/* ==========================================================================
   GLADOS - 实验室冷光 + 科技严谨 + 精密仪器 (Laboratory Precision Theme)
   ========================================================================== */

:root {
  /* 配色规范 */
  --bg-gradient-start: #0A0E1A; /* 实验室深蓝黑 */
  --bg-gradient-end: #141928;
  --bg-panel: rgba(14, 20, 36, 0.75);
  --bg-panel-solid: #0d1322;
  --bg-card: rgba(16, 23, 42, 0.7);
  --bg-card-subtle: rgba(20, 30, 52, 0.6);

  --primary-cyan: #06B6D4;      /* 仪器青 */
  --secondary-white: #E2E8F0;   /* 冷光白 */
  --text-main: #E2E8F0;
  --text-dim: rgba(226, 232, 240, 0.65); /* 对比度提升至 5.8:1，完全达到 WCAG AA 4.5:1 要求 */
  --border-cyan: rgba(6, 182, 212, 0.3);
  --border-cyan-hover: rgba(6, 182, 212, 0.8);
  --border-subtle: rgba(226, 232, 240, 0.1);

  --cyan-glow: 0 0 18px rgba(6, 182, 212, 0.45);
  --cyan-glow-intense: 0 0 28px rgba(6, 182, 212, 0.8);
  --white-glow: 0 0 12px rgba(226, 232, 240, 0.7);

  --font-mono: 'JetBrains Mono', 'Courier New', monospace;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Source Han Sans CN", sans-serif;

  --radius-sm: 4px;
  --radius-md: 6px;
  --transition: all 0.22s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

/* 锚点滚动距离页眉保护（防止固定 sticky 页眉遮挡标题） */
[id] {
  scroll-margin-top: 80px;
}

/* 无障碍：键盘跳过链接（默认隐藏在视口外，Tab 聚焦时滑入显示） */
.skip-link {
  position: fixed;
  top: -120px;
  left: 20px;
  background: var(--bg-panel-solid);
  color: var(--primary-cyan);
  border: 1px solid var(--primary-cyan);
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  z-index: 99999;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  box-shadow: var(--cyan-glow);
  transition: top 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.skip-link:focus,
.skip-link:focus-visible {
  top: 15px;
  outline: 2px solid var(--secondary-white);
  outline-offset: 2px;
}

/* 无障碍：全局键盘焦点轮廓 */
a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--primary-cyan);
  outline-offset: 3px;
  box-shadow: 0 0 12px rgba(6, 182, 212, 0.6);
}

/* 公用青色文字链接类 */
.link-cyan {
  color: var(--primary-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}
.link-cyan:hover {
  color: var(--secondary-white);
  text-shadow: 0 0 8px var(--primary-cyan);
}

/* 面包屑导航样式 (SEO与用户引导) */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-dim);
  margin-bottom: 24px;
}
.breadcrumb a {
  color: var(--text-dim);
  text-decoration: none;
  transition: var(--transition);
}
.breadcrumb a:hover {
  color: var(--primary-cyan);
  text-shadow: 0 0 8px var(--primary-cyan);
}
.breadcrumb .current {
  color: var(--secondary-white);
}
.breadcrumb .sep {
  color: rgba(6, 182, 212, 0.4);
}

/* 套餐技术规格对比表格（表格语义化支持） */
.pricing-table-wrapper {
  margin-top: 48px;
  background: var(--bg-panel);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-md);
  padding: 24px;
  overflow-x: auto;
  box-shadow: inset 0 0 20px rgba(6, 182, 212, 0.05);
}

.pricing-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  text-align: left;
  min-width: 640px;
}

.pricing-table caption {
  caption-side: top;
  text-align: left;
  font-size: 1rem;
  font-weight: 700;
  color: var(--secondary-white);
  margin-bottom: 16px;
  letter-spacing: 0.5px;
}

.pricing-table th,
.pricing-table td {
  padding: 12px 16px;
  border-bottom: 1px solid rgba(6, 182, 212, 0.15);
  color: var(--text-dim);
}

.pricing-table thead th {
  background: rgba(6, 182, 212, 0.08);
  color: var(--primary-cyan);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
}

.pricing-table tbody th {
  color: var(--secondary-white);
  font-weight: 600;
}

.pricing-table tbody tr:hover {
  background: rgba(6, 182, 212, 0.04);
}

.pricing-table .text-cyan {
  color: var(--primary-cyan);
  font-weight: 600;
}

body {
  font-family: var(--font-body);
  background: linear-gradient(180deg, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 100%);
  background-attachment: fixed;
  color: var(--text-main);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}

/* ==========================================================================
   全屏实验室背景动效：细密网格 + 8秒扫描线 + 3个HUD读数
   ========================================================================== */

/* 细密网格线 (40px 间距，带 radial mask) */
.lab-grid-bg {
  position: fixed;
  inset: 0;
  background-size: 40px 40px;
  background-image:
    linear-gradient(to right, rgba(6, 182, 212, 0.07) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(6, 182, 212, 0.07) 1px, transparent 1px);
  mask-image: radial-gradient(ellipse 90% 85% at 50% 50%, #000 35%, transparent 85%);
  -webkit-mask-image: radial-gradient(ellipse 90% 85% at 50% 50%, #000 35%, transparent 85%);
  pointer-events: none;
  z-index: 0;
}

/* 1 条横向青色扫描线（8 秒周期） */
.lab-scanline {
  position: fixed;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent 0%, rgba(6, 182, 212, 0.2) 20%, #06B6D4 50%, rgba(6, 182, 212, 0.2) 80%, transparent 100%);
  box-shadow: 0 0 12px #06B6D4, 0 0 24px rgba(6, 182, 212, 0.6);
  pointer-events: none;
  z-index: 2;
  animation: labScan 8s linear infinite;
}

@keyframes labScan {
  0% {
    top: 0%;
    opacity: 0;
  }
  3% {
    opacity: 0.9;
  }
  97% {
    opacity: 0.9;
  }
  100% {
    top: 100%;
    opacity: 0;
  }
}

/* 3 个等宽字体实验室读数，固定在屏幕角落，透明度 0.3 */
.hud-corner {
  position: fixed;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  line-height: 1.5;
  color: var(--primary-cyan);
  opacity: 0.3;
  letter-spacing: 0.8px;
  pointer-events: none;
  z-index: 90;
  text-transform: uppercase;
  user-select: none;
}

.hud-tl {
  top: 84px;
  left: 24px;
}

.hud-tr {
  top: 84px;
  right: 24px;
  text-align: right;
}

.hud-br {
  bottom: 20px;
  right: 24px;
  text-align: right;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 10;
}

/* ==========================================================================
   Header & Nav
   ========================================================================== */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 14, 26, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-cyan);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: 1.5px;
  color: var(--secondary-white);
  text-shadow: 0 0 10px rgba(6, 182, 212, 0.5);
}

.logo-badge {
  background: rgba(6, 182, 212, 0.12);
  color: var(--primary-cyan);
  border: 1px solid var(--primary-cyan);
  padding: 1px 7px;
  border-radius: var(--radius-sm);
  font-size: 0.7rem;
  font-weight: 700;
  font-family: var(--font-mono);
  box-shadow: var(--cyan-glow);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-links a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
  font-family: var(--font-mono);
  letter-spacing: 0.5px;
  transition: var(--transition);
  position: relative;
  padding: 6px 0;
}

.nav-links a:hover {
  color: var(--primary-cyan);
  text-shadow: 0 0 8px var(--primary-cyan);
}

.nav-cta {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* ==========================================================================
   CTA 按钮规范：青色描边（无填充），hover时填充青色+文字变深，圆角4px，等宽字体
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  min-height: 48px;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.92rem;
  font-weight: 600;
  letter-spacing: 0.8px;
  text-decoration: none;
  transition: var(--transition);
  cursor: pointer;
  white-space: nowrap;
  box-sizing: border-box;
}

/* 核心 CTA：青色描边按钮（无填充），hover 时填充青色 + 文字变深（#0A0E1A） */
.btn-primary {
  background: transparent;
  border: 1px solid var(--primary-cyan);
  color: var(--primary-cyan);
  box-shadow: 0 0 10px rgba(6, 182, 212, 0.18);
}

.btn-primary:hover {
  background: var(--primary-cyan);
  color: #0A0E1A;
  box-shadow: var(--cyan-glow-intense);
  transform: translateY(-2px);
}

.btn-secondary {
  background: rgba(226, 232, 240, 0.03);
  border: 1px solid rgba(226, 232, 240, 0.22);
  color: var(--secondary-white);
}

.btn-secondary:hover {
  border-color: var(--primary-cyan);
  color: var(--primary-cyan);
  background: rgba(6, 182, 212, 0.06);
  box-shadow: 0 0 12px rgba(6, 182, 212, 0.2);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 7px 16px;
  min-height: 38px;
  font-size: 0.84rem;
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   Hero Section（主视觉区）
   左侧：H1 GLADOS (JetBrains Mono, 双层发光) + 简介 + 按钮 + 指标
   右侧：340×340px 实验室仪器面板 + 200px 三层同心圆刻度盘 + 摆动指针 + 呼吸光点 + 负载条 + 4角读数
   ========================================================================== */
.hero {
  padding: 70px 0 60px 0;
  position: relative;
}

.hero-layout {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

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

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(6, 182, 212, 0.08);
  border: 1px solid var(--border-cyan);
  padding: 5px 14px;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--primary-cyan);
  margin-bottom: 22px;
  letter-spacing: 0.5px;
}

.hero-pill .dot {
  width: 7px;
  height: 7px;
  background-color: var(--primary-cyan);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--primary-cyan);
  animation: pulseGlow 2s ease-in-out infinite;
}

/* H1「GLADOS」使用 JetBrains Mono，700字重，带冷光白 + 仪器青双层发光阴影 */
.hero-h1-glados {
  font-family: var(--font-mono);
  font-size: 3.6rem;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 2px;
  color: var(--secondary-white);
  text-shadow:
    0 0 10px rgba(226, 232, 240, 0.9),
    0 0 25px #06B6D4,
    0 0 50px rgba(6, 182, 212, 0.5);
  margin-bottom: 12px;
  text-transform: uppercase;
}

.hero-subtitle-sub {
  font-family: var(--font-body);
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--primary-cyan);
  letter-spacing: 0.5px;
  margin-bottom: 20px;
}

.hero-description {
  font-size: 1.02rem;
  color: var(--text-dim);
  line-height: 1.75;
  margin-bottom: 32px;
  max-width: 620px;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 36px;
  flex-wrap: wrap;
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-sm);
  padding: 18px 22px;
  box-shadow: inset 0 0 14px rgba(6, 182, 212, 0.08);
}

.metric-item {
  text-align: left;
}

.metric-number {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--secondary-white);
  letter-spacing: 0.5px;
  text-shadow: 0 0 8px rgba(226, 232, 240, 0.4);
}

.metric-label {
  font-size: 0.8rem;
  font-family: var(--font-mono);
  color: var(--text-dim);
  margin-top: 3px;
  letter-spacing: 0.5px;
}

/* ==========================================================================
   右侧 340×340px 实验室仪器面板
   ========================================================================== */
.hero-right {
  display: flex;
  justify-content: center;
  align-items: center;
}

.lab-instrument-panel {
  width: 340px;
  height: 340px;
  background: rgba(10, 14, 26, 0.85);
  border: 1px solid var(--primary-cyan);
  border-radius: var(--radius-sm);
  position: relative;
  box-shadow:
    inset 0 0 24px rgba(6, 182, 212, 0.15),
    0 0 20px rgba(6, 182, 212, 0.25);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  user-select: none;
}

/* 4 个十字角标记 (+) */
.corner-cross {
  position: absolute;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--primary-cyan);
  line-height: 1;
  pointer-events: none;
  opacity: 0.85;
}

.corner-cross.tl { top: 6px; left: 8px; }
.corner-cross.tr { top: 6px; right: 8px; }
.corner-cross.bl { bottom: 6px; left: 8px; }
.corner-cross.br { bottom: 6px; right: 8px; }

/* 4 个角落叠加等宽字体读数 */
.panel-hud-tag {
  position: absolute;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.8px;
  color: rgba(6, 182, 212, 0.7);
  pointer-events: none;
}

.tag-ch01 { top: 18px; left: 16px; }
.tag-ch30 { top: 18px; right: 16px; }
.tag-scanok { bottom: 22px; left: 16px; color: #10B981; }
.tag-live {
  bottom: 22px;
  right: 16px;
  display: flex;
  align-items: center;
  gap: 5px;
  color: var(--primary-cyan);
}
.tag-live::before {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  background: var(--primary-cyan);
  border-radius: 50%;
  box-shadow: 0 0 6px var(--primary-cyan);
  animation: pulseGlow 1.5s infinite;
}

/* 200×200px 精密刻度盘容器 */
.dial-container {
  width: 200px;
  height: 200px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* 3 层同心圆环 */

/* 1. 外层青色实线 + 8 个刻度 */
.ring-outer {
  position: absolute;
  width: 196px;
  height: 196px;
  border: 1.5px solid var(--primary-cyan);
  border-radius: 50%;
  box-shadow: 0 0 10px rgba(6, 182, 212, 0.35);
  animation: rotateClockwise 28s linear infinite;
}

.dial-ticks {
  position: absolute;
  inset: 0;
}

.dial-tick {
  position: absolute;
  top: 0;
  left: 50%;
  width: 1.5px;
  height: 8px;
  background: var(--primary-cyan);
  transform-origin: 50% 98px;
}
.dial-tick:nth-child(1) { transform: rotate(0deg); }
.dial-tick:nth-child(2) { transform: rotate(45deg); }
.dial-tick:nth-child(3) { transform: rotate(90deg); }
.dial-tick:nth-child(4) { transform: rotate(135deg); }
.dial-tick:nth-child(5) { transform: rotate(180deg); }
.dial-tick:nth-child(6) { transform: rotate(225deg); }
.dial-tick:nth-child(7) { transform: rotate(270deg); }
.dial-tick:nth-child(8) { transform: rotate(315deg); }

/* 2. 中层虚线 (反向旋转) */
.ring-middle {
  position: absolute;
  width: 144px;
  height: 144px;
  border: 1.5px dashed rgba(6, 182, 212, 0.6);
  border-radius: 50%;
  animation: rotateCounter 18s linear infinite;
}

/* 3. 内层实线 (正向旋转) */
.ring-inner {
  position: absolute;
  width: 96px;
  height: 96px;
  border: 1px solid rgba(226, 232, 240, 0.4);
  border-radius: 50%;
  animation: rotateClockwise 12s linear infinite;
}

@keyframes rotateClockwise {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes rotateCounter {
  from { transform: rotate(360deg); }
  to { transform: rotate(0deg); }
}

/* 刻度盘中心：1根 80px 白色指针，左右摆动 (±60°，6秒一周期，模拟仪器测量) */
.needle-assembly {
  position: absolute;
  width: 2px;
  height: 160px; /* 双倍高度以中心为 pivot */
  top: 20px;
  left: 99px;
  pointer-events: none;
  animation: needleSwing 6s ease-in-out infinite;
  transform-origin: 50% 50%;
  z-index: 10;
}

.needle-pointer {
  width: 2px;
  height: 80px;
  background: linear-gradient(to top, rgba(226, 232, 240, 0.9), #FFFFFF);
  box-shadow: 0 0 8px #FFFFFF, 0 0 14px rgba(6, 182, 212, 0.8);
  border-radius: 1px 1px 0 0;
}

@keyframes needleSwing {
  0% { transform: rotate(-60deg); }
  50% { transform: rotate(60deg); }
  100% { transform: rotate(-60deg); }
}

/* 指针中心：30px 青色径向渐变光点 (脉冲呼吸 2 秒一周期) */
.needle-center-glow {
  position: absolute;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: radial-gradient(circle, #06B6D4 0%, rgba(6, 182, 212, 0.4) 60%, transparent 100%);
  top: 85px;
  left: 85px;
  pointer-events: none;
  z-index: 12;
  animation: pulseGlow 2s ease-in-out infinite;
}

@keyframes pulseGlow {
  0%, 100% {
    transform: scale(0.92);
    opacity: 0.75;
    box-shadow: 0 0 8px #06B6D4;
  }
  50% {
    transform: scale(1.15);
    opacity: 1;
    box-shadow: 0 0 20px #06B6D4, 0 0 35px rgba(6, 182, 212, 0.5);
  }
}

/* 面板底部：1条 60×4px 青色负载条 (流动 60%→90%) */
.lab-loadbar-wrapper {
  position: absolute;
  bottom: 24px;
  width: 60px;
  height: 4px;
  background: rgba(6, 182, 212, 0.18);
  border: 1px solid rgba(6, 182, 212, 0.5);
  border-radius: 2px;
  overflow: hidden;
}

.lab-loadbar-fill {
  height: 100%;
  background: var(--primary-cyan);
  box-shadow: 0 0 8px var(--primary-cyan);
  animation: loadFlow 3.5s ease-in-out infinite alternate;
}

@keyframes loadFlow {
  0% { width: 60%; }
  100% { width: 90%; }
}

/* ==========================================================================
   Section Common Styling
   ========================================================================== */
section {
  padding: 85px 0;
  position: relative;
  z-index: 10;
}

.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 52px auto;
}

.tag-label {
  display: inline-block;
  padding: 3px 12px;
  border-radius: var(--radius-sm);
  background: rgba(6, 182, 212, 0.08);
  color: var(--primary-cyan);
  border: 1px solid var(--border-cyan);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  margin-bottom: 14px;
  letter-spacing: 1px;
}

.section-title {
  font-size: 2.15rem;
  font-weight: 700;
  letter-spacing: -0.3px;
  margin-bottom: 14px;
  color: var(--secondary-white);
  line-height: 1.3;
}

.section-desc {
  font-size: 1.02rem;
  color: var(--text-dim);
  line-height: 1.65;
}

/* ==========================================================================
   Core Advantages (3 Cards)
   ========================================================================== */
.core-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.adv-card {
  background: var(--bg-card);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-sm);
  padding: 34px 26px;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  position: relative;
}

.adv-card:hover {
  transform: translateY(-4px);
  border-color: var(--primary-cyan);
  box-shadow: 0 8px 26px rgba(0, 0, 0, 0.4), var(--cyan-glow);
}

.adv-icon-box {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-sm);
  background: rgba(6, 182, 212, 0.09);
  border: 1px solid var(--border-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--primary-cyan);
}

.adv-icon-box svg {
  width: 26px;
  height: 26px;
}

.adv-title {
  font-size: 1.22rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--secondary-white);
  font-family: var(--font-mono);
  letter-spacing: 0.5px;
}

.adv-desc {
  font-size: 0.94rem;
  color: var(--text-dim);
  line-height: 1.6;
  margin-bottom: 20px;
}

.adv-bullets {
  margin-top: auto;
  list-style: none;
  border-top: 1px solid var(--border-subtle);
  padding-top: 16px;
}

.adv-bullets li {
  font-size: 0.88rem;
  color: rgba(226, 232, 240, 0.8);
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}

.adv-bullets li svg {
  width: 14px;
  height: 14px;
  color: var(--primary-cyan);
  flex-shrink: 0;
}

/* ==========================================================================
   Streaming & AI Support
   ========================================================================== */
.unlock-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 26px;
}

.unlock-category {
  background: var(--bg-card);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-sm);
  padding: 32px;
}

.unlock-head {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 14px;
}

.unlock-badge {
  background: rgba(6, 182, 212, 0.12);
  color: var(--primary-cyan);
  border: 1px solid var(--border-cyan);
  font-size: 0.76rem;
  font-weight: 700;
  font-family: var(--font-mono);
  padding: 3px 9px;
  border-radius: var(--radius-sm);
  letter-spacing: 0.5px;
}

.unlock-category-title {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--secondary-white);
  font-family: var(--font-mono);
}

.unlock-category-desc {
  font-size: 0.94rem;
  color: var(--text-dim);
  margin-bottom: 22px;
}

.chips-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.chip-item {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--bg-card-subtle);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--secondary-white);
}

.chip-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--primary-cyan);
  box-shadow: 0 0 6px var(--primary-cyan);
}

/* ==========================================================================
   Pricing Table (GlaDos 真实套餐价格)
   ========================================================================== */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  align-items: stretch;
}

.price-card {
  background: var(--bg-card);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-sm);
  padding: 36px 26px;
  position: relative;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}

.price-card:hover {
  transform: translateY(-4px);
  border-color: var(--primary-cyan);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4), 0 0 16px rgba(6, 182, 212, 0.25);
}

.price-card.featured {
  border-color: var(--primary-cyan);
  background: linear-gradient(180deg, rgba(16, 26, 48, 0.85) 0%, rgba(10, 16, 30, 0.85) 100%);
  box-shadow: 0 0 24px rgba(6, 182, 212, 0.25), inset 0 0 16px rgba(6, 182, 212, 0.08);
}

.popular-badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: #0A0E1A;
  color: var(--primary-cyan);
  border: 1px solid var(--primary-cyan);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 700;
  padding: 3px 12px;
  border-radius: var(--radius-sm);
  letter-spacing: 0.8px;
  box-shadow: var(--cyan-glow);
}

.price-plan {
  font-size: 1.25rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--secondary-white);
  margin-bottom: 6px;
}

.price-desc {
  font-size: 0.88rem;
  color: var(--text-dim);
  margin-bottom: 20px;
  min-height: 42px;
}

.price-val {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-bottom: 22px;
}

.currency {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary-cyan);
  font-family: var(--font-mono);
}

.amount {
  font-size: 2.6rem;
  font-weight: 800;
  color: var(--secondary-white);
  font-family: var(--font-mono);
  letter-spacing: -1px;
}

.period {
  font-size: 0.85rem;
  color: var(--text-dim);
  font-family: var(--font-mono);
}

.price-features {
  list-style: none;
  margin: 24px 0;
  flex-grow: 1;
}

.price-features li {
  font-size: 0.88rem;
  color: rgba(226, 232, 240, 0.85);
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.price-features li svg {
  width: 15px;
  height: 15px;
  color: var(--primary-cyan);
  flex-shrink: 0;
}

/* ==========================================================================
   User Reviews
   ========================================================================== */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-sm);
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review-stars {
  color: var(--primary-cyan);
  margin-bottom: 14px;
  display: flex;
  gap: 3px;
}

.review-stars svg {
  width: 15px;
  height: 15px;
  fill: currentColor;
}

.review-text {
  font-size: 0.94rem;
  color: var(--text-main);
  line-height: 1.65;
  margin-bottom: 22px;
  font-style: italic;
}

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

.author-avatar {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background: rgba(6, 182, 212, 0.1);
  border: 1px solid var(--border-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--primary-cyan);
  font-family: var(--font-mono);
}

.author-name {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--secondary-white);
  font-family: var(--font-mono);
}

.author-role {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* FAQ (6 Questions) with pure HTML details/summary */
.faq-list {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

/* Article Embedded FAQ Styling */
.article-faq-wrap {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px dashed rgba(6, 182, 212, 0.3);
}

.article-faq-title {
  font-size: 1.05rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--primary-cyan);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
  letter-spacing: 0.5px;
}

.article-faq-wrap .faq-item {
  margin-bottom: 12px;
  background: rgba(10, 14, 26, 0.65);
  border: 1px solid rgba(6, 182, 212, 0.25);
}

.article-faq-wrap .faq-item summary {
  padding: 14px 18px;
  font-size: 0.95rem;
  color: var(--secondary-white);
}

.article-faq-wrap .faq-answer {
  padding: 0 18px 16px 18px;
  font-size: 0.9rem;
  line-height: 1.65;
  color: var(--text-dim);
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: var(--transition);
}

.faq-item:hover {
  border-color: var(--primary-cyan);
}

.faq-item summary {
  padding: 20px 24px;
  font-size: 1.02rem;
  font-weight: 600;
  color: var(--secondary-white);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  user-select: none;
  font-family: var(--font-body);
}

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

.faq-icon {
  width: 18px;
  height: 18px;
  color: var(--primary-cyan);
  transition: transform 0.25s ease;
  flex-shrink: 0;
}

.faq-item[open] summary .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 24px 22px 24px;
  font-size: 0.94rem;
  color: var(--text-dim);
  line-height: 1.7;
  border-top: 1px solid var(--border-subtle);
  padding-top: 16px;
}

/* Call to Action Banner */
.cta-banner {
  margin-top: 60px;
  background: rgba(14, 20, 36, 0.9);
  border: 1px solid var(--primary-cyan);
  border-radius: var(--radius-sm);
  padding: 48px 30px;
  text-align: center;
  box-shadow: inset 0 0 20px rgba(6, 182, 212, 0.15), 0 0 24px rgba(6, 182, 212, 0.2);
}

.cta-banner h2 {
  font-size: 2rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--secondary-white);
  margin-bottom: 12px;
}

.cta-banner p {
  color: var(--text-dim);
  max-width: 600px;
  margin: 0 auto 28px auto;
  font-size: 1rem;
}

/* ==========================================================================
   Footer (Strictly 4 titles only)
   ========================================================================== */
footer {
  border-top: 1px solid var(--border-cyan);
  background: #080B14;
  padding: 40px 0;
  margin-top: 80px;
  position: relative;
  z-index: 10;
}

.footer-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 36px;
  list-style: none;
  flex-wrap: wrap;
}

.footer-nav a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
  font-family: var(--font-mono);
  transition: var(--transition);
  padding: 6px 10px;
}

.footer-nav a:hover {
  color: var(--primary-cyan);
  text-shadow: 0 0 8px var(--primary-cyan);
}

.footer-copyright {
  text-align: center;
  color: rgba(226, 232, 240, 0.35);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  margin-top: 24px;
  letter-spacing: 0.5px;
}

/* ==========================================================================
   Inner Pages (About, Terms, Privacy, Sitemap, Guide)
   ========================================================================== */
.inner-page-header {
  padding: 50px 0 30px 0;
  border-bottom: 1px solid var(--border-cyan);
  margin-bottom: 40px;
}

.inner-content {
  max-width: 860px;
  margin: 0 auto 80px auto;
}

.content-block {
  background: var(--bg-card);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-sm);
  padding: 32px;
  margin-bottom: 26px;
}

.content-block h2 {
  font-size: 1.35rem;
  font-weight: 700;
  font-family: var(--font-mono);
  margin-bottom: 14px;
  color: var(--secondary-white);
  display: flex;
  align-items: center;
  gap: 10px;
}

.content-block p {
  font-size: 0.96rem;
  color: rgba(226, 232, 240, 0.85);
  line-height: 1.75;
  margin-bottom: 12px;
}

.content-block p:last-child {
  margin-bottom: 0;
}

.content-block ul, .content-block ol {
  padding-left: 22px;
  color: rgba(226, 232, 240, 0.85);
  line-height: 1.75;
  margin-top: 10px;
}

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

.highlight-box {
  background: rgba(6, 182, 212, 0.08);
  border-left: 3px solid var(--primary-cyan);
  padding: 14px 18px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 18px 0;
  font-size: 0.94rem;
  color: var(--secondary-white);
}

.text-center {
  text-align: center;
}

/* ==========================================================================
   Responsive Media Queries (@media)
   ========================================================================== */
@media (max-width: 992px) {
  .hero-layout {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .hero-right {
    order: -1; /* Place instrument dial gracefully above on mid-screens or below */
    margin: 0 auto;
  }
  .hero-h1-glados {
    font-size: 2.8rem;
  }
  .core-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }
  .pricing-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  .reviews-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }
}

@media (max-width: 768px) {
  .hud-corner {
    display: none; /* Hide background HUD on small touch screens to avoid clutter */
  }
  .nav-links {
    display: none;
  }
  .hero {
    padding: 40px 0 30px 0;
  }
  .hero-h1-glados {
    font-size: 2.3rem;
    letter-spacing: 1px;
  }
  .hero-subtitle-sub {
    font-size: 1.15rem;
  }
  .hero-description {
    font-size: 0.95rem;
  }
  .hero-actions {
    flex-direction: column;
    width: 100%;
  }
  .hero-actions .btn {
    width: 100%;
  }
  .hero-metrics {
    grid-template-columns: 1fr;
    gap: 14px;
    padding: 18px;
  }
  .lab-instrument-panel {
    transform: scale(0.9);
    max-width: 100%;
  }
  .btn-sm {
    min-height: 44px;
    padding: 10px 18px;
    font-size: 0.88rem;
  }
  .unlock-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }
  .chips-grid {
    grid-template-columns: 1fr;
  }
  .section-title {
    font-size: 1.7rem;
  }
  .cta-banner {
    padding: 32px 18px;
  }
  .cta-banner h2 {
    font-size: 1.5rem;
  }
  .footer-nav {
    flex-direction: column;
    gap: 14px;
  }
}

/* 窄屏手机适配（360px ~ 390px 极限视口） */
@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }
  .lab-instrument-panel {
    transform: scale(0.82);
    margin: -15px auto;
  }
}

/* 无障碍支持：运动减弱模式（遵循 prefers-reduced-motion） */
@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;
  }
  .lab-scanline,
  .hud-corner {
    display: none !important;
  }
}