/* ==========================================================================
   肥猫云 FatCatCloud - 98｜全息水晶 (Holographic Crystal) 主题样式表
   特性：全息晶体折射光斑、精简数据排版、实色阅读卡片、完备无障碍与响应式
   ========================================================================== */

:root {
  /* 全息水晶基色系 */
  --bg-dark: #070a14;
  --bg-card: #0d1527;
  --bg-card-solid: #0f182d;
  --bg-card-alt: #131e38;
  --bg-glass: rgba(13, 21, 39, 0.85);

  /* 折射光色板 (Prismatic Refraction) */
  --crystal-cyan: #00f2fe;
  --crystal-blue: #4facfe;
  --crystal-violet: #9b72ff;
  --crystal-magenta: #f355a0;
  --crystal-emerald: #00f5a0;
  --crystal-border: rgba(110, 168, 254, 0.22);
  --crystal-border-hover: rgba(0, 242, 254, 0.5);

  /* 文本对比色 (WCAG AAA 高可读性) */
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --text-accent: #38bdf8;

  /* 字体族 */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-mono: 'SF Mono', 'Cascadia Code', Consolas, Monaco, 'Courier New', monospace;

  /* 容器与安全留白 */
  --container-max: 1200px;
  --header-height: 72px;
  --touch-target: 44px;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;

  /* 全息光晕阴影 */
  --shadow-crystal: 0 10px 30px -10px rgba(0, 242, 254, 0.15), 0 0 1px 1px rgba(255, 255, 255, 0.08);
  --shadow-crystal-glow: 0 0 40px -10px rgba(155, 114, 255, 0.35);
}

/* 基础重置 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body,
body.theme-holographic-crystal {
  font-family: var(--font-sans);
  background-color: var(--bg-dark);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
  word-break: break-word;
}

/* 顶部全息环境光晕（渐进增强，不影响阅读） */
.crystal-ambient-glow {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 600px;
  pointer-events: none;
  z-index: 0;
  background: 
    radial-gradient(circle at 20% 15%, rgba(0, 242, 254, 0.08) 0%, transparent 40%),
    radial-gradient(circle at 80% 10%, rgba(155, 114, 255, 0.09) 0%, transparent 45%),
    radial-gradient(circle at 50% 30%, rgba(243, 85, 160, 0.04) 0%, transparent 50%);
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 20px;
  position: relative;
  z-index: 1;
}

/* 链接基础样式 */
a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease;
}

a:focus-visible, button:focus-visible {
  outline: 2px solid var(--crystal-cyan);
  outline-offset: 3px;
}

/* ==========================================================================
   导航头部 Header
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  height: var(--header-height);
  background: rgba(7, 10, 20, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--crystal-border);
  display: flex;
  align-items: center;
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* 品牌 Logo */
.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: var(--touch-target);
}

.crystal-logo-mark {
  width: 34px;
  height: 34px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(0, 242, 254, 0.2), rgba(155, 114, 255, 0.2));
  border: 1px solid var(--crystal-cyan);
  border-radius: 8px;
  transform: rotate(45deg);
  box-shadow: 0 0 15px rgba(0, 242, 254, 0.3);
}

.prism-facet {
  width: 16px;
  height: 16px;
  background: linear-gradient(135deg, #00f2fe, #9b72ff);
  border-radius: 3px;
  display: block;
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-text .brand-name {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  background: linear-gradient(90deg, #ffffff 40%, var(--crystal-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo-text .brand-sub {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  letter-spacing: 1px;
}

/* 桌面导航 */
.desktop-nav {
  display: none;
}

@media (min-width: 900px) {
  .desktop-nav {
    display: block;
  }
}

.nav-list {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 8px;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  min-height: var(--touch-target);
  padding: 8px 14px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: all 0.2s ease;
}

.nav-link:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.05);
}

.nav-link.active {
  color: var(--crystal-cyan);
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid rgba(0, 242, 254, 0.2);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* 按钮规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: var(--touch-target);
  padding: 10px 22px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  text-align: center;
  white-space: nowrap;
}

.btn-crystal-primary {
  background: linear-gradient(135deg, #00d2ff 0%, #3a7bd5 50%, #9b72ff 100%);
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.3);
  box-shadow: 0 4px 20px rgba(0, 210, 255, 0.35);
}

.btn-crystal-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 25px rgba(0, 210, 255, 0.5);
  border-color: #ffffff;
}

.btn-crystal-secondary {
  background: var(--bg-card-alt);
  color: var(--text-primary);
  border: 1px solid var(--crystal-border);
}

.btn-crystal-secondary:hover {
  border-color: var(--crystal-cyan);
  color: var(--crystal-cyan);
  background: rgba(13, 21, 39, 0.95);
}

.btn-block {
  width: 100%;
}

/* 移动端菜单按钮 */
.mobile-toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: var(--touch-target);
  height: var(--touch-target);
  background: transparent;
  border: 1px solid var(--crystal-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
}

@media (min-width: 900px) {
  .mobile-toggle {
    display: none;
  }
}

.toggle-bar {
  width: 20px;
  height: 2px;
  background-color: var(--text-primary);
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.mobile-toggle.active .toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.mobile-toggle.active .toggle-bar:nth-child(2) {
  opacity: 0;
}
.mobile-toggle.active .toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* 移动端抽屉 */
.mobile-nav {
  position: absolute;
  top: var(--header-height);
  left: 0;
  right: 0;
  background: rgba(7, 10, 20, 0.98);
  border-bottom: 1px solid var(--crystal-border);
  display: none;
  padding: 20px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.7);
}

.mobile-nav.open {
  display: block;
}

.mobile-nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.mobile-nav-list .nav-link {
  width: 100%;
  padding: 12px 16px;
  font-size: 1.05rem;
  border-radius: var(--radius-md);
}

.mobile-cta-wrap {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--crystal-border);
}

/* ==========================================================================
   面包屑 Breadcrumbs
   ========================================================================== */
.breadcrumb-container {
  padding: 14px 0;
  background: rgba(13, 21, 39, 0.4);
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  list-style: none;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.breadcrumb-item a {
  color: var(--text-secondary);
}

.breadcrumb-item a:hover {
  color: var(--crystal-cyan);
}

.breadcrumb-item.active {
  color: var(--text-muted);
}

.breadcrumb-sep {
  color: rgba(255, 255, 255, 0.2);
  user-select: none;
}

/* ==========================================================================
   通用板块布局与徽章
   ========================================================================== */
.section {
  padding: 60px 0;
  position: relative;
}

@media (min-width: 768px) {
  .section {
    padding: 85px 0;
  }
}

.section-alt {
  background: rgba(13, 21, 39, 0.5);
  border-top: 1px solid rgba(255, 255, 255, 0.03);
  border-bottom: 1px solid rgba(255, 255, 255, 0.03);
}

.section-header {
  text-align: center;
  max-width: 800px;
  margin: 0 auto 48px auto;
}

.crystal-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  font-size: 0.82rem;
  font-family: var(--font-mono);
  font-weight: 600;
  border-radius: 999px;
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid rgba(0, 242, 254, 0.3);
  color: var(--crystal-cyan);
  margin-bottom: 16px;
  letter-spacing: 0.5px;
}

.crystal-badge.violet {
  background: rgba(155, 114, 255, 0.08);
  border-color: rgba(155, 114, 255, 0.35);
  color: var(--crystal-violet);
}

.crystal-badge.emerald {
  background: rgba(0, 245, 160, 0.08);
  border-color: rgba(0, 245, 160, 0.35);
  color: var(--crystal-emerald);
}

.section-title {
  font-size: 1.85rem;
  font-weight: 700;
  line-height: 1.35;
  color: #ffffff;
  margin-bottom: 14px;
}

@media (min-width: 768px) {
  .section-title {
    font-size: 2.35rem;
  }
}

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

/* ==========================================================================
   首页 Hero 首屏 (全息水晶主视觉)
   ========================================================================== */
.hero-crystal {
  padding: 60px 0 50px 0;
  position: relative;
  overflow: hidden;
}

@media (min-width: 768px) {
  .hero-crystal {
    padding: 95px 0 75px 0;
  }
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  align-items: center;
}

@media (min-width: 992px) {
  .hero-grid {
    grid-template-columns: 1.15fr 0.85fr;
    gap: 60px;
  }
}

.hero-content {
  text-align: left;
}

.hero-title {
  font-size: 2.2rem;
  font-weight: 800;
  line-height: 1.25;
  color: #ffffff;
  margin-bottom: 20px;
  letter-spacing: -0.5px;
}

@media (min-width: 768px) {
  .hero-title {
    font-size: 3.1rem;
  }
}

.hero-title .text-gradient {
  background: linear-gradient(135deg, #00f2fe 0%, #4facfe 50%, #b088ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.12rem;
  color: var(--text-secondary);
  line-height: 1.75;
  margin-bottom: 30px;
  max-width: 620px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 35px;
}

/* 信任背书栏目 */
.hero-trust-bar {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  padding-top: 24px;
  border-top: 1px solid var(--crystal-border);
}

@media (min-width: 640px) {
  .hero-trust-bar {
    grid-template-columns: repeat(4, 1fr);
  }
}

.trust-item {
  font-size: 0.84rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 6px;
}

.trust-icon {
  color: var(--crystal-cyan);
  font-weight: 700;
}

/* 全息晶体视觉卡片 (Hero Visual Card) */
.crystal-prism-card {
  position: relative;
  background: var(--bg-card-solid);
  border: 1px solid var(--crystal-border);
  border-radius: var(--radius-xl);
  padding: 30px;
  box-shadow: var(--shadow-crystal), var(--shadow-crystal-glow);
  overflow: hidden;
}

/* 折射光纹饰 */
.crystal-prism-card::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 50% 50%, rgba(0, 242, 254, 0.08) 0%, transparent 60%);
  pointer-events: none;
}

.prism-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.prism-title {
  font-size: 1rem;
  font-weight: 600;
  color: #ffffff;
  display: flex;
  align-items: center;
  gap: 8px;
}

.status-indicator {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8rem;
  font-family: var(--font-mono);
  color: var(--crystal-emerald);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--crystal-emerald);
  box-shadow: 0 0 8px var(--crystal-emerald);
}

/* 核心四维指标微型卡片网格 */
.metrics-mini-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}

.metric-mini-card {
  background: var(--bg-card-alt);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-md);
  padding: 16px;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.metric-mini-card:hover {
  transform: translateY(-2px);
  border-color: var(--crystal-border-hover);
}

.metric-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.metric-value {
  font-size: 1.45rem;
  font-family: var(--font-mono);
  font-weight: 700;
  color: #ffffff;
}

.metric-unit {
  font-size: 0.85rem;
  color: var(--crystal-cyan);
  margin-left: 2px;
}

.metric-desc {
  font-size: 0.76rem;
  color: var(--text-muted);
  margin-top: 4px;
}

/* 晶体卡片底部注解 */
.prism-card-note {
  margin-top: 20px;
  padding: 12px 14px;
  background: rgba(0, 0, 0, 0.25);
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  color: var(--text-muted);
  border-left: 3px solid var(--crystal-cyan);
}

/* ==========================================================================
   交互式网络指标解释器 (Practical Function)
   ========================================================================== */
.explainer-container {
  background: var(--bg-card-solid);
  border: 1px solid var(--crystal-border);
  border-radius: var(--radius-xl);
  padding: 30px;
  box-shadow: var(--shadow-crystal);
}

@media (max-width: 640px) {
  .explainer-container {
    padding: 20px;
  }
}

.explainer-banner {
  background: rgba(0, 242, 254, 0.06);
  border: 1px solid rgba(0, 242, 254, 0.2);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  margin-bottom: 30px;
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.banner-icon {
  font-size: 1.25rem;
  color: var(--crystal-cyan);
}

.banner-text {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.banner-text strong {
  color: #ffffff;
}

.explainer-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
}

@media (min-width: 992px) {
  .explainer-layout {
    grid-template-columns: 1fr 1fr;
  }
}

.controls-panel {
  display: flex;
  flex-direction: column;
  gap: 22px;
}

.control-group {
  background: var(--bg-card-alt);
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-md);
  padding: 18px 20px;
}

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

.control-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: #ffffff;
}

.control-value-badge {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--crystal-cyan);
}

.slider-input {
  width: 100%;
  height: 6px;
  -webkit-appearance: none;
  background: rgba(255, 255, 255, 0.12);
  border-radius: 4px;
  outline: none;
  margin: 12px 0 8px 0;
  cursor: pointer;
}

.slider-input::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: linear-gradient(135deg, #00f2fe, #9b72ff);
  box-shadow: 0 0 10px rgba(0, 242, 254, 0.6);
  cursor: pointer;
  border: 2px solid #ffffff;
}

.slider-scale {
  display: flex;
  justify-content: space-between;
  font-size: 0.72rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
}

.control-help {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 6px;
  line-height: 1.5;
}

/* 动态仿真结果展示区 */
.simulation-panel {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.scenario-card {
  background: var(--bg-card-alt);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  padding: 20px;
  transition: all 0.25s ease;
  position: relative;
  overflow: hidden;
}

.scenario-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.scenario-name {
  font-size: 1rem;
  font-weight: 600;
  color: #ffffff;
  display: flex;
  align-items: center;
  gap: 8px;
}

.impact-badge {
  font-size: 0.75rem;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-family: var(--font-mono);
}

.impact-badge.optimum {
  background: rgba(0, 245, 160, 0.15);
  color: var(--crystal-emerald);
  border: 1px solid rgba(0, 245, 160, 0.3);
}

.impact-badge.moderate {
  background: rgba(255, 180, 0, 0.15);
  color: #ffb400;
  border: 1px solid rgba(255, 180, 0, 0.3);
}

.impact-badge.degraded {
  background: rgba(243, 85, 160, 0.15);
  color: var(--crystal-magenta);
  border: 1px solid rgba(243, 85, 160, 0.3);
}

.scenario-state-text {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 12px;
}

.scenario-detail-bar {
  height: 6px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 3px;
  overflow: hidden;
}

.scenario-fill {
  height: 100%;
  width: 90%;
  background: linear-gradient(90deg, #00f2fe, #9b72ff);
  border-radius: 3px;
  transition: width 0.3s ease, background 0.3s ease;
}

/* ==========================================================================
   测试记录方法指引卡片
   ========================================================================== */
.methodology-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

@media (min-width: 768px) {
  .methodology-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.method-card {
  background: var(--bg-card-solid);
  border: 1px solid var(--crystal-border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.method-card:hover {
  transform: translateY(-3px);
  border-color: var(--crystal-border-hover);
}

.method-number {
  font-size: 2rem;
  font-family: var(--font-mono);
  font-weight: 800;
  background: linear-gradient(135deg, var(--crystal-cyan), var(--crystal-violet));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
  margin-bottom: 16px;
}

.method-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 12px;
}

.method-text {
  font-size: 0.94rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* ==========================================================================
   六篇知识文章卡片网格
   ========================================================================== */
.articles-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

@media (min-width: 768px) {
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1100px) {
  .articles-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.article-card {
  background: var(--bg-card-solid);
  border: 1px solid var(--crystal-border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: var(--crystal-border-hover);
  box-shadow: 0 12px 30px -10px rgba(0, 242, 254, 0.2);
}

.article-meta-row {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 14px;
}

.article-card-title {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.45;
  color: #ffffff;
  margin-bottom: 14px;
}

.article-card-title a {
  color: inherit;
}

.article-card-title a:hover {
  color: var(--crystal-cyan);
}

.article-card-desc {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 20px;
}

.article-card-footer {
  padding-top: 16px;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.read-more-link {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--crystal-cyan);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.read-more-link:hover {
  color: #ffffff;
  transform: translateX(3px);
}

/* ==========================================================================
   套餐说明与选购卡片 (Plans Section)
   ========================================================================== */
.plans-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  align-items: stretch;
}

@media (min-width: 900px) {
  .plans-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.plan-card {
  background: var(--bg-card-solid);
  border: 1px solid var(--crystal-border);
  border-radius: var(--radius-xl);
  padding: 32px 26px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.plan-card.popular {
  border-color: rgba(0, 242, 254, 0.5);
  box-shadow: 0 10px 40px -10px rgba(0, 242, 254, 0.25);
}

.plan-badge-top {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, #00f2fe, #9b72ff);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: 999px;
  letter-spacing: 0.5px;
  white-space: nowrap;
}

.plan-name {
  font-size: 1.35rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 6px;
}

.plan-suitable {
  font-size: 0.85rem;
  color: var(--text-muted);
  min-height: 40px;
  margin-bottom: 20px;
}

.plan-price-wrap {
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.plan-price-main {
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.currency-symbol {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--crystal-cyan);
}

.price-number {
  font-size: 3rem;
  font-family: var(--font-mono);
  font-weight: 800;
  color: #ffffff;
  line-height: 1;
}

.price-cycle {
  font-size: 0.95rem;
  color: var(--text-muted);
}

.plan-average-sub {
  font-size: 0.82rem;
  color: var(--crystal-cyan);
  margin-top: 6px;
  font-family: var(--font-mono);
}

.plan-specs {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 24px;
}

.spec-item {
  display: flex;
  justify-content: space-between;
  font-size: 0.92rem;
  padding: 8px 12px;
  background: rgba(255, 255, 255, 0.03);
  border-radius: var(--radius-sm);
}

.spec-label {
  color: var(--text-muted);
}

.spec-val {
  font-weight: 600;
  color: #ffffff;
}

.plan-features-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 30px;
}

.plan-feature-item {
  font-size: 0.88rem;
  color: var(--text-secondary);
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.check-icon {
  color: var(--crystal-cyan);
  font-weight: 700;
}

/* ==========================================================================
   真实空态评价区 (Authentic Empty State Reviews)
   ========================================================================== */
.empty-reviews-card {
  background: var(--bg-card-solid);
  border: 1px dashed var(--crystal-border);
  border-radius: var(--radius-xl);
  padding: 48px 30px;
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.empty-icon {
  font-size: 2.5rem;
  color: var(--crystal-violet);
  margin-bottom: 16px;
}

.empty-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 10px;
}

.empty-desc {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 580px;
  margin: 0 auto 24px auto;
}

.empty-note {
  display: inline-block;
  padding: 8px 16px;
  background: rgba(255, 255, 255, 0.04);
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ==========================================================================
   手风琴 FAQ
   ========================================================================== */
.faq-accordion {
  display: flex;
  flex-direction: column;
  gap: 14px;
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-card-solid);
  border: 1px solid var(--crystal-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-item.open {
  border-color: rgba(0, 242, 254, 0.4);
}

.faq-question {
  width: 100%;
  padding: 18px 22px;
  background: transparent;
  border: none;
  color: #ffffff;
  font-size: 1.05rem;
  font-weight: 600;
  text-align: left;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  cursor: pointer;
  min-height: var(--touch-target);
}

.faq-icon {
  font-size: 1.4rem;
  font-family: var(--font-mono);
  color: var(--crystal-cyan);
  transition: transform 0.25s ease;
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
  padding: 0 22px;
}

.faq-item.open .faq-answer {
  max-height: 500px;
  transition: max-height 0.3s ease-in-out;
  padding: 0 22px 20px 22px;
}

.faq-answer p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ==========================================================================
   文章详情页独立实色阅读区 (Solid Readable Article Area)
   ========================================================================== */
.article-header-section {
  padding: 50px 0 35px 0;
  text-align: center;
}

.article-title-main {
  font-size: 2.1rem;
  font-weight: 800;
  line-height: 1.35;
  color: #ffffff;
  margin: 16px 0;
}

@media (min-width: 768px) {
  .article-title-main {
    font-size: 2.75rem;
  }
}

.article-meta-bar {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.article-body-wrapper {
  max-width: 860px;
  margin: 0 auto;
  padding-bottom: 80px;
}

/* 核心实色阅读卡片，确保极端高可读性 */
.article-reading-container {
  background-color: var(--bg-card-solid);
  border: 1px solid var(--crystal-border);
  border-radius: var(--radius-xl);
  padding: 40px 32px;
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
}

@media (max-width: 640px) {
  .article-reading-container {
    padding: 26px 18px;
    border-radius: var(--radius-lg);
  }
}

.article-reading-container p {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 22px;
}

.article-reading-container h2 {
  font-size: 1.55rem;
  font-weight: 700;
  color: #ffffff;
  margin: 40px 0 18px 0;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.article-reading-container h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 28px 0 14px 0;
}

/* Markdown 元素美化 */
.crystal-quote {
  background: rgba(0, 242, 254, 0.05);
  border-left: 4px solid var(--crystal-cyan);
  padding: 18px 20px;
  margin: 24px 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.crystal-quote p {
  margin-bottom: 0 !important;
  color: var(--text-secondary);
  font-size: 0.96rem;
}

.crystal-list {
  padding-left: 24px;
  margin-bottom: 24px;
}

.crystal-list li {
  font-size: 1.02rem;
  color: var(--text-secondary);
  margin-bottom: 10px;
  line-height: 1.7;
}

.inline-code {
  font-family: var(--font-mono);
  background: rgba(255, 255, 255, 0.08);
  color: var(--crystal-cyan);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
}

.crystal-hr {
  border: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--crystal-border), transparent);
  margin: 36px 0;
}

/* 响应式数据表格 */
.table-responsive {
  width: 100%;
  overflow-x: auto;
  margin: 28px 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--crystal-border);
}

.crystal-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.92rem;
}

.crystal-table th {
  background: rgba(255, 255, 255, 0.05);
  padding: 14px 16px;
  color: #ffffff;
  font-weight: 600;
  border-bottom: 1px solid var(--crystal-border);
  white-space: nowrap;
}

.crystal-table td {
  padding: 14px 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  color: var(--text-secondary);
  line-height: 1.6;
}

.crystal-table tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

.content-link {
  color: var(--crystal-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.content-link:hover {
  color: #ffffff;
}

/* 公式展示块 */
.formula-block {
  background: rgba(0, 0, 0, 0.35);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-sm);
  padding: 14px 20px;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  color: var(--crystal-cyan);
  margin: 20px 0;
  text-align: center;
}

.formula {
  font-family: var(--font-mono);
  color: var(--crystal-cyan);
  padding: 0 4px;
}

/* 文章底部相关文章推荐 */
.article-related-box {
  margin-top: 50px;
  padding-top: 35px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.related-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 20px;
}

.related-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

@media (min-width: 640px) {
  .related-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.related-card {
  background: var(--bg-card-alt);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-md);
  padding: 18px;
  transition: all 0.2s ease;
}

.related-card:hover {
  border-color: var(--crystal-cyan);
  transform: translateY(-2px);
}

.related-card-title {
  font-size: 1rem;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 6px;
}

.related-card-desc {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ==========================================================================
   全局页脚 Footer
   ========================================================================== */
.site-footer {
  background: #04070d;
  border-top: 1px solid var(--crystal-border);
  padding: 60px 0 35px 0;
  margin-top: 60px;
  position: relative;
  z-index: 10;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
  margin-bottom: 40px;
}

@media (min-width: 768px) {
  .footer-grid {
    grid-template-columns: 1.5fr repeat(3, 1fr);
  }
}

.brand-col .footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
}

.brand-col .brand-name {
  font-size: 1.35rem;
  font-weight: 700;
  color: #ffffff;
}

.theme-tag {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  padding: 2px 8px;
  border-radius: 4px;
  background: rgba(0, 242, 254, 0.1);
  color: var(--crystal-cyan);
  border: 1px solid rgba(0, 242, 254, 0.2);
}

.footer-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 16px;
}

.footer-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8rem;
  color: var(--crystal-emerald);
  background: rgba(0, 245, 160, 0.08);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(0, 245, 160, 0.2);
}

.footer-heading {
  font-size: 1rem;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 18px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.footer-links a:hover {
  color: var(--crystal-cyan);
}

.footer-text-muted {
  font-size: 0.84rem;
  color: var(--text-muted);
}

.footer-disclaimer-box {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  margin-bottom: 30px;
}

.disclaimer-text {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.65;
}

.disclaimer-text strong {
  color: var(--text-secondary);
}

.footer-bottom {
  display: flex;
  flex-direction: column;
  gap: 10px;
  align-items: center;
  text-align: center;
  padding-top: 25px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  font-size: 0.82rem;
  color: var(--text-muted);
}

@media (min-width: 640px) {
  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
  }
}

/* ==========================================================================
   移动端与无障碍硬性增强 (Accessibility & Mobile Optimization)
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .crystal-logo-mark, .btn-crystal-primary {
    transform: none !important;
    box-shadow: none !important;
  }
}

/* 保证手机端无横向滚动条 */
@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }
  .hero-title {
    font-size: 1.95rem;
  }
  .price-number {
    font-size: 2.6rem;
  }
  .article-title-main {
    font-size: 1.75rem;
  }
}