/* ==========================================================================
   肥猫云 FeiMaoYun - 纯原生无障碍与高性能样式表
   零外部字体依赖 | 本地系统字体栈 | 键盘可访问性 | prefers-reduced-motion
   深空黑 #020617 | 等离子黄 #FCD34D | 日冕红 #EF4444
   ========================================================================== */

:root {
  --bg-primary: #020617; /* 深空黑 */
  --bg-secondary: #0b1120;
  --bg-card: rgba(15, 23, 42, 0.72);
  --bg-card-hover: rgba(30, 41, 59, 0.88);
  --primary-accent: #FCD34D; /* 等离子黄 */
  --secondary-accent: #EF4444; /* 日冕红 */
  --plasma-glow: rgba(252, 211, 77, 0.5);
  --corona-glow: rgba(239, 68, 68, 0.6);
  --border-color: rgba(252, 211, 77, 0.15);
  --border-glow: rgba(239, 68, 68, 0.45);
  --gradient-plasma: linear-gradient(135deg, #FCD34D 0%, #EF4444 100%);
  --gradient-corona: linear-gradient(135deg, #EF4444 0%, #F59E0B 100%);
  --text-main: #FFFFFF;
  --text-muted: rgba(255, 255, 255, 0.85);
  --text-dim: rgba(255, 255, 255, 0.65);
  /* 原生纯净字体栈 - 零外部网络字体加载开销 */
  --font-headline: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --container-max: 1200px;
  --radius-btn: 8px; /* 8px 圆角 */
  --radius-card: 16px;
  --radius-pill: 9999px;
  --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.8);
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-body);
  background-color: var(--bg-primary);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
  overflow-x: hidden;
  background-color: var(--bg-primary);
  position: relative;
  /* 全屏径向渐变黄/红辉光 */
  background-image: 
    radial-gradient(circle at 50% 15%, rgba(252, 211, 77, 0.16) 0%, rgba(239, 68, 68, 0.12) 35%, rgba(2, 6, 23, 0.95) 70%),
    radial-gradient(circle at 80% 60%, rgba(239, 68, 68, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 20% 80%, rgba(252, 211, 77, 0.06) 0%, transparent 50%);
  background-attachment: fixed;
}

a {
  color: inherit;
  text-decoration: none;
  transition: all 0.25s ease;
}

/* 锚点防吸顶导航遮挡 */
[id] {
  scroll-margin-top: 84px;
}

/* 全局键盘焦点追踪高亮 (:focus-visible) */
:focus-visible {
  outline: 2px dashed var(--primary-accent);
  outline-offset: 4px;
}

/* 键盘快速跳过导航通道 (Skip to Content) */
.skip-link {
  position: absolute;
  top: -120px;
  left: 20px;
  background: var(--primary-accent);
  color: #000000;
  font-weight: 800;
  padding: 12px 20px;
  border-radius: var(--radius-btn);
  z-index: 10000;
  text-decoration: none;
  box-shadow: 0 0 20px rgba(252, 211, 77, 0.8);
  transition: top 0.2s ease-in-out;
}

.skip-link:focus {
  top: 20px;
  outline: 3px solid #FFFFFF;
}

/* 屏幕阅读器专用隐藏辅助类 */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ==========================================================================
   全屏背景动效：细网格 + 3条等离子耀斑SVG + 4个上升漂移粒子
   ========================================================================== */

/* 细网格让边缘渐隐 */
.plasma-grid-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: 
    linear-gradient(rgba(252, 211, 77, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(252, 211, 77, 0.04) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at 50% 40%, black 25%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at 50% 40%, black 25%, transparent 75%);
  pointer-events: none;
  z-index: 0;
}

/* 3 条等离子耀斑 SVG (黄/红对角线，dashoffset 流动动画 2 秒一周期) */
.plasma-flares-layer {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.flare-line {
  stroke-dasharray: 260, 400;
  animation: flareFlow 2s linear infinite;
  filter: drop-shadow(0 0 8px currentColor);
}

.flare-1 {
  stroke: #FCD34D;
  stroke-width: 2.5;
  animation-duration: 2s;
}

.flare-2 {
  stroke: #EF4444;
  stroke-width: 2;
  animation-duration: 2s;
  animation-delay: -0.66s;
}

.flare-3 {
  stroke: #F59E0B;
  stroke-width: 3;
  animation-duration: 2s;
  animation-delay: -1.33s;
}

@keyframes flareFlow {
  from {
    stroke-dashoffset: 660;
  }
  to {
    stroke-dashoffset: 0;
  }
}

/* 4 个黄/红粒子从底部上升带横向漂移 */
.plasma-particle-container {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
}

.rising-particle {
  position: absolute;
  bottom: -20px;
  border-radius: 50%;
  pointer-events: none;
}

.particle-p1 {
  left: 15%;
  width: 8px;
  height: 8px;
  background: #FCD34D;
  box-shadow: 0 0 16px #FCD34D, 0 0 30px #EF4444;
  animation: particleRise1 9s ease-in-out infinite;
}

.particle-p2 {
  left: 38%;
  width: 10px;
  height: 10px;
  background: #EF4444;
  box-shadow: 0 0 20px #EF4444, 0 0 35px #FCD34D;
  animation: particleRise2 11s ease-in-out infinite 2s;
}

.particle-p3 {
  left: 68%;
  width: 6px;
  height: 6px;
  background: #FCD34D;
  box-shadow: 0 0 14px #FCD34D;
  animation: particleRise3 10s ease-in-out infinite 4s;
}

.particle-p4 {
  left: 88%;
  width: 9px;
  height: 9px;
  background: #EF4444;
  box-shadow: 0 0 18px #EF4444;
  animation: particleRise4 12s ease-in-out infinite 1.5s;
}

@keyframes particleRise1 {
  0% { transform: translateY(0) translateX(0); opacity: 0; }
  15% { opacity: 0.85; }
  50% { transform: translateY(-50vh) translateX(45px); opacity: 1; }
  85% { opacity: 0.8; }
  100% { transform: translateY(-105vh) translateX(-35px); opacity: 0; }
}

@keyframes particleRise2 {
  0% { transform: translateY(0) translateX(0); opacity: 0; }
  15% { opacity: 0.9; }
  50% { transform: translateY(-50vh) translateX(-50px); opacity: 0.95; }
  85% { opacity: 0.75; }
  100% { transform: translateY(-105vh) translateX(40px); opacity: 0; }
}

@keyframes particleRise3 {
  0% { transform: translateY(0) translateX(0); opacity: 0; }
  20% { opacity: 0.8; }
  50% { transform: translateY(-50vh) translateX(30px); opacity: 0.9; }
  80% { opacity: 0.7; }
  100% { transform: translateY(-105vh) translateX(-25px); opacity: 0; }
}

@keyframes particleRise4 {
  0% { transform: translateY(0) translateX(0); opacity: 0; }
  20% { opacity: 0.85; }
  50% { transform: translateY(-50vh) translateX(-40px); opacity: 1; }
  80% { opacity: 0.75; }
  100% { transform: translateY(-105vh) translateX(30px); opacity: 0; }
}

/* ==========================================================================
   页面容器与页眉导航
   ========================================================================== */

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(2, 6, 23, 0.88);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--border-color);
  height: 74px;
  display: flex;
  align-items: center;
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-headline);
  font-size: 1.4rem;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: #fff;
}

.brand-logo .cat-icon {
  font-size: 1.8rem;
  filter: drop-shadow(0 0 10px #FCD34D);
}

.brand-name-en {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary-accent);
  margin-left: 4px;
  text-shadow: 0 0 10px rgba(252, 211, 77, 0.5);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  color: rgba(255, 255, 255, 0.85);
  font-size: 0.95rem;
  font-weight: 600;
}

.nav-links a:hover {
  color: var(--primary-accent);
  text-shadow: 0 0 10px rgba(252, 211, 77, 0.6);
}

.nav-action {
  display: flex;
  align-items: center;
  gap: 14px;
}

/* ==========================================================================
   【CTA 按钮】
   黄到红渐变（文字黑色），圆角 8px，带 30px 黄色辉光，hover 时辉光变红
   满足移动端触摸目标 >= 44×44 CSS 像素
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 26px;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-btn); /* 8px 圆角 */
  cursor: pointer;
  border: none;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  text-align: center;
  white-space: nowrap;
  font-family: var(--font-body);
  min-height: 44px; /* 触控目标不小于 44px */
  min-width: 44px;
}

.btn-primary {
  background: var(--gradient-plasma); /* 黄到红渐变 */
  color: #000000; /* 文字黑色 */
  box-shadow: 0 0 30px rgba(252, 211, 77, 0.5); /* 30px 黄色辉光 */
}

.btn-primary:hover {
  background: var(--gradient-plasma);
  color: #000000;
  transform: translateY(-2px);
  box-shadow: 0 0 35px rgba(239, 68, 68, 0.85); /* hover 时辉光变红 */
}

.btn-secondary {
  background: rgba(15, 23, 42, 0.85);
  color: #FFFFFF;
  border: 1px solid rgba(252, 211, 77, 0.3);
  box-shadow: 0 0 15px rgba(252, 211, 77, 0.15);
}

.btn-secondary:hover {
  background: rgba(30, 41, 59, 0.95);
  border-color: var(--primary-accent);
  color: var(--primary-accent);
  box-shadow: 0 0 25px rgba(252, 211, 77, 0.4);
  transform: translateY(-2px);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.1rem;
  min-height: 52px;
}

.btn-sm {
  padding: 10px 20px;
  font-size: 0.9rem;
  min-height: 44px; /* 满足 44px 标准 */
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   【主视觉区 (Hero Section)】
   ========================================================================== */

.hero {
  padding: 85px 0 65px;
  position: relative;
}

.hero-layout {
  display: grid;
  grid-template-columns: 1.25fr 0.95fr;
  align-items: center;
  gap: 40px;
}

.hero-left {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border-radius: var(--radius-pill);
  background: rgba(252, 211, 77, 0.1);
  border: 1px solid rgba(252, 211, 77, 0.35);
  color: var(--primary-accent);
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 24px;
  box-shadow: 0 0 15px rgba(252, 211, 77, 0.2);
}

/* 大标题：800 字重，黄到红渐变 + 双层文字阴影 */
.hero-title {
  font-family: var(--font-headline);
  font-weight: 800;
  font-size: 3.4rem;
  line-height: 1.15;
  margin-bottom: 22px;
  letter-spacing: -0.02em;
  background: var(--gradient-plasma);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  filter: drop-shadow(0 0 20px rgba(252, 211, 77, 0.65)) 
          drop-shadow(0 0 45px rgba(239, 68, 68, 0.5));
}

.hero-title .title-sub {
  display: block;
  font-size: 2.1rem;
  font-weight: 800;
  margin-top: 8px;
  color: #FFFFFF;
  -webkit-text-fill-color: #FFFFFF;
  filter: none;
  text-shadow: 0 0 15px rgba(255, 255, 255, 0.4);
}

.hero-subtitle {
  font-family: var(--font-body);
  font-size: 1.08rem;
  color: var(--text-muted);
  max-width: 660px;
  margin-bottom: 34px;
  line-height: 1.75;
}

.hero-subtitle strong {
  color: var(--primary-accent);
}

.hero-cta {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  width: 100%;
  padding-top: 26px;
  border-top: 1px solid var(--border-color);
}

.stat-item .stat-num {
  display: block;
  font-family: var(--font-headline);
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--primary-accent);
  text-shadow: 0 0 12px rgba(252, 211, 77, 0.4);
  margin-bottom: 4px;
}

.stat-item p {
  font-size: 0.85rem;
  color: var(--text-dim);
}

/* ==========================================================================
   右侧太阳科技日冕喷发动画 (Solar Core + Coronal Jets + Orbits + Wind Particles)
   ========================================================================== */

.solar-system-wrap {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  width: 100%;
  min-height: 380px;
}

.solar-stage {
  position: relative;
  width: 340px;
  height: 340px;
  display: flex;
  justify-content: center;
  align-items: center;
}

/* 160×160px 太阳核心 (白→黄→红径向渐变, blur+脉冲呼吸3s, 双层box-shadow辉光) */
.solar-core {
  position: absolute;
  width: 160px;
  height: 160px;
  border-radius: 50%;
  background: radial-gradient(circle, #FFFFFF 0%, #FCD34D 42%, #EF4444 88%, rgba(239, 68, 68, 0.4) 100%);
  box-shadow: 0 0 50px rgba(252, 211, 77, 0.9), 
              0 0 100px rgba(239, 68, 68, 0.7);
  filter: blur(1.5px);
  z-index: 10;
  animation: solarPulse 3s ease-in-out infinite;
}

@keyframes solarPulse {
  0%, 100% {
    transform: scale(1);
    box-shadow: 0 0 45px rgba(252, 211, 77, 0.85), 
                0 0 90px rgba(239, 68, 68, 0.65);
  }
  50% {
    transform: scale(1.08);
    box-shadow: 0 0 65px rgba(252, 211, 77, 1), 
                0 0 130px rgba(239, 68, 68, 0.9);
  }
}

/* 8 条 8×100px 日冕喷流 */
.coronal-jets-container {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  pointer-events: none;
  z-index: 5;
}

.coronal-jet {
  position: absolute;
  width: 8px;
  height: 100px;
  border-radius: 4px;
  transform-origin: center 170px;
  top: calc(50% - 170px);
  left: calc(50% - 4px);
  animation: jetPulse 1.5s ease-in-out infinite alternate;
}

.jet-1 { transform: rotate(0deg); background: linear-gradient(to top, rgba(252, 211, 77, 0.95), transparent); animation-delay: 0s; }
.jet-2 { transform: rotate(45deg); background: linear-gradient(to top, rgba(239, 68, 68, 0.95), transparent); animation-delay: 0.18s; }
.jet-3 { transform: rotate(90deg); background: linear-gradient(to top, rgba(252, 211, 77, 0.95), transparent); animation-delay: 0.36s; }
.jet-4 { transform: rotate(135deg); background: linear-gradient(to top, rgba(239, 68, 68, 0.95), transparent); animation-delay: 0.54s; }
.jet-5 { transform: rotate(180deg); background: linear-gradient(to top, rgba(252, 211, 77, 0.95), transparent); animation-delay: 0.72s; }
.jet-6 { transform: rotate(225deg); background: linear-gradient(to top, rgba(239, 68, 68, 0.95), transparent); animation-delay: 0.90s; }
.jet-7 { transform: rotate(270deg); background: linear-gradient(to top, rgba(252, 211, 77, 0.95), transparent); animation-delay: 1.08s; }
.jet-8 { transform: rotate(315deg); background: linear-gradient(to top, rgba(239, 68, 68, 0.95), transparent); animation-delay: 1.26s; }

@keyframes jetPulse {
  0% { transform: rotate(var(--angle, 0deg)) scaleY(0.75); opacity: 0.6; }
  100% { transform: rotate(var(--angle, 0deg)) scaleY(1.35); opacity: 1; }
}

/* 2 层反向旋转虚线轨道 */
.dashed-orbit-1 {
  position: absolute;
  width: 250px;
  height: 250px;
  border-radius: 50%;
  border: 2px dashed rgba(252, 211, 77, 0.5);
  box-shadow: 0 0 20px rgba(252, 211, 77, 0.2);
  z-index: 6;
  animation: orbitRotateCW 22s linear infinite;
}

.dashed-orbit-2 {
  position: absolute;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  border: 2px dashed rgba(239, 68, 68, 0.5);
  box-shadow: 0 0 20px rgba(239, 68, 68, 0.2);
  z-index: 6;
  animation: orbitRotateCCW 28s linear infinite;
}

@keyframes orbitRotateCW { from { transform: rotate(0deg); } to { transform: rotate(360deg); } }
@keyframes orbitRotateCCW { from { transform: rotate(0deg); } to { transform: rotate(-360deg); } }

/* 3 个太阳风公转粒子 */
.solar-wind-track {
  position: absolute;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  z-index: 8;
  pointer-events: none;
  animation: windOrbit 6s linear infinite;
}

.wind-particle {
  position: absolute;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  top: -5px;
  left: calc(50% - 5px);
}

.wind-particle-1 { background: #FCD34D; box-shadow: 0 0 15px #FCD34D, 0 0 25px #EF4444; }
.wind-particle-2 { background: #EF4444; box-shadow: 0 0 15px #EF4444, 0 0 25px #FCD34D; top: auto; bottom: -5px; left: calc(50% - 5px); }
.wind-particle-3 { background: #FFFFFF; box-shadow: 0 0 15px #FFFFFF, 0 0 25px #FCD34D; top: calc(50% - 5px); left: -5px; }

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

/* ==========================================================================
   各内容模块通用样式
   ========================================================================== */

.section {
  padding: 85px 0;
  position: relative;
  z-index: 1;
}

.section-head {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 52px;
}

.section-tag {
  color: var(--primary-accent);
  font-family: var(--font-headline);
  font-weight: 800;
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  margin-bottom: 10px;
  display: block;
  text-shadow: 0 0 10px rgba(252, 211, 77, 0.4);
}

.section-title {
  font-family: var(--font-headline);
  font-size: 2.3rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 14px;
  letter-spacing: -0.02em;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-dim);
}

/* 核心优势卡片 (3 Cards) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 36px 30px;
  transition: all 0.35s ease;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-plasma);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-6px);
  border-color: var(--border-glow);
  box-shadow: var(--shadow-card), 0 0 25px rgba(239, 68, 68, 0.35);
  background: var(--bg-card-hover);
}

.feature-card:hover::before {
  opacity: 1;
}

.feature-icon-wrap {
  width: 58px;
  height: 58px;
  border-radius: 12px;
  background: rgba(252, 211, 77, 0.12);
  border: 1px solid rgba(252, 211, 77, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  color: var(--primary-accent);
  box-shadow: 0 0 15px rgba(252, 211, 77, 0.2);
}

.feature-card h3 {
  font-family: var(--font-headline);
  font-size: 1.28rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--text-dim);
  font-size: 0.95rem;
  line-height: 1.65;
  margin-bottom: 20px;
  flex-grow: 1;
}

.feature-list {
  list-style: none;
  border-top: 1px solid var(--border-color);
  padding-top: 18px;
}

.feature-list li {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.feature-list li::before {
  content: "✔";
  color: var(--primary-accent);
  font-weight: bold;
}

/* 流媒体与 AI 支持图卡 */
.media-ai-container {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.support-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 36px;
  display: flex;
  flex-direction: column;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-card);
}

.support-panel:hover {
  border-color: var(--border-glow);
  box-shadow: var(--shadow-card), 0 0 25px rgba(252, 211, 77, 0.25);
}

.panel-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 16px;
}

.panel-icon {
  font-size: 2.2rem;
  filter: drop-shadow(0 0 10px #FCD34D);
}

.panel-header h3 {
  font-family: var(--font-headline);
  font-size: 1.35rem;
  font-weight: 800;
  color: #fff;
}

.support-panel > p {
  color: var(--text-dim);
  font-size: 0.95rem;
  margin-bottom: 24px;
}

.tags-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 12px;
  margin-top: auto;
}

.tag-item {
  background: rgba(2, 6, 23, 0.7);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-btn);
  padding: 10px 14px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.88rem;
  font-weight: 600;
  color: #fff;
  transition: all 0.25s ease;
}

.tag-item:hover {
  background: rgba(252, 211, 77, 0.12);
  border-color: var(--primary-accent);
  box-shadow: 0 0 12px rgba(252, 211, 77, 0.3);
}

.tag-badge {
  display: inline-block;
  font-size: 0.72rem;
  background: rgba(239, 68, 68, 0.2);
  color: #F87171;
  border: 1px solid rgba(239, 68, 68, 0.35);
  padding: 2px 6px;
  border-radius: 4px;
  margin-left: auto;
}

/* ==========================================================================
   套餐对比区域 (语义化表格与无缝卡片结构，支持水平滚动)
   ========================================================================== */

.pricing-table-container {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  padding: 10px 0;
}

.pricing-table-container:focus-visible {
  outline: 2px dashed var(--primary-accent);
  border-radius: var(--radius-card);
}

.pricing-semantic-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 24px 0;
}

.pricing-semantic-table caption {
  margin-bottom: 16px;
  font-size: 0.9rem;
  color: var(--text-dim);
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 38px 28px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all 0.35s ease;
  box-shadow: var(--shadow-card);
}

.pricing-card.popular {
  border-color: var(--primary-accent);
  background: rgba(15, 23, 42, 0.92);
  box-shadow: 0 0 35px rgba(252, 211, 77, 0.3);
  transform: scale(1.03);
}

.pricing-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--gradient-plasma);
  color: #000;
  font-family: var(--font-headline);
  font-size: 0.8rem;
  font-weight: 800;
  padding: 4px 16px;
  border-radius: var(--radius-pill);
  box-shadow: 0 0 15px rgba(252, 211, 77, 0.6);
}

.pricing-card h3 {
  font-family: var(--font-headline);
  font-size: 1.35rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 8px;
}

.plan-desc {
  font-size: 0.88rem;
  color: var(--text-dim);
  margin-bottom: 24px;
  min-height: 42px;
}

.pricing-price {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin-bottom: 24px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-color);
}

.currency {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--primary-accent);
}

.amount {
  font-family: var(--font-headline);
  font-size: 2.8rem;
  font-weight: 900;
  color: #fff;
  line-height: 1;
  text-shadow: 0 0 15px rgba(255, 255, 255, 0.3);
}

.period {
  color: var(--text-dim);
  font-size: 0.9rem;
}

.plan-features {
  list-style: none;
  margin-bottom: 32px;
  flex-grow: 1;
}

.plan-features li {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.plan-features li svg {
  flex-shrink: 0;
  color: var(--primary-accent);
  filter: drop-shadow(0 0 5px #FCD34D);
}

/* 用户评价 (Testimonials) */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 28px;
  display: flex;
  flex-direction: column;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-card);
}

.testimonial-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-4px);
  box-shadow: var(--shadow-card), 0 0 20px rgba(239, 68, 68, 0.25);
}

.review-stars {
  color: var(--primary-accent);
  text-shadow: 0 0 10px rgba(252, 211, 77, 0.6);
  margin-bottom: 14px;
  font-size: 1.1rem;
  letter-spacing: 2px;
}

.review-content {
  color: var(--text-muted);
  font-size: 0.94rem;
  line-height: 1.65;
  margin-bottom: 20px;
  flex-grow: 1;
  font-style: italic;
}

.reviewer-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  border-top: 1px solid var(--border-color);
  padding-top: 16px;
}

.reviewer-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--gradient-plasma);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: #000;
  font-size: 1rem;
  box-shadow: 0 0 12px rgba(252, 211, 77, 0.5);
}

.reviewer-info h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
}

.reviewer-info p {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* 常见问题解答 (FAQ) */
.faq-grid {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  overflow: hidden;
  transition: border-color 0.25s ease;
  box-shadow: var(--shadow-card);
}

.faq-item:hover {
  border-color: rgba(252, 211, 77, 0.4);
}

.faq-item summary {
  padding: 20px 24px;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 1.05rem;
  font-weight: 600;
  color: #fff;
  user-select: none;
}

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

.faq-arrow {
  color: var(--primary-accent);
  transition: transform 0.3s ease;
  font-size: 1.3rem;
  display: inline-block;
}

.faq-item[open] .faq-arrow {
  transform: rotate(45deg);
  color: var(--secondary-accent);
}

.faq-item[open] summary {
  border-bottom: 1px solid var(--border-color);
}

.faq-answer {
  padding: 20px 24px;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* 底部 CTA 引导横幅 */
.cta-banner {
  margin: 80px 0 40px;
  background: radial-gradient(circle at 50% 50%, rgba(239, 68, 68, 0.22) 0%, rgba(15, 23, 42, 0.95) 75%);
  border: 1px solid rgba(252, 211, 77, 0.35);
  border-radius: var(--radius-card);
  padding: 56px 32px;
  text-align: center;
  box-shadow: 0 10px 40px -10px rgba(0, 0, 0, 0.8), 0 0 35px rgba(252, 211, 77, 0.2);
}

.cta-banner h2 {
  font-family: var(--font-headline);
  font-size: 2.2rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 14px;
}

.cta-banner p {
  color: var(--text-dim);
  font-size: 1.1rem;
  max-width: 620px;
  margin: 0 auto 30px;
}

/* 页脚 (Footer) - 保持严格4个标题并新页面打开，增强文字对比度至 4.5:1 以上 */
.site-footer {
  border-top: 1px solid var(--border-color);
  background: #01030b;
  padding: 48px 0 36px;
  margin-top: 40px;
  position: relative;
  z-index: 1;
}

.footer-nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 48px;
  margin-bottom: 28px;
  list-style: none;
  flex-wrap: wrap;
}

.footer-nav a {
  color: var(--text-dim);
  font-size: 1.05rem;
  font-weight: 600;
  position: relative;
  padding-bottom: 4px;
}

.footer-nav a:hover {
  color: var(--primary-accent);
  text-shadow: 0 0 10px rgba(252, 211, 77, 0.5);
}

.footer-nav a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--gradient-plasma);
  transition: width 0.25s ease;
}

.footer-nav a:hover::after {
  width: 100%;
}

.footer-copy {
  text-align: center;
  color: rgba(255, 255, 255, 0.65); /* 强化对比度超 4.5:1 */
  font-size: 0.88rem;
}

/* 次级页面样式 */
.page-header {
  padding: 70px 0 40px;
  text-align: center;
  border-bottom: 1px solid var(--border-color);
  background: radial-gradient(circle at 50% 0%, rgba(252, 211, 77, 0.12) 0%, transparent 70%);
  position: relative;
  z-index: 1;
}

.page-title {
  font-family: var(--font-headline);
  font-size: 2.6rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 12px;
  background: var(--gradient-plasma);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  filter: drop-shadow(0 0 15px rgba(252, 211, 77, 0.4));
}

.page-subtitle {
  color: var(--text-dim);
  font-size: 1.05rem;
  max-width: 620px;
  margin: 0 auto;
}

.doc-content {
  max-width: 860px;
  margin: 50px auto 80px;
  padding: 40px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  position: relative;
  z-index: 1;
}

.doc-section {
  margin-bottom: 38px;
}

.doc-section:last-child {
  margin-bottom: 0;
}

.doc-section h2 {
  font-family: var(--font-headline);
  font-size: 1.35rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
  border-bottom: 1px solid rgba(252, 211, 77, 0.12);
  padding-bottom: 8px;
}

.doc-section p {
  color: var(--text-muted);
  font-size: 0.98rem;
  line-height: 1.75;
  margin-bottom: 12px;
}

.doc-section ul {
  list-style-type: none;
  margin-bottom: 14px;
}

.doc-section ul li {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
  margin-bottom: 8px;
  padding-left: 20px;
  position: relative;
}

.doc-section ul li::before {
  content: "•";
  color: var(--primary-accent);
  position: absolute;
  left: 6px;
  font-size: 1.2rem;
}

.back-home-wrap {
  text-align: center;
  margin-top: 40px;
}

/* 网站地图卡片网格 */
.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.sitemap-card {
  background: rgba(2, 6, 23, 0.6);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 24px;
}

.sitemap-card h3 {
  font-family: var(--font-headline);
  font-size: 1.15rem;
  color: var(--primary-accent);
  margin-bottom: 16px;
  font-weight: 800;
}

.sitemap-card ul {
  list-style: none;
}

.sitemap-card li {
  margin-bottom: 10px;
}

.sitemap-card a {
  color: var(--text-muted);
  font-size: 0.95rem;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.sitemap-card a:hover {
  color: var(--primary-accent);
  padding-left: 4px;
}

/* 知识科普专栏样式 */
.article-quick-nav {
  margin-bottom: 50px;
  background: rgba(2, 6, 23, 0.7);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 30px;
  box-shadow: var(--shadow-card);
}

.article-quick-nav h2 {
  font-family: var(--font-headline);
  font-size: 1.3rem;
  color: var(--primary-accent);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.quick-nav-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.quick-nav-item {
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(252, 211, 77, 0.15);
  border-radius: var(--radius-btn);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: all 0.25s ease;
}

.quick-nav-item:hover {
  border-color: var(--primary-accent);
  background: rgba(30, 41, 59, 0.95);
  transform: translateY(-3px);
  box-shadow: 0 0 15px rgba(252, 211, 77, 0.25);
}

.quick-nav-item .nav-badge {
  font-size: 0.75rem;
  color: var(--primary-accent);
  font-weight: 700;
}

.quick-nav-item .nav-title {
  font-size: 0.92rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.45;
}

.seo-article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-card);
  padding: 38px 34px;
  margin-bottom: 48px;
  box-shadow: var(--shadow-card);
  position: relative;
  transition: border-color 0.3s ease;
}

.seo-article-card:hover {
  border-color: rgba(252, 211, 77, 0.35);
}

.seo-article-header {
  margin-bottom: 24px;
  border-bottom: 1px solid rgba(252, 211, 77, 0.15);
  padding-bottom: 20px;
}

.article-tags-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

.article-cat-tag {
  background: rgba(239, 68, 68, 0.2);
  color: #F87171;
  border: 1px solid rgba(239, 68, 68, 0.35);
  font-size: 0.76rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 4px;
}

.article-word-count {
  font-size: 0.78rem;
  color: var(--text-dim);
}

.seo-article-title {
  font-family: var(--font-headline);
  font-size: 1.6rem;
  font-weight: 800;
  color: #fff;
  line-height: 1.35;
  margin-bottom: 12px;
}

.seo-article-title a {
  color: #fff;
}

.seo-article-title a:hover {
  color: var(--primary-accent);
}

.article-summary-box {
  background: rgba(2, 6, 23, 0.6);
  border-left: 3px solid var(--primary-accent);
  padding: 14px 18px;
  border-radius: 0 var(--radius-btn) var(--radius-btn) 0;
  margin-bottom: 24px;
  color: var(--text-muted);
  font-size: 0.94rem;
  line-height: 1.65;
}

.article-body-content h3 {
  font-family: var(--font-headline);
  font-size: 1.22rem;
  font-weight: 800;
  color: var(--primary-accent);
  margin: 24px 0 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.article-body-content p {
  color: var(--text-muted);
  font-size: 0.98rem;
  line-height: 1.8;
  margin-bottom: 16px;
  text-align: justify;
}

.article-body-content ul {
  list-style: none;
  margin-bottom: 20px;
}

.article-body-content ul li {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.75;
  margin-bottom: 10px;
  padding-left: 22px;
  position: relative;
}

.article-body-content ul li::before {
  content: "⚡";
  color: var(--primary-accent);
  position: absolute;
  left: 2px;
  font-size: 0.9rem;
}

.article-internal-link {
  color: var(--primary-accent);
  font-weight: 700;
  text-decoration: underline;
  text-underline-offset: 4px;
  transition: color 0.2s ease;
}

.article-internal-link:hover {
  color: #ffffff;
  text-shadow: 0 0 10px rgba(252, 211, 77, 0.6);
}

.article-faq-wrap {
  margin-top: 26px;
  padding-top: 22px;
  border-top: 1px dashed rgba(252, 211, 77, 0.25);
}

.article-faq-title {
  font-family: var(--font-headline);
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--primary-accent);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.article-faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.article-faq-item {
  background: rgba(2, 6, 23, 0.65);
  border: 1px solid rgba(252, 211, 77, 0.2);
  border-radius: var(--radius-btn);
  overflow: hidden;
  transition: border-color 0.25s ease;
}

.article-faq-item:hover {
  border-color: rgba(252, 211, 77, 0.45);
}

.article-faq-item summary {
  padding: 12px 18px;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
  user-select: none;
  background: rgba(15, 23, 42, 0.5);
}

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

.article-faq-item[open] summary {
  border-bottom: 1px solid rgba(252, 211, 77, 0.15);
  color: var(--primary-accent);
}

.article-faq-item .faq-arrow {
  color: var(--primary-accent);
  transition: transform 0.25s ease;
  font-size: 1.1rem;
}

.article-faq-item[open] .faq-arrow {
  transform: rotate(45deg);
  color: var(--secondary-accent);
}

.article-faq-answer {
  padding: 14px 18px;
  color: var(--text-muted);
  font-size: 0.92rem;
  line-height: 1.7;
}

.article-bottom-cta {
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px dashed rgba(252, 211, 77, 0.2);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.article-bottom-cta .cta-tip {
  font-size: 0.92rem;
  color: var(--text-dim);
}

/* ==========================================================================
   无障碍：遵循 prefers-reduced-motion
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

/* ==========================================================================
   响应式媒体查询 (@media)
   ========================================================================== */

@media (max-width: 992px) {
  .hero-layout {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .hero-left {
    align-items: center;
    text-align: center;
  }
  .hero-title {
    font-size: 2.8rem;
  }
  .features-grid,
  .pricing-grid,
  .testimonials-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-card.popular {
    transform: none;
  }
  .quick-nav-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .navbar {
    height: 64px;
  }
  .nav-links {
    display: none;
  }
  .hero {
    padding: 50px 0 35px;
  }
  .hero-title {
    font-size: 2.1rem;
  }
  .hero-title .title-sub {
    font-size: 1.5rem;
  }
  .hero-subtitle {
    font-size: 1rem;
  }
  .hero-stats {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .stat-item {
    padding: 10px 0;
    border-bottom: 1px solid rgba(252, 211, 77, 0.1);
  }
  .stat-item:last-child {
    border-bottom: none;
  }
  .section {
    padding: 55px 0;
  }
  .section-title {
    font-size: 1.75rem;
  }
  .features-grid,
  .media-ai-container,
  .pricing-grid,
  .testimonials-grid,
  .sitemap-grid,
  .quick-nav-grid {
    grid-template-columns: 1fr;
  }
  .solar-stage {
    width: 280px;
    height: 280px;
    transform: scale(0.85);
  }
  .footer-nav {
    flex-direction: column;
    gap: 18px;
  }
  .doc-content,
  .seo-article-card {
    padding: 24px 18px;
    margin: 30px auto 60px;
  }
  .seo-article-title {
    font-size: 1.35rem;
  }
  .btn {
    min-height: 48px;
    padding: 12px 24px;
  }
  .hero-cta,
  .article-bottom-cta {
    flex-direction: column;
    width: 100%;
  }
  .hero-cta .btn,
  .article-bottom-cta .btn {
    width: 100%;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }
  .hero-title {
    font-size: 1.75rem;
  }
  .hero-title .title-sub {
    font-size: 1.3rem;
  }
  .pricing-card {
    padding: 30px 20px;
  }
  .amount {
    font-size: 2.4rem;
  }
}