background: var(--titanium-bay);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-xs);
  padding: 8px 12px;
  color: var(--slate-muted);
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 14px;
  letter-spacing: 0.04em;
}

.telemetry-tag {
  color: var(--emerald-led);
  font-weight: 700;
}

/* ==========================================================================
   Hero 主视觉区 (醒目标题含品牌名 + 详细简介 + 遥测仪器群)
   ========================================================================== */
.hero {
  padding: 165px 0 90px;
  text-align: center;
  position: relative;
}

.hero-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  box-shadow: var(--plate-bevel);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--slate-body);
  margin-bottom: 26px;
}

.hero-title {
  font-size: 3.4rem;
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: -0.03em;
  margin-bottom: 22px;
  max-width: 980px;
  margin-left: auto;
  margin-right: auto;
}

.hero-title .brand-highlight {
  color: var(--slate-charcoal);
  border-bottom: 3px solid var(--emerald-led);
  padding-bottom: 2px;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--slate-body);
  max-width: 760px;
  margin: 0 auto 38px;
  line-height: 1.75;
}

.hero-cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  margin-bottom: 54px;
  flex-wrap: wrap;
}

/* 遥测指标组 (CNC 金属嵌板) */
.hero-telemetry-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 1040px;
  margin: 0 auto;
}

.telemetry-plate {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-sm);
  padding: 20px 16px;
  box-shadow: var(--plate-bevel);
  text-align: left;
  transition: all var(--transition-fast);
  position: relative;
}

/* 毛玻璃半透光质感：使背景星空插画在钛金面板后自然折射透现 */
.telemetry-plate,
.feature-card,
.special-card,
.pricing-card,
.testimonial-card,
.faq-item,
.bottom-cta-box,
.sitemap-card,
.article-card {
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.telemetry-plate:hover {
  border-color: var(--emerald-led);
  transform: translateY(-2px);
}

.telemetry-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--slate-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 6px;
  display: block;
}

.telemetry-val {
  font-size: 1.7rem;
  font-weight: 900;
  color: var(--slate-charcoal);
  font-family: var(--font-sans);
  line-height: 1.1;
  display: block;
}

.telemetry-note {
  font-size: 0.78rem;
  color: var(--emerald-led);
  margin-top: 4px;
  font-weight: 600;
  display: block;
}

/* ==========================================================================
   通配板块布局与金属微雕标题
   ========================================================================== */
.section {
  padding: 90px 0;
  position: relative;
}

.section-alt {
  background-color: var(--titanium-plate-sub);
  border-top: 1px solid var(--cnc-engraved-line);
  border-bottom: 1px solid var(--cnc-engraved-line);
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 56px;
}

.section-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--emerald-led);
  background: var(--emerald-light);
  border: 1px solid var(--emerald-border);
  padding: 4px 14px;
  border-radius: var(--radius-full);
  margin-bottom: 14px;
  text-transform: uppercase;
}

.section-title {
  font-size: 2.35rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
  color: var(--slate-charcoal);
}

.section-desc {
  font-size: 1.05rem;
  color: var(--slate-body);
  line-height: 1.7;
}

/* ==========================================================================
   产品核心优势介绍 (3个图文钛板卡片)
   ========================================================================== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-md);
  padding: 34px 28px;
  box-shadow: var(--plate-bevel);
  transition: all var(--transition-fast);
  display: flex;
  flex-direction: column;
  position: relative;
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: var(--emerald-led);
  box-shadow: var(--plate-bevel-hover);
}

.card-top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 22px;
}

.feature-icon-metal {
  width: 50px;
  height: 50px;
  border-radius: var(--radius-sm);
  background: var(--titanium-bay);
  border: 1px solid var(--cnc-engraved-line);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--slate-charcoal);
}

.feature-icon-metal svg {
  width: 26px;
  height: 26px;
}

.feature-title {
  font-size: 1.3rem;
  font-weight: 800;
  margin-bottom: 12px;
  color: var(--slate-charcoal);
  letter-spacing: -0.01em;
}

.feature-desc {
  font-size: 0.95rem;
  color: var(--slate-body);
  line-height: 1.7;
  margin-bottom: 22px;
  flex-grow: 1;
}

/* ==========================================================================
   流媒体图卡 & AI 支持图卡 (精密双列硬件展台)
   ========================================================================== */
.special-cards-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.special-card {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-md);
  padding: 36px 32px;
  box-shadow: var(--plate-bevel);
  transition: all var(--transition-fast);
  display: flex;
  flex-direction: column;
}

.special-card:hover {
  transform: translateY(-5px);
  border-color: var(--emerald-led);
  box-shadow: var(--plate-bevel-hover);
}

.special-card-title {
  font-size: 1.45rem;
  font-weight: 800;
  margin-bottom: 8px;
  color: var(--slate-charcoal);
}

.special-card-sub {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--emerald-led);
  font-weight: 600;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
  display: block;
}

.special-card-desc {
  font-size: 0.96rem;
  color: var(--slate-body);
  line-height: 1.7;
  margin-bottom: 26px;
}

.platform-badges-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-top: auto;
}

.platform-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  background: var(--titanium-bay);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-xs);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--slate-charcoal);
  transition: all var(--transition-fast);
}

.platform-badge:hover {
  background: var(--titanium-plate);
  border-color: var(--emerald-led);
  transform: translateY(-1px);
}

.platform-badge svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

/* ==========================================================================
   套餐价格对比表 (参考网上真实机场加速器套餐定价)
   - 真实参考区间：月付~¥12-18, 季付~¥36-48, 年付~¥128-168
   ========================================================================== */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.pricing-card {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-md);
  padding: 38px 28px;
  box-shadow: var(--plate-bevel);
  transition: all var(--transition-fast);
  display: flex;
  flex-direction: column;
  position: relative;
}

.pricing-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--plate-bevel-hover);
}

.pricing-card.featured {
  border-color: var(--emerald-led);
  box-shadow: 0 0 0 2px var(--emerald-led), var(--plate-bevel-hover);
}

.pricing-stamp {
  position: absolute;
  top: -13px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--emerald-led);
  color: #ffffff;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  padding: 3px 14px;
  border-radius: var(--radius-full);
  box-shadow: 0 2px 8px var(--emerald-glow);
  text-transform: uppercase;
}

.pricing-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 10px;
}

.pricing-name {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--slate-charcoal);
}

.pricing-code {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--slate-muted);
}

.pricing-desc {
  font-size: 0.88rem;
  color: var(--slate-body);
  margin-bottom: 22px;
  min-height: 40px;
}

.pricing-price-wrap {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--cnc-engraved-line);
}

.pricing-currency {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--slate-charcoal);
}

.pricing-number {
  font-size: 3rem;
  font-weight: 900;
  color: var(--slate-charcoal);
  line-height: 1;
  font-family: var(--font-sans);
}

.pricing-cycle {
  font-size: 0.88rem;
  color: var(--slate-muted);
  font-weight: 600;
}

.pricing-specs {
  display: flex;
  flex-direction: column;
  gap: 13px;
  margin-bottom: 30px;
  flex-grow: 1;
}

.pricing-spec-item {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--slate-body);
}

.pricing-spec-item svg {
  width: 17px;
  height: 17px;
  color: var(--emerald-led);
  flex-shrink: 0;
}

.pricing-spec-item.disabled {
  color: var(--slate-muted);
  text-decoration: line-through;
  opacity: 0.55;
}

.pricing-spec-item.disabled svg {
  color: var(--slate-muted);
}

/* ==========================================================================
   真实用户评价 (Precision Hardware Review Cards)
   ========================================================================== */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.testimonial-card {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-sm);
  padding: 30px 24px;
  box-shadow: var(--plate-bevel);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all var(--transition-fast);
}

.testimonial-card:hover {
  border-color: var(--emerald-led);
  transform: translateY(-3px);
}

.review-stars {
  display: flex;
  gap: 4px;
  color: #eab308;
  margin-bottom: 16px;
}

.review-stars svg {
  width: 16px;
  height: 16px;
  fill: currentColor;
}

.review-quote {
  font-size: 0.94rem;
  color: var(--slate-body);
  line-height: 1.7;
  margin-bottom: 22px;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.author-chip {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-xs);
  background: var(--titanium-bay);
  border: 1px solid var(--cnc-engraved-line);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-family: var(--font-mono);
  color: var(--emerald-led);
}

.author-name {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--slate-charcoal);
}

.author-role {
  font-size: 0.78rem;
  color: var(--slate-muted);
  font-family: var(--font-mono);
}

/* ==========================================================================
   常见问题解答 (FAQ)
   ========================================================================== */
.faq-wrap {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-sm);
  box-shadow: var(--plate-bevel);
  overflow: hidden;
  transition: all var(--transition-fast);
}

.faq-item:hover {
  border-color: var(--slate-charcoal);
}

.faq-item[open] {
  border-color: var(--emerald-led);
}

.faq-summary {
  padding: 20px 24px;
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--slate-charcoal);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  list-style: none;
}

.faq-summary::-webkit-details-marker {
  display: none;
}

.faq-arrow {
  width: 18px;
  height: 18px;
  color: var(--slate-muted);
  transition: transform var(--transition-fast);
}

.faq-item[open] .faq-arrow {
  transform: rotate(180deg);
  color: var(--emerald-led);
}

.faq-body {
  padding: 0 24px 22px;
  font-size: 0.95rem;
  color: var(--slate-body);
  line-height: 1.75;
}

/* ==========================================================================
   底部呼吁横幅 (Bottom Telemetry CTA)
   ========================================================================== */
.bottom-cta-box {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-md);
  padding: 56px 40px;
  box-shadow: var(--plate-bevel-hover);
  text-align: center;
  margin-top: 40px;
  position: relative;
}

.bottom-cta-title {
  font-size: 2.2rem;
  font-weight: 900;
  color: var(--slate-charcoal);
  margin-bottom: 14px;
}

.bottom-cta-sub {
  font-size: 1.05rem;
  color: var(--slate-body);
  max-width: 640px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

/* ==========================================================================
   页脚规范 Footer (严格仅保留 4 个标题，并在新标签页中打开)
   ========================================================================== */
.footer {
  background-color: var(--titanium-plate-sub);
  border-top: 1px solid var(--cnc-engraved-line);
  padding: 50px 0 36px;
  margin-top: 80px;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.footer-link {
  font-size: 1rem;
  font-weight: 700;
  color: var(--slate-charcoal);
  transition: color var(--transition-fast);
  padding: 4px 8px;
  letter-spacing: 0.02em;
}

.footer-link:hover {
  color: var(--emerald-led);
}

.footer-meta {
  text-align: center;
  font-size: 0.82rem;
  color: var(--slate-muted);
  border-top: 1px solid var(--cnc-engraved-line);
  padding-top: 24px;
  font-family: var(--font-mono);
}

/* ==========================================================================
   资讯列表与内容页特定排版 (Insights & Articles)
   ========================================================================== */
.article-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 26px;
  margin-top: 36px;
}

.article-card {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-sm);
  padding: 30px;
  box-shadow: var(--plate-bevel);
  display: flex;
  flex-direction: column;
  transition: all var(--transition-fast);
}

.article-card:hover {
  border-color: var(--emerald-led);
  transform: translateY(-4px);
  box-shadow: var(--plate-bevel-hover);
}

.article-date {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--emerald-led);
  margin-bottom: 8px;
  font-weight: 700;
}

.article-heading {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--slate-charcoal);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-excerpt {
  font-size: 0.92rem;
  color: var(--slate-body);
  line-height: 1.65;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-read-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--emerald-led);
}

.article-read-more:hover {
  transform: translateX(4px);
}

/* ==========================================================================
   独立子页面通用内容排版 (About / Terms / Privacy / Sitemap)
   ========================================================================== */
.page-hero {
  padding: 140px 0 54px;
  text-align: center;
  border-bottom: 1px solid var(--cnc-engraved-line);
  background: var(--titanium-plate-sub);
}

.page-title {
  font-size: 2.6rem;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--slate-charcoal);
  margin-bottom: 14px;
}

.page-subtitle {
  font-size: 1.1rem;
  color: var(--slate-body);
  max-width: 720px;
  margin: 0 auto;
}

.article-content {
  padding: 60px 0;
  max-width: 880px;
  margin: 0 auto;
}

.content-block {
  margin-bottom: 48px;
}

.content-block h2 {
  font-size: 1.55rem;
  font-weight: 800;
  margin-bottom: 18px;
  color: var(--slate-charcoal);
  display: flex;
  align-items: center;
  gap: 12px;
}

.content-block h2 svg {
  color: var(--emerald-led);
  width: 24px;
  height: 24px;
}

.content-block p {
  color: var(--slate-body);
  line-height: 1.8;
  margin-bottom: 14px;
  font-size: 0.98rem;
}

.content-block ul {
  padding-left: 20px;
  list-style: disc;
  color: var(--slate-body);
  margin-bottom: 16px;
}

.content-block li {
  margin-bottom: 8px;
  line-height: 1.7;
}

.info-alert {
  background: var(--emerald-light);
  border-left: 4px solid var(--emerald-led);
  border-radius: var(--radius-xs);
  padding: 18px 22px;
  margin: 22px 0;
  color: var(--slate-charcoal);
  font-size: 0.95rem;
  line-height: 1.65;
}

.danger-alert {
  background: rgba(239, 68, 68, 0.08);
  border-left: 4px solid #ef4444;
  border-radius: var(--radius-xs);
  padding: 18px 22px;
  margin: 22px 0;
  color: var(--slate-charcoal);
  font-size: 0.95rem;
  line-height: 1.65;
}

.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 30px;
}

.sitemap-card {
  background: var(--titanium-plate);
  border: 1px solid var(--cnc-engraved-line);
  border-radius: var(--radius-sm);
  padding: 28px;
  box-shadow: var(--plate-bevel);
}

.sitemap-card h3 {
  font-size: 1.25rem;
  margin-bottom: 16px;
  color: var(--slate-charcoal);
}

.sitemap-card ul {
  list-style: none;
  padding: 0;
}

.sitemap-card li {
  margin-bottom: 12px;
}

.sitemap-card a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--slate-body);
  font-weight: 600;
}

.sitemap-card a:hover {
  color: var(--emerald-led);
  transform: translateX(4px);
}

/* ==========================================================================
   响应式媒体查询 (@media) - 确保手机端单栏显示与手指触控
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 2.75rem;
  }
  
  .features-grid,
  .pricing-grid,
  .testimonials-grid,
  .article-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .special-cards-grid {
    grid-template-columns: 1fr;
  }
  
  .hero-telemetry-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .header {
    height: 68px;
  }
  
  .nav-links {
    display: none; /* 移动端抽离为极简模式 */
  }
  
  .hero {
    padding: 115px 0 60px;
  }
  
  .hero-title {
    font-size: 2.1rem;
    line-height: 1.25;
  }
  
  .hero-subtitle {
    font-size: 1.02rem;
    margin-bottom: 30px;
  }
  
  .hero-cta {
    flex-direction: column;
    width: 100%;
  }
  
  .hero-cta .btn {
    width: 100%;
    min-height: 48px;
  }
  
  .features-grid,
  .special-cards-grid,
  .pricing-grid,
  .testimonials-grid,
  .sitemap-grid,
  .article-grid {
    grid-template-columns: 1fr; /* 移动端完全单栏展示 */
    gap: 20px;
  }
  
  .hero-telemetry-grid {
    grid-template-columns: 1fr;
  }
  
  .platform-badges-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .section {
    padding: 60px 0;
  }
  
  .section-title {
    font-size: 1.85rem;
  }
  
  .bottom-cta-box {
    padding: 40px 20px;
  }
  
  .bottom-cta-title {
    font-size: 1.75rem;
  }
  
  .footer-nav {
    flex-direction: column;
    gap: 16px;
  }
  
  .footer-link {
    font-size: 1.05rem;
    padding: 8px 16px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.78rem;
  }
  
  .platform-badges-grid {
    grid-template-columns: 1fr;
  }
}