/* ==========================================================================
   深蓝太空背景 + 星云粒子动效 + 发光火箭穿越屏幕 + HUD 界面元素点缀
   COSMIC HUD SPACE DESIGN SYSTEM
   ========================================================================== */

:root {
  --space-dark: #020817;
  --space-deep: #051330;
  --space-card: rgba(6, 22, 54, 0.78);
  --hud-cyan: #00f0ff;
  --hud-blue: #0ea5e9;
  --hud-glow: rgba(0, 240, 255, 0.5);
  --hud-flare: #ff8800;
  --hud-border: rgba(0, 240, 255, 0.32);
  --hud-border-bright: rgba(0, 240, 255, 0.85);
  --text-main: #f0f8ff;
  --text-dim: #94b8e0;
  --text-muted: #5375a3;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "SF Mono", "Fira Code", Consolas, "Courier New", monospace;
  --trans: all 0.28s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--space-dark);
  color: var(--text-main);
  font-family: var(--font-sans);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body {
  line-height: 1.65;
  overflow-x: hidden;
  background-color: var(--space-dark);
  position: relative;
  min-height: 100vh;
}

/* 深蓝太空背景 + 星云粒子动效层 */
.cosmic-nebula-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 0;
  background-image: 
    radial-gradient(circle at 18% 25%, rgba(0, 180, 255, 0.16) 0%, transparent 45%),
    radial-gradient(circle at 82% 75%, rgba(138, 43, 226, 0.18) 0%, transparent 50%),
    radial-gradient(circle at 50% 50%, rgba(14, 165, 233, 0.1) 0%, transparent 60%),
    linear-gradient(rgba(0, 240, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 240, 255, 0.04) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 100% 100%, 48px 48px, 48px 48px;
}

/* 星光闪烁层 */
.cosmic-stars {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 1;
  background: 
    radial-gradient(1px 1px at 15% 15%, #ffffff 100%, transparent),
    radial-gradient(1.5px 1.5px at 35% 65%, #00f0ff 100%, transparent),
    radial-gradient(1px 1px at 60% 20%, #ffffff 100%, transparent),
    radial-gradient(2px 2px at 80% 40%, #00f0ff 100%, transparent),
    radial-gradient(1px 1px at 25% 85%, #ffffff 100%, transparent),
    radial-gradient(1.5px 1.5px at 75% 85%, #7dd3fc 100%, transparent),
    radial-gradient(1px 1px at 90% 10%, #ffffff 100%, transparent);
  background-size: 100% 100%;
  animation: cosmicTwinkle 5s infinite ease-in-out alternate;
}

@keyframes cosmicTwinkle {
  0% { opacity: 0.6; }
  50% { opacity: 1; }
  100% { opacity: 0.7; }
}

/* 发光火箭穿越屏幕动效 (发光火箭 + 粒子尾焰飞跃) */
.space-rocket-flyby {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 2;
  overflow: hidden;
}

.rocket-vessel {
  position: absolute;
  width: 48px;
  height: 48px;
  color: var(--hud-cyan);
  filter: drop-shadow(0 0 16px var(--hud-cyan)) drop-shadow(-15px 15px 22px rgba(255, 136, 0, 0.85));
  opacity: 0;
  animation: rocketTransFlight 12s cubic-bezier(0.25, 1, 0.5, 1) infinite;
}

@keyframes rocketTransFlight {
  0% {
    transform: translate(-100px, 100vh) rotate(-38deg) scale(0.65);
    opacity: 0;
  }
  10% {
    opacity: 0.95;
  }
  30% {
    transform: translate(110vw, -120px) rotate(-38deg) scale(0.95);
    opacity: 1;
  }
  31%, 100% {
    transform: translate(110vw, -120px) rotate(-38deg);
    opacity: 0;
  }
}

.skip {
  position: absolute;
  top: -100px;
  left: 20px;
  background: var(--hud-cyan);
  color: #020817;
  padding: 8px 16px;
  font-weight: 700;
  z-index: 9999;
}
.skip:focus {
  top: 20px;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 3;
}

/* HUD 元素点缀类 (角括号、瞄准十字、坐标读数) */
.hud-frame {
  position: relative;
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  backdrop-filter: blur(14px);
  border-radius: 4px;
  box-shadow: 0 10px 40px rgba(2, 12, 35, 0.7), inset 0 0 15px rgba(0, 240, 255, 0.05);
}
.hud-frame::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  width: 8px;
  height: 8px;
  border-top: 2px solid var(--hud-cyan);
  border-left: 2px solid var(--hud-cyan);
  pointer-events: none;
}
.hud-frame::after {
  content: "";
  position: absolute;
  bottom: -1px;
  right: -1px;
  width: 8px;
  height: 8px;
  border-bottom: 2px solid var(--hud-cyan);
  border-right: 2px solid var(--hud-cyan);
  pointer-events: none;
}

.hud-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--hud-cyan);
  letter-spacing: 1px;
  text-transform: uppercase;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.hud-tag::before {
  content: "◈";
  font-size: 9px;
  color: var(--hud-flare);
}

/* 渐变标题与发光文字 */
.grad-text {
  background: linear-gradient(135deg, #ffffff 10%, #7dd3fc 45%, var(--hud-cyan) 85%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
  text-shadow: 0 0 24px rgba(0, 240, 255, 0.4);
}

.hud-flare-text {
  color: var(--hud-flare);
  text-shadow: 0 0 10px rgba(255, 136, 0, 0.6);
}

/* 按钮设计 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.5px;
  padding: 12px 28px;
  text-decoration: none;
  cursor: pointer;
  transition: var(--trans);
  border-radius: 4px;
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: linear-gradient(135deg, rgba(0, 240, 255, 0.9), rgba(14, 165, 233, 0.95));
  color: #020817;
  border: 1px solid var(--hud-cyan);
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.45);
}
.btn-primary:hover {
  background: linear-gradient(135deg, #38bdf8, var(--hud-cyan));
  color: #01040f;
  box-shadow: 0 0 32px rgba(0, 240, 255, 0.85);
  transform: translateY(-2px);
}

.btn-ghost {
  background: rgba(0, 240, 255, 0.08);
  color: var(--hud-cyan);
  border: 1px solid var(--hud-border);
  backdrop-filter: blur(8px);
}
.btn-ghost:hover {
  background: rgba(0, 240, 255, 0.18);
  border-color: var(--hud-cyan);
  box-shadow: 0 0 18px rgba(0, 240, 255, 0.35);
  transform: translateY(-2px);
}

/* 徽章 */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 14px;
  background: rgba(0, 240, 255, 0.09);
  border: 1px solid var(--hud-border);
  color: var(--hud-cyan);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.5px;
  border-radius: 3px;
  backdrop-filter: blur(8px);
  margin-bottom: 20px;
}
.badge-beacon {
  width: 7px;
  height: 7px;
  background: var(--hud-cyan);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--hud-cyan);
  animation: hudPulse 1.8s infinite ease-in-out;
}
@keyframes hudPulse {
  0%, 100% { opacity: 0.35; transform: scale(0.85); }
  50% { opacity: 1; transform: scale(1.3); }
}

/* ==========================================================================
   1. 顶部导航 site-header
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(2, 8, 23, 0.86);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(0, 240, 255, 0.2);
  box-shadow: 0 4px 25px rgba(0, 180, 255, 0.12);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: #ffffff;
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 17px;
  letter-spacing: 0.5px;
}
.brand-icon-space {
  width: 36px;
  height: 36px;
  background: rgba(0, 240, 255, 0.12);
  border: 1px solid var(--hud-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--hud-cyan);
  box-shadow: 0 0 14px rgba(0, 240, 255, 0.35);
  border-radius: 4px;
}
.site-nav {
  display: flex;
  align-items: center;
  gap: 28px;
}
.site-nav a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 14.5px;
  font-weight: 600;
  transition: var(--trans);
  position: relative;
  padding: 6px 0;
}
.site-nav a:hover,
.site-nav a.is-on {
  color: var(--hud-cyan);
  text-shadow: 0 0 8px rgba(0, 240, 255, 0.6);
}
.site-nav a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--hud-cyan);
  box-shadow: 0 0 8px var(--hud-cyan);
  transition: var(--trans);
}
.site-nav a:hover::after,
.site-nav a.is-on::after {
  width: 100%;
}
.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--hud-border);
  color: var(--hud-cyan);
  padding: 8px 12px;
  cursor: pointer;
  border-radius: 4px;
}
.nav-toggle span, .nav-toggle span::before, .nav-toggle span::after {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--hud-cyan);
  position: relative;
  transition: var(--trans);
}
.nav-toggle span::before {
  content: "";
  position: absolute;
  top: -6px;
}
.nav-toggle span::after {
  content: "";
  position: absolute;
  top: 6px;
}

/* ==========================================================================
   2. Hero 区
   ========================================================================== */
.hero {
  padding: 80px 0 60px;
  position: relative;
  overflow: hidden;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}
.hero-content h1 {
  font-size: 40px;
  line-height: 1.25;
  font-weight: 800;
  margin-bottom: 20px;
}
.hero-content .lead {
  font-size: 16.5px;
  line-height: 1.8;
  color: var(--text-dim);
  margin-bottom: 28px;
}
.sell-points {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px 18px;
  margin-bottom: 32px;
}
.sell-points li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: var(--text-main);
}
.sell-points li svg {
  flex-shrink: 0;
  color: var(--hud-cyan);
  filter: drop-shadow(0 0 6px var(--hud-cyan));
}
.hero-btns {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}
.hero-plat-hint {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 12.5px;
  color: var(--text-muted);
  font-family: var(--font-mono);
}
.hero-plat-hint svg {
  width: 17px;
  height: 17px;
  fill: currentColor;
}

/* 右侧太空 HUD 客户端模拟界面 mock-window */
.hero-visual {
  position: relative;
}
.mock-window-space {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  box-shadow: 0 10px 40px rgba(2, 12, 35, 0.75), inset 0 0 20px rgba(0, 240, 255, 0.08);
  backdrop-filter: blur(14px);
  border-radius: 6px;
  overflow: hidden;
  position: relative;
}
.mock-window-space::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 10px;
  height: 10px;
  border-top: 2px solid var(--hud-cyan);
  border-left: 2px solid var(--hud-cyan);
}
.mock-window-space::after {
  content: "";
  position: absolute;
  bottom: 0;
  right: 0;
  width: 10px;
  height: 10px;
  border-bottom: 2px solid var(--hud-cyan);
  border-right: 2px solid var(--hud-cyan);
}

.mock-window-header {
  padding: 12px 16px;
  background: rgba(0, 240, 255, 0.08);
  border-bottom: 1px solid var(--hud-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.mock-window-dots {
  display: flex;
  gap: 6px;
}
.mock-window-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}
.dot-red { background: #ff4d6d; }
.dot-yellow { background: #ffaa00; }
.dot-green { background: #00f0ff; }
.mock-window-title {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--hud-cyan);
  letter-spacing: 1px;
}

.mock-window-body {
  padding: 22px;
}
.connection-status-card {
  background: rgba(0, 240, 255, 0.05);
  border: 1px solid rgba(0, 240, 255, 0.2);
  border-radius: 4px;
  padding: 14px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 18px;
}
.status-info {
  display: flex;
  align-items: center;
  gap: 12px;
}
.status-beacon-active {
  width: 12px;
  height: 12px;
  background: var(--hud-cyan);
  border-radius: 50%;
  box-shadow: 0 0 12px var(--hud-cyan);
}

/* 延迟曲线图 (SVG 渐变面积图) */
.waveform-box {
  background: rgba(2, 10, 26, 0.8);
  border: 1px solid rgba(0, 240, 255, 0.18);
  border-radius: 4px;
  padding: 14px;
  margin-bottom: 18px;
}
.waveform-header {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--text-dim);
  margin-bottom: 8px;
}
.waveform-svg {
  width: 100%;
  height: 64px;
  display: block;
}

/* 节点列表 */
.mock-node-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.mock-node-item {
  background: rgba(0, 240, 255, 0.04);
  border: 1px solid rgba(0, 240, 255, 0.15);
  border-radius: 4px;
  padding: 10px 14px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 12.5px;
}
.mock-node-item.active {
  border-color: var(--hud-cyan);
  background: rgba(0, 240, 255, 0.12);
}
.mock-node-item .ping {
  color: var(--hud-cyan);
  font-weight: 700;
}

/* 两个 HUD 浮动卡片 */
.hud-float-card {
  position: absolute;
  background: rgba(6, 26, 64, 0.92);
  border: 1px solid var(--hud-cyan);
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.35);
  backdrop-filter: blur(12px);
  padding: 12px 18px;
  border-radius: 4px;
  font-family: var(--font-mono);
  display: flex;
  flex-direction: column;
  gap: 2px;
  z-index: 5;
  animation: hudFloat 4s ease-in-out infinite;
}
.hfc-top {
  top: -15px;
  right: -20px;
}
.hfc-bot {
  bottom: -15px;
  left: -20px;
  animation-delay: -2s;
}
@keyframes hudFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}
.hud-float-card strong {
  font-size: 22px;
  color: var(--hud-cyan);
  line-height: 1.1;
  text-shadow: 0 0 8px rgba(0, 240, 255, 0.6);
}
.hud-float-card span {
  font-size: 11px;
  color: var(--text-dim);
}

/* ==========================================================================
   3. 平台入口带 platform-strip
   ========================================================================== */
.platform-strip {
  padding: 40px 0;
  border-top: 1px solid rgba(0, 240, 255, 0.15);
  border-bottom: 1px solid rgba(0, 240, 255, 0.15);
  background: rgba(4, 16, 42, 0.5);
}
.platform-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
}
.plat-card {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  padding: 20px 14px;
  border-radius: 4px;
  text-decoration: none;
  color: var(--text-main);
  text-align: center;
  transition: var(--trans);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  backdrop-filter: blur(8px);
}
.plat-card:hover {
  border-color: var(--hud-cyan);
  background: rgba(0, 240, 255, 0.12);
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 240, 255, 0.25);
}
.plat-card svg {
  width: 28px;
  height: 28px;
  fill: var(--hud-cyan);
  filter: drop-shadow(0 0 6px rgba(0, 240, 255, 0.5));
}
.plat-card h3 {
  font-size: 15px;
  color: #ffffff;
}
.plat-card p {
  font-size: 11.5px;
  color: var(--text-dim);
  font-family: var(--font-mono);
}

/* ==========================================================================
   4. 数据速览 stats-band
   ========================================================================== */
.stats-band {
  padding: 50px 0;
  background: linear-gradient(180deg, rgba(2, 8, 23, 0.6) 0%, rgba(5, 22, 54, 0.4) 100%);
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.stat {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  padding: 24px 20px;
  border-radius: 4px;
  text-align: center;
  backdrop-filter: blur(10px);
}
.stat b {
  display: block;
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 800;
  color: var(--hud-cyan);
  text-shadow: 0 0 12px rgba(0, 240, 255, 0.5);
  margin-bottom: 6px;
}
.stat span {
  font-size: 13.5px;
  color: var(--text-dim);
}

/* ==========================================================================
   5. 六大能力 feature-grid
   ========================================================================== */
.section {
  padding: 80px 0;
  position: relative;
}
.section h2 {
  font-size: 32px;
  text-align: center;
  margin-bottom: 12px;
  color: #ffffff;
  font-weight: 800;
  letter-spacing: -0.5px;
}
.section p.sub {
  text-align: center;
  font-size: 15.5px;
  color: var(--text-dim);
  max-width: 680px;
  margin: 0 auto 48px;
}
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.feature {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  padding: 30px 24px;
  border-radius: 6px;
  backdrop-filter: blur(10px);
  transition: var(--trans);
  position: relative;
  overflow: hidden;
}
.feature:hover {
  border-color: var(--hud-cyan);
  transform: translateY(-4px);
  box-shadow: 0 10px 30px rgba(0, 240, 255, 0.2);
}
.feature-icon-box {
  width: 48px;
  height: 48px;
  background: rgba(0, 240, 255, 0.1);
  border: 1px solid var(--hud-border);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  color: var(--hud-cyan);
}
.feature-icon-box svg {
  width: 24px;
  height: 24px;
}
.feature h3 {
  font-size: 18px;
  color: #ffffff;
  margin-bottom: 10px;
}
.feature p {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-dim);
}

/* ==========================================================================
   6. 工作原理 tech-grid
   ========================================================================== */
.tech-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}
.tech-block {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  border-radius: 6px;
  padding: 32px 28px;
  backdrop-filter: blur(12px);
}
.tech-block h3 {
  font-size: 20px;
  color: #ffffff;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.tech-badge-num {
  font-family: var(--font-mono);
  font-size: 13px;
  background: rgba(0, 240, 255, 0.15);
  color: var(--hud-cyan);
  padding: 2px 8px;
  border: 1px solid var(--hud-cyan);
  border-radius: 3px;
}
.tech-step-item {
  display: flex;
  gap: 16px;
  margin-bottom: 20px;
}
.tech-step-item:last-child {
  margin-bottom: 0;
}
.tech-step-item .num {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 800;
  color: var(--hud-cyan);
  opacity: 0.8;
  line-height: 1;
}
.tech-step-item strong {
  font-size: 15px;
  color: #ffffff;
  display: block;
  margin-bottom: 4px;
}
.tech-step-item p {
  font-size: 13.5px;
  color: var(--text-dim);
  line-height: 1.65;
}

/* 扩展插图 */
.news-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 24px;
  margin-top: 36px;
}
.news-card {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  border-radius: 6px;
  overflow: hidden;
  backdrop-filter: blur(10px);
}
.news-card img {
  width: 100%;
  height: 210px;
  object-fit: cover;
  display: block;
}
.news-card > div {
  padding: 22px;
}

/* ==========================================================================
   7. 用户评价 review-grid
   ========================================================================== */
.score-bar {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  border-radius: 4px;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  max-width: 620px;
  margin: 0 auto 36px;
  backdrop-filter: blur(10px);
}
.review-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.review {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  border-radius: 6px;
  padding: 24px;
  backdrop-filter: blur(10px);
  display: flex;
  flex-direction: column;
  transition: var(--trans);
}
.review:hover {
  border-color: var(--hud-cyan);
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 240, 255, 0.2);
}
.review-top {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}
.avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 16px;
  color: #020817;
}
.a1 { background: #00f0ff; }
.a2 { background: #38bdf8; }
.a3 { background: #818cf8; }
.a4 { background: #ffaa00; }
.review-role {
  font-size: 11px;
  color: var(--hud-cyan);
  font-family: var(--font-mono);
}
.review-stars {
  color: #ffaa00;
  margin-bottom: 12px;
  display: flex;
  gap: 3px;
}
.review blockquote {
  font-size: 13.5px;
  color: var(--text-dim);
  line-height: 1.65;
  margin-bottom: 16px;
  font-style: italic;
  flex: 1;
}
.review-foot {
  font-size: 11.5px;
  color: var(--text-muted);
  font-family: var(--font-mono);
  border-top: 1px solid rgba(0, 240, 255, 0.1);
  padding-top: 10px;
}

/* ==========================================================================
   8. 认证背书 trust-grid
   ========================================================================== */
.trust-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.trust-card {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  padding: 24px;
  border-radius: 6px;
  text-align: center;
  backdrop-filter: blur(10px);
}
.trust-card svg {
  width: 36px;
  height: 36px;
  color: var(--hud-cyan);
  margin-bottom: 14px;
  filter: drop-shadow(0 0 8px rgba(0, 240, 255, 0.5));
}
.trust-card h3 {
  font-size: 16px;
  color: #ffffff;
  margin-bottom: 6px;
}
.trust-card p {
  font-size: 12.5px;
  color: var(--text-dim);
  line-height: 1.6;
}

/* ==========================================================================
   9. 对比表 cmp-table
   ========================================================================== */
.cmp-wrapper {
  overflow-x: auto;
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  border-radius: 6px;
  backdrop-filter: blur(14px);
  padding: 4px;
}
.cmp-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 14px;
}
.cmp-table th, .cmp-table td {
  padding: 16px 20px;
  border-bottom: 1px solid rgba(0, 240, 255, 0.12);
}
.cmp-table th {
  background: rgba(0, 240, 255, 0.08);
  color: #ffffff;
  font-weight: 700;
  font-family: var(--font-mono);
}
.cmp-table .hl {
  background: rgba(0, 240, 255, 0.12);
  color: var(--hud-cyan);
  font-weight: 700;
  border-left: 1px solid rgba(0, 240, 255, 0.35);
  border-right: 1px solid rgba(0, 240, 255, 0.35);
}
.cmp-table tr:last-child td {
  border-bottom: none;
}
.cmp-note {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 14px;
  text-align: right;
  font-family: var(--font-mono);
}

/* ==========================================================================
   10. FAQ faq-list
   ========================================================================== */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.faq-item {
  background: var(--space-card);
  border: 1px solid var(--hud-border);
  border-radius: 4px;
  backdrop-filter: blur(10px);
  overflow: hidden;
  transition: var(--trans);
}
.faq-item:hover {
  border-color: var(--hud-cyan);
}
.faq-item button {
  width: 100%;
  background: transparent;
  border: none;
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: #ffffff;
  font-size: 16px;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  font-family: var(--font-sans);
}
.faq-item button span:last-child {
  font-family: var(--font-mono);
  font-size: 20px;
  color: var(--hud-cyan);
  transition: var(--trans);
}
.faq-item .ans {
  display: none;
  padding: 0 24px 20px;
  font-size: 14.5px;
  color: var(--text-dim);
  line-height: 1.8;
  border-top: 1px solid rgba(0, 240, 255, 0.1);
  padding-top: 16px;
}
.faq-item.open .ans {
  display: block;
}
.faq-item.open button span:last-child {
  transform: rotate(45deg);
}

/* ==========================================================================
   11. CTA 横幅 cta-band
   ========================================================================== */
.cta-band {
  padding: 80px 0;
  background: radial-gradient(circle at 50% 50%, rgba(0, 180, 255, 0.22) 0%, rgba(2, 8, 23, 0.85) 70%);
  border-top: 1px solid rgba(0, 240, 255, 0.2);
  border-bottom: 1px solid rgba(0, 240, 255, 0.2);
  text-align: center;
}
.cta-band h2 {
  font-size: 38px;
  color: #ffffff;
  margin-bottom: 16px;
  font-weight: 800;
}
.cta-band p {
  font-size: 16.5px;
  color: var(--text-dim);
  max-width: 620px;
  margin: 0 auto 32px;
}
.cta-btns {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* ==========================================================================
   12. 页脚 site-footer
   ========================================================================== */
.site-footer {
  padding: 60px 0 30px;
  background: #01040f;
  border-top: 1px solid rgba(0, 240, 255, 0.15);
}
.foot-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 36px;
  margin-bottom: 40px;
}
.foot-grid h3 {
  font-size: 15px;
  color: #ffffff;
  margin-bottom: 16px;
  font-family: var(--font-mono);
  letter-spacing: 0.5px;
}
.foot-grid a {
  display: block;
  color: var(--text-dim);
  text-decoration: none;
  font-size: 13.5px;
  margin-bottom: 10px;
  transition: var(--trans);
}
.foot-grid a:hover {
  color: var(--hud-cyan);
  text-shadow: 0 0 6px var(--hud-cyan);
  transform: translateX(3px);
}
.foot-grid p {
  font-size: 13.5px;
  color: var(--text-muted);
  line-height: 1.7;
}
.footer-seo {
  padding: 20px;
  background: rgba(0, 240, 255, 0.03);
  border: 1px solid rgba(0, 240, 255, 0.1);
  border-radius: 4px;
  margin-bottom: 24px;
  font-size: 12px;
  color: var(--text-muted);
  line-height: 1.8;
}
.footer-seo strong {
  color: var(--hud-cyan);
  font-family: var(--font-mono);
}
.copy {
  text-align: center;
  font-size: 12px;
  color: var(--text-muted);
  font-family: var(--font-mono);
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 20px;
}

/* ==========================================================================
   响应式适配
   ========================================================================== */
@media (max-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .platform-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .review-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .trust-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .foot-grid {
    grid-template-columns: 1fr 1fr;
  }
  .tech-grid {
    grid-template-columns: 1fr;
  }
  .news-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .site-nav {
    position: fixed;
    top: 72px;
    left: 0;
    width: 100%;
    background: rgba(2, 8, 23, 0.98);
    border-bottom: 1px solid var(--hud-border);
    flex-direction: column;
    padding: 20px;
    display: none;
    box-shadow: 0 10px 30px rgba(0,0,0,0.8);
  }
  .site-nav.open {
    display: flex;
  }
  .nav-toggle {
    display: block;
  }
  .hero-content h1 {
    font-size: 32px;
  }
  .sell-points {
    grid-template-columns: 1fr;
  }
  .platform-grid {
    grid-template-columns: 1fr 1fr;
  }
  .stats-grid {
    grid-template-columns: 1fr 1fr;
  }
  .feature-grid {
    grid-template-columns: 1fr;
  }
  .review-grid {
    grid-template-columns: 1fr;
  }
  .trust-grid {
    grid-template-columns: 1fr;
  }
  .foot-grid {
    grid-template-columns: 1fr;
  }
  .hfc-top, .hfc-bot {
    position: static;
    margin-top: 12px;
  }
}