/* ==========================================================================
   抖云加速 (douyunjiasu.homes) — 纯原生 CSS 极速样式表
   零外部框架、零构建依赖、GPU 加速动态背景
   ========================================================================== */

:root {
  --bg-base: #050814;
  --bg-surface: rgba(13, 20, 40, 0.72);
  --bg-surface-strong: rgba(15, 24, 48, 0.9);
  --bg-card-hover: rgba(20, 32, 62, 0.88);
  --border-subtle: rgba(148, 163, 184, 0.16);
  --border-glow: rgba(34, 211, 238, 0.42);
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --cyan: #22d3ee;
  --blue: #3b82f6;
  --indigo: #8b5cf6;
  --emerald: #34d399;
  --amber: #fbbf24;
  --grad-brand: linear-gradient(135deg, #22d3ee 0%, #3b82f6 52%, #8b5cf6 100%);
  --grad-cta: linear-gradient(135deg, #06b6d4 0%, #2563eb 100%);
  --shadow-card: 0 18px 45px -18px rgba(2, 6, 23, 0.85);
  --shadow-glow: 0 10px 35px -8px rgba(34, 211, 238, 0.35);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 22px;
  --container-max: 1240px;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  background-color: var(--bg-base);
  color: var(--text-primary);
  font-family: var(--font-sans);
  line-height: 1.7;
}

body {
  margin: 0;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background-color: transparent;
  color: var(--text-primary);
}

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

a {
  color: var(--cyan);
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease, transform 0.2s ease;
}

a:hover {
  color: #67e8f9;
}

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

/* --------------------------------------------------------------------------
   动态极光与脉冲矩阵背景（纯 CSS GPU 合成，零 JS 开销）
   -------------------------------------------------------------------------- */

.bg-stage {
  position: fixed;
  inset: 0;
  z-index: 0;
  overflow: hidden;
  pointer-events: none;
  background:
    radial-gradient(circle at 18% 12%, rgba(34, 211, 238, 0.12), transparent 42%),
    radial-gradient(circle at 84% 22%, rgba(59, 130, 246, 0.14), transparent 46%),
    radial-gradient(circle at 50% 88%, rgba(139, 92, 246, 0.12), transparent 48%),
    linear-gradient(180deg, #040712 0%, #070c1e 50%, #050814 100%);
}

.bg-grid {
  position: absolute;
  inset: -120px;
  background-image:
    linear-gradient(to right, rgba(56, 189, 248, 0.06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(56, 189, 248, 0.06) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 80% 70% at 50% 35%, #000 35%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 80% 70% at 50% 35%, #000 35%, transparent 100%);
  animation: gridDrift 28s linear infinite;
  will-change: transform;
}

.bg-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.45;
  will-change: transform;
}

.bg-orb--cyan {
  width: 520px;
  height: 520px;
  top: -120px;
  left: -80px;
  background: radial-gradient(circle, rgba(34, 211, 238, 0.36) 0%, rgba(34, 211, 238, 0) 70%);
  animation: orbFloatA 18s ease-in-out infinite alternate;
}

.bg-orb--blue {
  width: 620px;
  height: 620px;
  top: 22%;
  right: -160px;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.34) 0%, rgba(59, 130, 246, 0) 70%);
  animation: orbFloatB 22s ease-in-out infinite alternate;
}

.bg-orb--violet {
  width: 560px;
  height: 560px;
  bottom: -160px;
  left: 28%;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.3) 0%, rgba(139, 92, 246, 0) 70%);
  animation: orbFloatC 25s ease-in-out infinite alternate;
}

.bg-beams {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.bg-beam {
  position: absolute;
  width: 2px;
  height: 180px;
  background: linear-gradient(180deg, rgba(34, 211, 238, 0) 0%, rgba(34, 211, 238, 0.65) 55%, rgba(139, 92, 246, 0) 100%);
  opacity: 0.38;
  animation: beamFall 9s linear infinite;
  will-change: transform, opacity;
}

.bg-beam:nth-child(1) { left: 12%; animation-duration: 8.5s; animation-delay: -1s; }
.bg-beam:nth-child(2) { left: 31%; animation-duration: 11s; animation-delay: -5s; }
.bg-beam:nth-child(3) { left: 56%; animation-duration: 9.5s; animation-delay: -3s; }
.bg-beam:nth-child(4) { left: 78%; animation-duration: 12.5s; animation-delay: -7s; }
.bg-beam:nth-child(5) { left: 91%; animation-duration: 10s; animation-delay: -2s; }

/* 各种各样漂浮的动态小云朵 */
.bg-clouds {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.bg-cloud {
  position: absolute;
  left: 0;
  will-change: transform, opacity;
  filter: drop-shadow(0 0 12px rgba(56, 189, 248, 0.22));
}

.bg-cloud svg {
  display: block;
  width: 100%;
  height: auto;
  animation: cloudBob 6s ease-in-out infinite alternate;
  will-change: transform;
}

.bg-cloud--1  { top: 7%;  width: 118px; color: rgba(103, 232, 249, 0.26); animation: cloudDriftR 34s linear infinite -7s; }
.bg-cloud--2  { top: 14%; width: 76px;  color: rgba(147, 197, 253, 0.28); animation: cloudDriftL 29s linear infinite -14s; }
.bg-cloud--3  { top: 22%; width: 136px; color: rgba(129, 140, 248, 0.24); animation: cloudDriftR 42s linear infinite -23s; }
.bg-cloud--4  { top: 31%; width: 68px;  color: rgba(34, 211, 238, 0.30);  animation: cloudDriftR 25s linear infinite -12s; }
.bg-cloud--5  { top: 41%; width: 108px; color: rgba(96, 165, 250, 0.24);  animation: cloudDriftL 38s linear infinite -19s; }
.bg-cloud--6  { top: 50%; width: 88px;  color: rgba(167, 139, 250, 0.26); animation: cloudDriftR 31s linear infinite -4s; }
.bg-cloud--7  { top: 59%; width: 145px; color: rgba(56, 189, 248, 0.20);  animation: cloudDriftL 46s linear infinite -29s; }
.bg-cloud--8  { top: 68%; width: 74px;  color: rgba(103, 232, 249, 0.28); animation: cloudDriftR 27s linear infinite -16s; }
.bg-cloud--9  { top: 77%; width: 122px; color: rgba(96, 165, 250, 0.24);  animation: cloudDriftL 36s linear infinite -9s; }
.bg-cloud--10 { top: 86%; width: 92px;  color: rgba(167, 139, 250, 0.26); animation: cloudDriftR 33s linear infinite -21s; }
.bg-cloud--11 { top: 18%; width: 58px;  color: rgba(186, 230, 253, 0.32); animation: cloudDriftL 24s linear infinite -5s; }
.bg-cloud--12 { top: 73%; width: 62px;  color: rgba(34, 211, 238, 0.30);  animation: cloudDriftR 28s linear infinite -24s; }

.bg-cloud--2 svg, .bg-cloud--6 svg, .bg-cloud--10 svg { animation-duration: 7.5s; animation-delay: -2s; }
.bg-cloud--3 svg, .bg-cloud--7 svg, .bg-cloud--11 svg { animation-duration: 5.2s; animation-delay: -4s; }
.bg-cloud--4 svg, .bg-cloud--8 svg, .bg-cloud--12 svg { animation-duration: 8.4s; animation-delay: -1s; }

@keyframes cloudDriftR {
  0%   { transform: translate3d(-18vw, 0, 0); }
  100% { transform: translate3d(116vw, 0, 0); }
}

@keyframes cloudDriftL {
  0%   { transform: translate3d(116vw, 0, 0); }
  100% { transform: translate3d(-18vw, 0, 0); }
}

@keyframes cloudBob {
  0%   { transform: translate3d(0, -8px, 0) scale(1); }
  100% { transform: translate3d(0, 10px, 0) scale(1.04); }
}

@keyframes gridDrift {
  0% { transform: translate3d(0, 0, 0); }
  100% { transform: translate3d(64px, 64px, 0); }
}

@keyframes orbFloatA {
  0% { transform: translate3d(0, 0, 0) scale(1); }
  100% { transform: translate3d(110px, 85px, 0) scale(1.14); }
}

@keyframes orbFloatB {
  0% { transform: translate3d(0, 0, 0) scale(1.06); }
  100% { transform: translate3d(-120px, -65px, 0) scale(0.94); }
}

@keyframes orbFloatC {
  0% { transform: translate3d(0, 0, 0) scale(0.95); }
  100% { transform: translate3d(85px, -90px, 0) scale(1.12); }
}

@keyframes beamFall {
  0% { transform: translate3d(0, -220px, 0); opacity: 0; }
  20% { opacity: 0.45; }
  80% { opacity: 0.35; }
  100% { transform: translate3d(0, 110vh, 0); opacity: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .bg-grid,
  .bg-orb,
  .bg-beam,
  .bg-cloud,
  .bg-cloud svg {
    animation: none;
  }
}

/* --------------------------------------------------------------------------
   通用容器与排版
   -------------------------------------------------------------------------- */

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.section {
  padding: 4.5rem 0;
  position: relative;
}

.section--compact {
  padding: 3rem 0;
}

.section-header {
  text-align: center;
  max-width: 780px;
  margin: 0 auto 2.75rem;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.38rem 0.95rem;
  border-radius: 999px;
  background: rgba(34, 211, 238, 0.1);
  border: 1px solid rgba(34, 211, 238, 0.28);
  color: var(--cyan);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  margin-bottom: 1rem;
}

.eyebrow-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 10px var(--cyan);
}

.section-title {
  margin: 0 0 0.85rem;
  font-size: clamp(1.65rem, 3vw, 2.35rem);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.015em;
}

.section-subtitle {
  margin: 0;
  color: var(--text-muted);
  font-size: 1.02rem;
}

.grad-text {
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* --------------------------------------------------------------------------
   顶部导航栏（左上方 Logo + 锚点跳转 + 立即注册 CTA）
   -------------------------------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(5, 8, 20, 0.78);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-subtle);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 72px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.72rem;
  color: var(--text-primary);
  flex-shrink: 0;
}

.brand:hover {
  color: var(--text-primary);
}

.brand-logo {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: #ffffff;
  box-shadow: 0 0 18px rgba(34, 211, 238, 0.25);
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand-name {
  font-size: 1.16rem;
  font-weight: 800;
  letter-spacing: 0.02em;
}

.brand-tag {
  font-size: 0.68rem;
  font-weight: 600;
  color: var(--cyan);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 1.35rem;
  overflow-x: auto;
  scrollbar-width: none;
}

.main-nav::-webkit-scrollbar {
  display: none;
}

.main-nav a {
  color: var(--text-secondary);
  font-size: 0.94rem;
  font-weight: 500;
  white-space: nowrap;
  padding: 0.35rem 0.1rem;
  position: relative;
}

.main-nav a:hover {
  color: var(--cyan);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

/* 按钮规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  padding: 0.72rem 1.35rem;
  border-radius: var(--radius-sm);
  font-weight: 700;
  font-size: 0.95rem;
  line-height: 1.2;
  cursor: pointer;
  border: 1px solid transparent;
  white-space: nowrap;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

.btn--primary {
  background: var(--grad-cta);
  color: #ffffff;
  box-shadow: var(--shadow-glow);
}

.btn--primary:hover {
  color: #ffffff;
  transform: translateY(-2px);
  box-shadow: 0 14px 34px -6px rgba(34, 211, 238, 0.5);
}

.btn--outline {
  background: rgba(15, 23, 42, 0.65);
  color: var(--text-primary);
  border-color: rgba(56, 189, 248, 0.35);
}

.btn--outline:hover {
  color: var(--cyan);
  border-color: var(--cyan);
  background: rgba(34, 211, 238, 0.08);
  transform: translateY(-2px);
}

.btn--sm {
  padding: 0.54rem 1.05rem;
  font-size: 0.88rem;
}

.btn--block {
  width: 100%;
}

/* --------------------------------------------------------------------------
   Hero 首屏区域
   -------------------------------------------------------------------------- */

.hero {
  padding: 4.5rem 0 3.25rem;
}

.hero-card {
  position: relative;
  padding: 3.4rem 2.4rem;
  border-radius: var(--radius-lg);
  background: linear-gradient(155deg, rgba(15, 24, 48, 0.68) 0%, rgba(9, 14, 30, 0.76) 100%);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(56, 189, 248, 0.22);
  box-shadow: var(--shadow-card);
  text-align: center;
  overflow: hidden;
}

.hero-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: var(--grad-brand);
  opacity: 0.85;
}

.hero-title {
  margin: 0 auto 1.15rem;
  max-width: 920px;
  font-size: clamp(2rem, 4.4vw, 3.25rem);
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: -0.02em;
}

.hero-desc {
  margin: 0 auto 2rem;
  max-width: 790px;
  font-size: clamp(1rem, 1.5vw, 1.14rem);
  color: var(--text-secondary);
}

.hero-cta-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 2.5rem;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  text-align: left;
}

.stat-item {
  padding: 1rem 1.15rem;
  border-radius: var(--radius-md);
  background: rgba(15, 23, 42, 0.65);
  border: 1px solid var(--border-subtle);
}

.stat-value {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--cyan);
  margin-bottom: 0.2rem;
}

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

/* --------------------------------------------------------------------------
   价格方案模块（严格同排 4 列布局）
   -------------------------------------------------------------------------- */

.pricing-row {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1.15rem;
  align-items: stretch;
}

.price-card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 1.65rem 1.35rem;
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(10px);
  transition: transform 0.22s ease, border-color 0.22s ease, background 0.22s ease;
}

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

.price-card--featured {
  background: linear-gradient(175deg, rgba(19, 34, 68, 0.92) 0%, rgba(11, 20, 42, 0.94) 100%);
  border: 1.5px solid rgba(34, 211, 238, 0.62);
  box-shadow: 0 22px 50px -15px rgba(34, 211, 238, 0.28);
}

.price-badge {
  position: absolute;
  top: -12px;
  right: 16px;
  padding: 0.22rem 0.72rem;
  border-radius: 999px;
  background: var(--grad-brand);
  color: #040712;
  font-size: 0.74rem;
  font-weight: 800;
  letter-spacing: 0.03em;
}

.price-tier {
  font-size: 1.14rem;
  font-weight: 800;
  margin: 0 0 0.3rem;
  color: var(--text-primary);
}

.price-tagline {
  font-size: 0.84rem;
  color: var(--text-muted);
  margin: 0 0 1.1rem;
  min-height: 2.6em;
}

.price-figure {
  display: flex;
  align-items: baseline;
  gap: 0.25rem;
  margin-bottom: 0.35rem;
}

.price-currency {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--cyan);
}

.price-amount {
  font-size: 2.2rem;
  font-weight: 900;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.price-unit {
  font-size: 0.88rem;
  color: var(--text-muted);
}

.price-cycles {
  font-size: 0.8rem;
  color: var(--emerald);
  background: rgba(52, 211, 153, 0.08);
  border: 1px solid rgba(52, 211, 153, 0.2);
  border-radius: 8px;
  padding: 0.38rem 0.62rem;
  margin-bottom: 1.15rem;
}

.price-list {
  list-style: none;
  margin: 0 0 1.45rem;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.58rem;
  font-size: 0.88rem;
  color: var(--text-secondary);
  flex-grow: 1;
}

.price-list li {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
}

.price-list li::before {
  content: "✓";
  color: var(--cyan);
  font-weight: 800;
  flex-shrink: 0;
}

.pricing-note {
  margin-top: 1.25rem;
  text-align: center;
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* GEO 对比表格 */
.table-wrap {
  margin-top: 2.25rem;
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface-strong);
}

.compare-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 680px;
  font-size: 0.92rem;
}

.compare-table th,
.compare-table td {
  padding: 0.92rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-subtle);
}

.compare-table thead th {
  background: rgba(34, 211, 238, 0.08);
  color: var(--cyan);
  font-weight: 700;
}

.compare-table tbody tr:last-child td {
  border-bottom: none;
}

.compare-table tbody tr:hover {
  background: rgba(56, 189, 248, 0.04);
}

/* --------------------------------------------------------------------------
   核心优势 & 节点矩阵
   -------------------------------------------------------------------------- */

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}

.card {
  padding: 1.55rem;
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(10px);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

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

.card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: rgba(34, 211, 238, 0.12);
  border: 1px solid rgba(34, 211, 238, 0.25);
  color: var(--cyan);
  font-size: 1.25rem;
  font-weight: 800;
  margin-bottom: 1rem;
}

.card h3 {
  margin: 0 0 0.55rem;
  font-size: 1.12rem;
  font-weight: 700;
}

.card p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.94rem;
}

.node-box {
  padding: 1.65rem;
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
}

.node-box h3 {
  margin: 0 0 0.75rem;
  font-size: 1.12rem;
  color: var(--cyan);
}

.chip-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.chip {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.78rem;
  border-radius: 999px;
  font-size: 0.84rem;
  font-weight: 600;
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(148, 163, 184, 0.22);
  color: var(--text-secondary);
}

.chip--hot {
  border-color: rgba(34, 211, 238, 0.38);
  color: #a5f3fc;
  background: rgba(34, 211, 238, 0.08);
}

/* --------------------------------------------------------------------------
   专题文章卡片网格
   -------------------------------------------------------------------------- */

.articles-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}

.article-card {
  display: flex;
  flex-direction: column;
  padding: 1.6rem;
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-card);
  transition: transform 0.2s ease, border-color 0.2s ease;
}

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

.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-bottom: 0.8rem;
}

.tag {
  display: inline-block;
  padding: 0.2rem 0.62rem;
  border-radius: 6px;
  font-size: 0.76rem;
  font-weight: 600;
  background: rgba(59, 130, 246, 0.14);
  color: #93c5fd;
  border: 1px solid rgba(59, 130, 246, 0.26);
}

.article-card h3 {
  margin: 0 0 0.6rem;
  font-size: 1.15rem;
  line-height: 1.4;
}

.article-card h3 a {
  color: var(--text-primary);
}

.article-card h3 a:hover {
  color: var(--cyan);
}

.article-card p {
  margin: 0 0 1.1rem;
  color: var(--text-muted);
  font-size: 0.93rem;
  flex-grow: 1;
}

.article-card-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.86rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-subtle);
  padding-top: 0.85rem;
}

/* --------------------------------------------------------------------------
   用户评价模块
   -------------------------------------------------------------------------- */

.review-card {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.review-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.review-user {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--grad-brand);
  color: #040712;
  font-weight: 800;
  font-size: 0.95rem;
  flex-shrink: 0;
}

.review-name {
  font-weight: 700;
  font-size: 0.98rem;
}

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

.stars {
  color: var(--amber);
  font-size: 0.92rem;
  letter-spacing: 0.08em;
}

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

.review-plan {
  font-size: 0.78rem;
  color: var(--cyan);
}

/* --------------------------------------------------------------------------
   常见问题 FAQ（纯 HTML <details> + 原生 CSS 展开）
   -------------------------------------------------------------------------- */

.faq-list {
  max-width: 920px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

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

.faq-item[open] {
  border-color: var(--border-glow);
  background: var(--bg-surface-strong);
}

.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 1.15rem 1.35rem;
  font-weight: 700;
  font-size: 1.02rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  color: var(--text-primary);
}

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

.faq-item summary::after {
  content: "+";
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--cyan);
  line-height: 1;
  transition: transform 0.2s ease;
}

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

.faq-answer {
  padding: 0 1.35rem 1.2rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
  border-top: 1px solid rgba(148, 163, 184, 0.1);
  padding-top: 0.95rem;
}

/* --------------------------------------------------------------------------
   外链资源与页脚 CTA
   -------------------------------------------------------------------------- */

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

.ext-link-card {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  padding: 1.15rem 1.25rem;
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
}

.ext-link-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-2px);
}

.ext-link-title {
  font-weight: 700;
  color: var(--cyan);
  font-size: 0.98rem;
}

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

.cta-banner {
  padding: 2.6rem 2rem;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(16, 36, 72, 0.9) 0%, rgba(28, 22, 68, 0.88) 100%);
  border: 1px solid rgba(34, 211, 238, 0.36);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  box-shadow: var(--shadow-card);
}

.cta-banner h2 {
  margin: 0 0 0.45rem;
  font-size: clamp(1.35rem, 2.5vw, 1.85rem);
}

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

.site-footer {
  border-top: 1px solid var(--border-subtle);
  background: rgba(4, 7, 18, 0.85);
  padding: 3rem 0 2.2rem;
  margin-top: 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-col h4 {
  margin: 0 0 0.85rem;
  font-size: 0.96rem;
  color: var(--text-primary);
}

.footer-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.48rem;
  font-size: 0.88rem;
}

.footer-links a {
  color: var(--text-muted);
}

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

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.84rem;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   文章内页专属排版
   -------------------------------------------------------------------------- */

.article-layout {
  padding: 2.8rem 0 4rem;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 1.4rem;
}

.article-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 2rem;
  align-items: start;
}

.article-body {
  padding: 2.2rem 2.3rem;
  border-radius: var(--radius-lg);
  background: var(--bg-surface-strong);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-card);
}

.article-body h1 {
  margin: 0 0 1rem;
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  line-height: 1.3;
}

.article-info {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.86rem;
  color: var(--text-muted);
  padding-bottom: 1.2rem;
  margin-bottom: 1.4rem;
  border-bottom: 1px solid var(--border-subtle);
}

.tldr-box {
  padding: 1.15rem 1.25rem;
  border-radius: var(--radius-md);
  background: rgba(34, 211, 238, 0.08);
  border-left: 4px solid var(--cyan);
  margin-bottom: 1.75rem;
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.tldr-box strong {
  color: var(--cyan);
}

.article-content h2 {
  margin: 2rem 0 0.75rem;
  font-size: 1.34rem;
  color: var(--text-primary);
  padding-left: 0.75rem;
  border-left: 3px solid var(--blue);
}

.article-content h3 {
  margin: 1.35rem 0 0.55rem;
  font-size: 1.1rem;
  color: #bae6fd;
}

.article-content p {
  margin: 0 0 1.05rem;
  color: var(--text-secondary);
  font-size: 1.01rem;
  line-height: 1.85;
}

.article-content ul,
.article-content ol {
  margin: 0 0 1.2rem;
  padding-left: 1.35rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

.article-content li {
  margin-bottom: 0.45rem;
}

.article-cta-inline {
  margin: 1.9rem 0;
  padding: 1.35rem 1.5rem;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, rgba(16, 36, 72, 0.85), rgba(20, 24, 58, 0.9));
  border: 1px solid rgba(34, 211, 238, 0.35);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.article-cta-inline p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--text-primary);
}

.article-sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  position: sticky;
  top: 92px;
}

.sidebar-card {
  padding: 1.35rem;
  border-radius: var(--radius-md);
  background: var(--bg-surface-strong);
  border: 1px solid var(--border-subtle);
}

.sidebar-card h3 {
  margin: 0 0 0.85rem;
  font-size: 1.04rem;
  color: var(--cyan);
}

.sidebar-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  font-size: 0.9rem;
}

.sidebar-list a {
  color: var(--text-secondary);
  line-height: 1.45;
  display: block;
}

.sidebar-list a:hover {
  color: var(--cyan);
}

.article-nav {
  margin-top: 2.2rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--border-subtle);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.article-nav-card {
  padding: 0.95rem 1.1rem;
  border-radius: var(--radius-sm);
  background: rgba(15, 23, 42, 0.72);
  border: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

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

.article-nav-label {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.article-nav-title {
  font-size: 0.94rem;
  font-weight: 700;
  color: var(--text-primary);
}

/* --------------------------------------------------------------------------
   响应式断点（注意：pricing-row 在任何宽度下均保持单排横向布局）
   -------------------------------------------------------------------------- */

@media (max-width: 1080px) {
  .pricing-row {
    grid-template-columns: none;
    grid-auto-flow: column;
    grid-auto-columns: minmax(255px, 1fr);
    overflow-x: auto;
    padding-bottom: 0.85rem;
    scroll-snap-type: x mandatory;
  }

  .price-card {
    scroll-snap-align: start;
  }

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

  .article-sidebar {
    position: static;
  }

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

@media (max-width: 820px) {
  .hero-stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .grid-3,
  .links-grid,
  .articles-grid,
  .grid-2 {
    grid-template-columns: 1fr;
  }

  .article-body {
    padding: 1.5rem 1.25rem;
  }

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

@media (max-width: 600px) {
  .header-inner {
    flex-wrap: wrap;
    padding: 0.7rem 0;
  }

  .main-nav {
    order: 3;
    width: 100%;
    padding-top: 0.45rem;
    border-top: 1px solid rgba(148, 163, 184, 0.12);
  }

  .hero {
    padding-top: 2.5rem;
  }

  .hero-card {
    padding: 2.1rem 1.25rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }
}