/* ==========================================================================
   Foo&Friends 机场 (fnfjichang.sbs) — 原生零依赖极速样式表
   纯 HTML5 + 原生 CSS3 | 零 JS 框架 | 动态极光背景 | 价格同排自适应布局
   ========================================================================== */

:root {
  --bg-base: #06090e;
  --bg-surface: rgba(13, 19, 29, 0.78);
  --bg-surface-strong: rgba(16, 24, 38, 0.92);
  --bg-card-hover: rgba(20, 32, 48, 0.9);
  --border-subtle: rgba(148, 163, 184, 0.14);
  --border-emerald: rgba(16, 185, 129, 0.42);
  --border-amber: rgba(245, 158, 11, 0.45);

  --text-primary: #f1f5f9;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;

  --emerald-400: #34d399;
  --emerald-500: #10b981;
  --emerald-600: #059669;
  --sky-400: #38bdf8;
  --sky-500: #0ea5e9;
  --amber-400: #fbbf24;
  --amber-500: #f59e0b;

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 22px;
  --shadow-card: 0 18px 42px -18px rgba(0, 0, 0, 0.75);
  --shadow-glow: 0 0 36px -10px rgba(16, 185, 129, 0.35);

  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-base);
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-sans);
  color: var(--text-primary);
  background: transparent;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  position: relative;
}

main,
.site-footer {
  position: relative;
  z-index: 1;
}

a {
  color: inherit;
  text-decoration: none;
}

img,
svg {
  display: block;
  max-width: 100%;
}

/* ==========================================================================
   动态背景系统 (Pure CSS Animated Aurora + Matrix Grid)
   ========================================================================== */

.aurora-stage {
  position: fixed;
  inset: 0;
  z-index: 0;
  overflow: hidden;
  pointer-events: none;
  background: radial-gradient(circle at 50% 0%, #0b1622 0%, #06090e 70%);
}

.aurora-grid {
  position: absolute;
  inset: -120px;
  background-image:
    linear-gradient(to right, rgba(52, 211, 153, 0.085) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(56, 189, 248, 0.07) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 85% 75% at 50% 40%, #000 40%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 85% 75% at 50% 40%, #000 40%, transparent 100%);
  animation: gridDrift 24s linear infinite;
}

.aurora-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(84px);
  opacity: 0.56;
  will-change: transform, opacity;
}

.aurora-orb-1 {
  width: 560px;
  height: 560px;
  top: -160px;
  left: -120px;
  background: radial-gradient(circle, rgba(16, 185, 129, 0.55) 0%, rgba(16, 185, 129, 0) 70%);
  animation: auroraFloatA 18s ease-in-out infinite alternate;
}

.aurora-orb-2 {
  width: 620px;
  height: 620px;
  top: 12%;
  right: -180px;
  background: radial-gradient(circle, rgba(14, 165, 233, 0.48) 0%, rgba(14, 165, 233, 0) 70%);
  animation: auroraFloatB 22s ease-in-out infinite alternate;
}

.aurora-orb-3 {
  width: 520px;
  height: 520px;
  bottom: -140px;
  left: 28%;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.36) 0%, rgba(52, 211, 153, 0.14) 45%, transparent 72%);
  animation: auroraFloatC 24s ease-in-out infinite alternate;
}

.aurora-scanline {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    to bottom,
    transparent 0%,
    rgba(52, 211, 153, 0.03) 50%,
    transparent 100%
  );
  height: 220px;
  animation: scanBeam 11s ease-in-out infinite;
}

/* 纯 CSS 落叶飘落动效 (无 JS · GPU 合成加速) */
.leaf-layer {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.leaf {
  position: absolute;
  top: -8vh;
  width: 24px;
  height: 24px;
  color: rgba(251, 191, 36, 0.85);
  filter: drop-shadow(0 0 8px rgba(245, 158, 11, 0.32));
  opacity: 0;
  will-change: transform, opacity;
}

.leaf svg {
  width: 100%;
  height: 100%;
  display: block;
}

.leaf:nth-child(3n) {
  color: rgba(52, 211, 153, 0.8);
  filter: drop-shadow(0 0 8px rgba(16, 185, 129, 0.3));
}

.leaf:nth-child(4n) {
  color: rgba(251, 146, 60, 0.85);
  filter: drop-shadow(0 0 8px rgba(249, 115, 22, 0.3));
}

.leaf:nth-child(1)  { left: 4%;  width: 20px; height: 20px; animation: leafFallA 13s linear -2s infinite; }
.leaf:nth-child(2)  { left: 11%; width: 26px; height: 26px; animation: leafFallB 16s linear -7s infinite; }
.leaf:nth-child(3)  { left: 18%; width: 19px; height: 19px; animation: leafFallC 14s linear -11s infinite; }
.leaf:nth-child(4)  { left: 26%; width: 28px; height: 28px; animation: leafFallA 18s linear -5s infinite; }
.leaf:nth-child(5)  { left: 33%; width: 21px; height: 21px; animation: leafFallB 12.5s linear -9s infinite; }
.leaf:nth-child(6)  { left: 41%; width: 25px; height: 25px; animation: leafFallC 17s linear -3s infinite; }
.leaf:nth-child(7)  { left: 48%; width: 20px; height: 20px; animation: leafFallA 15s linear -13s infinite; }
.leaf:nth-child(8)  { left: 56%; width: 28px; height: 28px; animation: leafFallB 19s linear -6s infinite; }
.leaf:nth-child(9)  { left: 63%; width: 22px; height: 22px; animation: leafFallC 13.5s linear -10s infinite; }
.leaf:nth-child(10) { left: 71%; width: 24px; height: 24px; animation: leafFallA 16.5s linear -1s infinite; }
.leaf:nth-child(11) { left: 78%; width: 19px; height: 19px; animation: leafFallB 14.5s linear -8s infinite; }
.leaf:nth-child(12) { left: 85%; width: 27px; height: 27px; animation: leafFallC 17.5s linear -12s infinite; }
.leaf:nth-child(13) { left: 91%; width: 22px; height: 22px; animation: leafFallA 15.5s linear -4s infinite; }
.leaf:nth-child(14) { left: 96%; width: 20px; height: 20px; animation: leafFallB 13.8s linear -14s infinite; }

@keyframes leafFallA {
  0% {
    transform: translate3d(0, -10vh, 0) rotate(0deg) rotateY(0deg);
    opacity: 0;
  }
  8% {
    opacity: 0.85;
  }
  25% {
    transform: translate3d(42px, 24vh, 0) rotate(75deg) rotateY(140deg);
  }
  50% {
    transform: translate3d(-28px, 54vh, 0) rotate(165deg) rotateY(280deg);
  }
  75% {
    transform: translate3d(38px, 84vh, 0) rotate(260deg) rotateY(400deg);
    opacity: 0.78;
  }
  100% {
    transform: translate3d(-18px, 114vh, 0) rotate(350deg) rotateY(520deg);
    opacity: 0;
  }
}

@keyframes leafFallB {
  0% {
    transform: translate3d(0, -10vh, 0) rotate(25deg) rotateX(0deg);
    opacity: 0;
  }
  10% {
    opacity: 0.78;
  }
  30% {
    transform: translate3d(-46px, 28vh, 0) rotate(-65deg) rotateX(160deg);
  }
  60% {
    transform: translate3d(34px, 64vh, 0) rotate(-175deg) rotateX(320deg);
  }
  85% {
    transform: translate3d(-32px, 94vh, 0) rotate(-270deg) rotateX(460deg);
    opacity: 0.72;
  }
  100% {
    transform: translate3d(20px, 114vh, 0) rotate(-360deg) rotateX(540deg);
    opacity: 0;
  }
}

@keyframes leafFallC {
  0% {
    transform: translate3d(0, -10vh, 0) rotate(-15deg) rotateZ(0deg);
    opacity: 0;
  }
  10% {
    opacity: 0.82;
  }
  28% {
    transform: translate3d(52px, 26vh, 0) rotate(90deg) scale(0.95);
  }
  55% {
    transform: translate3d(-36px, 58vh, 0) rotate(195deg) scale(1.06);
  }
  82% {
    transform: translate3d(28px, 88vh, 0) rotate(290deg) scale(0.92);
    opacity: 0.74;
  }
  100% {
    transform: translate3d(-24px, 114vh, 0) rotate(385deg) scale(1);
    opacity: 0;
  }
}

@keyframes gridDrift {
  0% {
    transform: translate3d(0, 0, 0);
  }
  100% {
    transform: translate3d(56px, 56px, 0);
  }
}

@keyframes auroraFloatA {
  0% {
    transform: translate3d(0, 0, 0) scale(1);
    opacity: 0.38;
  }
  100% {
    transform: translate3d(90px, 70px, 0) scale(1.14);
    opacity: 0.54;
  }
}

@keyframes auroraFloatB {
  0% {
    transform: translate3d(0, 0, 0) scale(1.05);
    opacity: 0.34;
  }
  100% {
    transform: translate3d(-110px, 85px, 0) scale(0.94);
    opacity: 0.5;
  }
}

@keyframes auroraFloatC {
  0% {
    transform: translate3d(0, 0, 0) scale(0.95);
    opacity: 0.3;
  }
  100% {
    transform: translate3d(70px, -90px, 0) scale(1.12);
    opacity: 0.45;
  }
}

@keyframes scanBeam {
  0% {
    transform: translateY(-220px);
    opacity: 0;
  }
  20% {
    opacity: 1;
  }
  80% {
    opacity: 1;
  }
  100% {
    transform: translateY(100vh);
    opacity: 0;
  }
}

/* ==========================================================================
   布局容器与通用工具类
   ========================================================================== */

.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 22px;
}

.section {
  padding: 76px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 44px;
}

.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 14px;
  border-radius: 999px;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(52, 211, 153, 0.3);
  color: var(--emerald-400);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-bottom: 14px;
}

.section-title {
  margin: 0 0 12px;
  font-size: clamp(1.65rem, 3vw, 2.35rem);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.section-desc {
  margin: 0;
  color: var(--text-muted);
  font-size: 1rem;
}

.gradient-text {
  background: linear-gradient(120deg, #34d399 0%, #38bdf8 55%, #a7f3d0 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ==========================================================================
   顶部导航栏 (左上方 Logo + 导航 + 立即注册 CTA)
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(6, 9, 14, 0.78);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 72px;
}

.brand-logo-link {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.brand-logo-link:hover {
  transform: translateY(-1px);
  opacity: 0.94;
}

.brand-logo-img {
  height: 44px;
  width: auto;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.main-nav a {
  padding: 7px 12px;
  border-radius: 8px;
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.2s ease, background-color 0.2s ease;
}

.main-nav a:hover,
.main-nav a:focus-visible {
  color: var(--emerald-400);
  background: rgba(16, 185, 129, 0.1);
  outline: none;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: 12px;
  font-weight: 700;
  font-size: 0.95rem;
  line-height: 1.2;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease, border-color 0.2s ease;
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #10b981 0%, #059669 100%);
  color: #03150e;
  box-shadow: 0 10px 26px -8px rgba(16, 185, 129, 0.55);
}

.btn-primary:hover,
.btn-primary:focus-visible {
  transform: translateY(-2px);
  box-shadow: 0 14px 32px -6px rgba(52, 211, 153, 0.65);
  background: linear-gradient(135deg, #34d399 0%, #10b981 100%);
  outline: none;
}

.btn-secondary {
  background: rgba(15, 23, 42, 0.72);
  color: var(--text-primary);
  border-color: rgba(148, 163, 184, 0.28);
}

.btn-secondary:hover,
.btn-secondary:focus-visible {
  border-color: var(--emerald-400);
  color: var(--emerald-400);
  transform: translateY(-2px);
  outline: none;
}

.btn-sm {
  padding: 9px 16px;
  font-size: 0.88rem;
  border-radius: 10px;
}

/* ==========================================================================
   Hero 首屏区域 (左侧品牌核心价值 + 右侧实时节点拓扑卡片)
   ========================================================================== */

.hero-section {
  padding: 64px 0 56px;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 36px;
  align-items: center;
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 15px;
  border-radius: 999px;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(52, 211, 153, 0.32);
  color: var(--emerald-400);
  font-size: 0.84rem;
  font-weight: 600;
  margin-bottom: 20px;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #34d399;
  box-shadow: 0 0 0 0 rgba(52, 211, 153, 0.7);
  animation: pulseBeacon 2s infinite;
}

@keyframes pulseBeacon {
  0% {
    box-shadow: 0 0 0 0 rgba(52, 211, 153, 0.75);
  }
  70% {
    box-shadow: 0 0 0 9px rgba(52, 211, 153, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(52, 211, 153, 0);
  }
}

.hero-title {
  margin: 0 0 18px;
  font-size: clamp(2rem, 4.1vw, 3.15rem);
  font-weight: 850;
  line-height: 1.18;
  letter-spacing: -0.025em;
}

.hero-lead {
  margin: 0 0 26px;
  font-size: 1.07rem;
  color: var(--text-secondary);
  max-width: 620px;
}

.hero-cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 28px;
}

.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.metric-chip {
  padding: 13px 14px;
  border-radius: var(--radius-sm);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  backdrop-filter: blur(10px);
}

.metric-value {
  display: block;
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--emerald-400);
  line-height: 1.2;
}

.metric-label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 3px;
}

/* 右侧动态路由拓扑卡片 */
.telemetry-card {
  background: var(--bg-surface-strong);
  border: 1px solid rgba(52, 211, 153, 0.25);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-card), var(--shadow-glow);
  position: relative;
  overflow: hidden;
}

.telemetry-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, #34d399, #38bdf8, transparent);
}

.telemetry-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 18px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.telemetry-title {
  font-size: 0.96rem;
  font-weight: 700;
  color: var(--text-primary);
}

.telemetry-badge {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  padding: 3px 10px;
  border-radius: 999px;
  background: rgba(16, 185, 129, 0.14);
  color: var(--emerald-400);
  border: 1px solid rgba(52, 211, 153, 0.25);
}

.node-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 18px;
}

.node-row {
  display: grid;
  grid-template-columns: 1.65fr 0.6fr 0.85fr;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  border-radius: 10px;
  background: rgba(15, 23, 42, 0.65);
  border: 1px solid rgba(148, 163, 184, 0.1);
  font-size: 0.86rem;
}

.node-region {
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
}

.node-code {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 28px;
  height: 22px;
  padding: 0 6px;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  background: rgba(16, 185, 129, 0.16);
  color: var(--emerald-400);
  border: 1px solid rgba(52, 211, 153, 0.28);
  flex-shrink: 0;
}

.node-tag {
  font-size: 0.72rem;
  padding: 2px 7px;
  border-radius: 6px;
  background: rgba(56, 189, 248, 0.14);
  color: var(--sky-400);
  font-weight: 600;
  white-space: nowrap;
  flex-shrink: 0;
}

.node-latency {
  font-family: var(--font-mono);
  color: var(--emerald-400);
  font-weight: 700;
  text-align: right;
  white-space: nowrap;
}

.node-unlock {
  font-size: 0.76rem;
  color: var(--amber-400);
  text-align: right;
  font-weight: 600;
  white-space: nowrap;
}

.telemetry-foot {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  font-size: 0.8rem;
  color: var(--text-muted);
  padding-top: 8px;
}

/* ==========================================================================
   GEO 权威速览摘要块 (AI Search & 用户快速核验)
   ========================================================================== */

.geo-summary-box {
  background: linear-gradient(145deg, rgba(13, 24, 34, 0.9), rgba(10, 15, 24, 0.92));
  border: 1px solid rgba(52, 211, 153, 0.24);
  border-radius: var(--radius-md);
  padding: 22px 26px;
  margin-top: 26px;
}

.geo-summary-title {
  margin: 0 0 10px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--emerald-400);
}

.geo-facts-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin: 0;
}

.geo-fact {
  background: rgba(15, 23, 42, 0.55);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
  padding: 12px 14px;
}

.geo-fact dt {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.geo-fact dd {
  margin: 0;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-primary);
}

/* ==========================================================================
   套餐价格表 — 强制所有价格同排 (4列同排横向展示)
   ========================================================================== */

.plans-row-wrapper {
  width: 100%;
  overflow-x: auto;
  padding-bottom: 10px;
  scrollbar-width: thin;
  scrollbar-color: rgba(52, 211, 153, 0.45) transparent;
}

.plans-row {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  align-items: stretch;
}

.plan-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: var(--bg-surface-strong);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  position: relative;
  transition: transform 0.25s ease, border-color 0.25s ease, box-shadow 0.25s ease;
  box-shadow: var(--shadow-card);
}

.plan-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-emerald);
  box-shadow: 0 22px 44px -18px rgba(16, 185, 129, 0.28);
}

.plan-card.plan-featured {
  border-color: rgba(52, 211, 153, 0.6);
  background: linear-gradient(175deg, rgba(16, 42, 38, 0.92) 0%, rgba(13, 19, 29, 0.96) 55%);
  box-shadow: 0 20px 48px -18px rgba(16, 185, 129, 0.38);
}

.plan-ribbon {
  position: absolute;
  top: 14px;
  right: 14px;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 0.74rem;
  font-weight: 700;
  background: linear-gradient(135deg, #f59e0b, #fbbf24);
  color: #1f1300;
}

.plan-level {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  font-weight: 700;
  color: var(--emerald-400);
  letter-spacing: 0.06em;
  margin-bottom: 6px;
}

.plan-name {
  margin: 0 0 8px;
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--text-primary);
}

.plan-subtitle {
  margin: 0 0 16px;
  font-size: 0.85rem;
  color: var(--text-muted);
  min-height: 2.6em;
}

.plan-price-box {
  padding: 14px 12px;
  border-radius: 12px;
  background: rgba(6, 9, 14, 0.58);
  border: 1px solid rgba(148, 163, 184, 0.12);
  margin-bottom: 16px;
}

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

.plan-currency {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--emerald-400);
}

.plan-amount {
  font-size: 2.15rem;
  font-weight: 850;
  line-height: 1;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.plan-period {
  font-size: 0.86rem;
  color: var(--text-muted);
}

.plan-cycles {
  margin-top: 8px;
  font-size: 0.79rem;
  color: var(--sky-400);
  font-weight: 600;
}

.plan-features {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 9px;
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.plan-features li {
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.plan-features li::before {
  content: "✓";
  color: var(--emerald-400);
  font-weight: 800;
  flex-shrink: 0;
}

.plan-cta {
  width: 100%;
  text-align: center;
}

.pricing-footnote {
  margin-top: 18px;
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ==========================================================================
   核心优势与客户端生态卡片
   ========================================================================== */

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.feature-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: border-color 0.25s ease, transform 0.25s ease;
}

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

.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: rgba(16, 185, 129, 0.14);
  border: 1px solid rgba(52, 211, 153, 0.28);
  color: var(--emerald-400);
  font-weight: 800;
  font-size: 1.05rem;
  margin-bottom: 14px;
}

.feature-card h3 {
  margin: 0 0 8px;
  font-size: 1.1rem;
  font-weight: 700;
}

.feature-card p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--text-muted);
}

/* ==========================================================================
   专题评测与教程专栏 (7 篇深度文章入口 & 内部跳转)
   ========================================================================== */

.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.article-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: var(--bg-surface-strong);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 22px;
  transition: transform 0.25s ease, border-color 0.25s ease, background-color 0.25s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-emerald);
  background: var(--bg-card-hover);
}

.article-card.article-card-wide {
  grid-column: span 3;
  flex-direction: row;
  align-items: center;
  gap: 24px;
  background: linear-gradient(135deg, rgba(16, 38, 36, 0.85), rgba(13, 19, 29, 0.95));
  border-color: rgba(52, 211, 153, 0.28);
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
  font-size: 0.78rem;
}

.article-tag {
  padding: 3px 9px;
  border-radius: 6px;
  background: rgba(16, 185, 129, 0.14);
  color: var(--emerald-400);
  font-weight: 600;
}

.article-date {
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.article-card h3 {
  margin: 0 0 10px;
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1.42;
  color: var(--text-primary);
}

.article-card p {
  margin: 0 0 16px;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.article-link-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--emerald-400);
}

.article-link-more:hover {
  color: var(--sky-400);
}

/* ==========================================================================
   用户评价与口碑反馈
   ========================================================================== */

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.review-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 22px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 14px;
}

.review-stars {
  color: var(--amber-400);
  font-size: 0.96rem;
  letter-spacing: 2px;
}

.review-quote {
  margin: 0;
  font-size: 0.93rem;
  color: var(--text-secondary);
}

.review-author {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding-top: 12px;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.84rem;
}

.review-name {
  font-weight: 700;
  color: var(--text-primary);
}

.review-plan {
  font-size: 0.75rem;
  padding: 2px 9px;
  border-radius: 999px;
  background: rgba(56, 189, 248, 0.14);
  color: var(--sky-400);
  font-weight: 600;
}

/* ==========================================================================
   纯 CSS FAQ 手风琴 (<details>/<summary>)
   ========================================================================== */

.faq-list {
  max-width: 920px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

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

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

.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 18px 22px;
  font-weight: 700;
  font-size: 1.02rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

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

.faq-item summary::after {
  content: "+";
  font-size: 1.3rem;
  font-weight: 500;
  color: var(--emerald-400);
  transition: transform 0.2s ease;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-answer {
  padding: 0 22px 18px;
  color: var(--text-secondary);
  font-size: 0.94rem;
  border-top: 1px solid rgba(148, 163, 184, 0.08);
  padding-top: 14px;
}

.faq-answer a {
  color: var(--emerald-400);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ==========================================================================
   权威外链生态与页脚
   ========================================================================== */

.extlinks-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.extlink-card {
  display: block;
  padding: 18px;
  border-radius: var(--radius-sm);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.extlink-card:hover {
  border-color: var(--sky-400);
  transform: translateY(-2px);
}

.extlink-title {
  display: block;
  font-weight: 700;
  font-size: 0.96rem;
  color: var(--text-primary);
  margin-bottom: 5px;
}

.extlink-desc {
  display: block;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.cta-banner {
  background: linear-gradient(135deg, rgba(6, 78, 59, 0.55) 0%, rgba(14, 116, 144, 0.35) 100%);
  border: 1px solid rgba(52, 211, 153, 0.35);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin-top: 56px;
}

.cta-banner h2 {
  margin: 0 0 8px;
  font-size: 1.55rem;
}

.cta-banner p {
  margin: 0;
  color: var(--text-secondary);
}

.site-footer {
  border-top: 1px solid var(--border-subtle);
  padding: 44px 0 36px;
  background: rgba(4, 7, 11, 0.85);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 28px;
}

.footer-col h4 {
  margin: 0 0 12px;
  font-size: 0.94rem;
  color: var(--text-primary);
}

.footer-col ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 0.86rem;
  color: var(--text-muted);
}

.footer-col a:hover {
  color: var(--emerald-400);
}

.footer-bottom {
  padding-top: 20px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ==========================================================================
   文章内页专属排版 (articles/*.html)
   ========================================================================== */

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 310px;
  gap: 32px;
  padding: 36px 0 72px;
  align-items: start;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 0.86rem;
  color: var(--text-muted);
  margin-bottom: 18px;
}

.breadcrumb a {
  color: var(--emerald-400);
}

.article-main {
  background: var(--bg-surface-strong);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 36px 34px;
}

.article-main h1 {
  margin: 0 0 14px;
  font-size: clamp(1.55rem, 2.8vw, 2.1rem);
  line-height: 1.3;
}

.article-info-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.84rem;
  color: var(--text-muted);
  padding-bottom: 20px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--border-subtle);
}

.toc-box {
  background: rgba(16, 185, 129, 0.08);
  border: 1px solid rgba(52, 211, 153, 0.25);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  margin-bottom: 26px;
}

.toc-title {
  margin: 0 0 8px;
  font-size: 0.94rem;
  font-weight: 700;
  color: var(--emerald-400);
}

.toc-list {
  margin: 0;
  padding-left: 18px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.9rem;
}

.toc-list a {
  color: var(--text-secondary);
}

.toc-list a:hover {
  color: var(--emerald-400);
  text-decoration: underline;
}

.article-prose h2 {
  margin: 30px 0 12px;
  font-size: 1.32rem;
  color: var(--text-primary);
  padding-left: 12px;
  border-left: 3px solid var(--emerald-400);
}

.article-prose h3 {
  margin: 22px 0 10px;
  font-size: 1.08rem;
  color: var(--sky-400);
}

.article-prose p {
  margin: 0 0 16px;
  color: var(--text-secondary);
  font-size: 0.98rem;
}

.article-prose ul,
.article-prose ol {
  margin: 0 0 18px;
  padding-left: 22px;
  color: var(--text-secondary);
}

.article-prose li {
  margin-bottom: 8px;
}

.article-prose a.inline-link {
  color: var(--emerald-400);
  text-decoration: underline;
  text-underline-offset: 3px;
  font-weight: 600;
}

.data-table-wrap {
  overflow-x: auto;
  margin: 18px 0 24px;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.data-table th,
.data-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border-subtle);
}

.data-table th {
  background: rgba(16, 185, 129, 0.12);
  color: var(--emerald-400);
  font-weight: 700;
}

.article-callout {
  padding: 16px 20px;
  border-radius: var(--radius-sm);
  background: rgba(14, 165, 233, 0.1);
  border-left: 3px solid var(--sky-400);
  margin: 22px 0;
  font-size: 0.94rem;
  color: var(--text-secondary);
}

.article-nav-cards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border-subtle);
}

.article-nav-card {
  display: block;
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  background: rgba(15, 23, 42, 0.65);
  border: 1px solid var(--border-subtle);
  transition: border-color 0.2s ease;
}

.article-nav-card:hover {
  border-color: var(--emerald-400);
}

.article-nav-label {
  display: block;
  font-size: 0.76rem;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.article-nav-title {
  display: block;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-primary);
}

.article-sidebar {
  display: flex;
  flex-direction: column;
  gap: 20px;
  position: sticky;
  top: 90px;
}

.sidebar-box {
  background: var(--bg-surface-strong);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px;
}

.sidebar-box h3 {
  margin: 0 0 12px;
  font-size: 1rem;
  color: var(--emerald-400);
}

.sidebar-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 0.88rem;
}

.sidebar-links a {
  color: var(--text-secondary);
  display: block;
  padding: 6px 8px;
  border-radius: 8px;
  background: rgba(15, 23, 42, 0.45);
  border: 1px solid transparent;
}

.sidebar-links a:hover {
  border-color: var(--border-emerald);
  color: var(--emerald-400);
}

/* ==========================================================================
   响应式适配 (保持所有价格卡片始终处于同一行)
   ========================================================================== */

@media (max-width: 1080px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }

  .plans-row {
    /* 保持所有 4 个价格套餐始终同排横向排列，窄屏可流畅左右滑动 */
    grid-template-columns: repeat(4, minmax(240px, 1fr));
  }

  .features-grid,
  .articles-grid,
  .reviews-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .article-card.article-card-wide {
    grid-column: span 2;
    flex-direction: column;
    align-items: flex-start;
  }

  .extlinks-grid,
  .geo-facts-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .article-layout {
    grid-template-columns: 1fr;
  }

  .article-sidebar {
    position: static;
  }
}

@media (max-width: 720px) {
  .main-nav {
    display: none;
  }

  .hero-metrics,
  .features-grid,
  .articles-grid,
  .reviews-grid,
  .extlinks-grid,
  .geo-facts-grid,
  .footer-grid,
  .article-nav-cards {
    grid-template-columns: 1fr;
  }

  .article-card.article-card-wide {
    grid-column: span 1;
  }

  .article-main {
    padding: 24px 18px;
  }
}

/* 保留动态极光与落叶动效以确保按需呈现 */