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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.7;
  letter-spacing: 0.01em;
  background-color: #0B1026;
  color: #F8FAFC;
  min-height: 100vh;
  overflow-x: hidden;
  transition: background-color 0.4s ease;
}

body.nav-open {
  overflow: hidden;
}

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

ul, ol {
  list-style: none;
}

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

button {
  font: inherit;
  border: none;
  background: none;
  color: inherit;
  cursor: pointer;
}

input, textarea, select {
  font: inherit;
}

table {
  border-collapse: collapse;
  width: 100%;
}

:focus-visible {
  outline: 2px solid #F4B63D;
  outline-offset: 4px;
  border-radius: 4px;
}

::selection {
  background-color: rgba(244, 182, 61, 0.3);
  color: #F8FAFC;
}

/* ============ CSS 自定义属性 ============ */
:root {
  --color-space: #0B1026;
  --color-space-light: #131A38;
  --color-space-deep: #060913;
  --color-paper: #F4EEDD;
  --color-paper-dark: #E9DFC8;
  --color-paper-light: #FBF7ED;
  --color-gold: #F4B63D;
  --color-gold-bright: #FFC866;
  --color-gold-dim: rgba(244, 182, 61, 0.25);
  --color-purple: #8B5CF6;
  --color-purple-light: #A78BFA;
  --color-purple-dim: rgba(139, 92, 246, 0.18);
  --color-ink: #202020;
  --color-moon: #F8FAFC;
  --color-teal: #14B8A6;
  --color-orange: #F97316;
  --color-gray-100: #F3F4F6;
  --color-gray-200: #E5E7EB;
  --color-gray-400: #9CA3AF;
  --color-gray-600: #4B5563;

  --font-body: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-heading: "Noto Sans SC", "DIN Alternate", sans-serif;

  --header-height: 72px;
  --container-width: 1200px;
  --container-padding: 24px;
  --radius: 18px;
  --radius-sm: 10px;
  --transition: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* ============ 跳转链接 ============ */
.skip-link {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 2000;
  padding: 0.6rem 1.2rem;
  background: var(--color-gold);
  color: var(--color-ink);
  font-weight: 700;
  font-size: 0.875rem;
  border-radius: 0 0 12px 0;
  transform: translateY(-120%);
  transition: transform 0.2s ease;
}

.skip-link:focus-visible {
  transform: translateY(0);
  outline: none;
}

/* ============ 滚动进度条 ============ */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  z-index: 1500;
  background: transparent;
  pointer-events: none;
}

.scroll-progress span {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--color-gold), var(--color-purple));
  box-shadow: 0 0 10px rgba(244, 182, 61, 0.5);
  border-radius: 0 4px 4px 0;
}

/* ============ 头部区域 ============ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 0;
  transition: background 0.4s ease, box-shadow 0.4s ease, border-color 0.4s ease;
  border-bottom: 1px solid rgba(248, 250, 252, 0);
  background: transparent;
}

/* 滚动后状态当 body 有这个 class */
body.header-scrolled .site-header {
  background: linear-gradient(180deg, rgba(11, 16, 38, 0.96), rgba(11, 16, 38, 0.88));
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border-bottom-color: rgba(139, 92, 246, 0.2);
  box-shadow: 0 8px 34px rgba(0, 0, 0, 0.4);
}

.nav-orbit-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  opacity: 0.25;
}

.orbit-ring {
  position: absolute;
  border-radius: 50%;
  border: 1px solid rgba(244, 182, 61, 0.35);
  width: 340px;
  height: 340px;
  right: 4%;
  top: -240px;
}

.orbit-ring-1 {
  width: 340px;
  height: 340px;
}

.orbit-ring-2 {
  width: 470px;
  height: 470px;
  right: 8%;
  top: -320px;
  border-color: rgba(139, 92, 246, 0.3);
  animation: spinSlow 40s linear infinite;
}

.orbit-ring-3 {
  width: 600px;
  height: 600px;
  right: 12%;
  top: -420px;
  border-color: rgba(20, 184, 166, 0.2);
  animation: spinSlow 60s linear infinite reverse;
}

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

.header-inner {
  position: relative;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
  height: var(--header-height);
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

/* 品牌 */
.site-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
  color: var(--color-moon);
  text-decoration: none;
}

.brand-orbit {
  position: relative;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.orbit-core {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, var(--color-gold-bright), var(--color-gold) 55%, #B8860B);
  box-shadow: 0 0 18px rgba(244, 182, 61, 0.7);
  position: relative;
  z-index: 2;
}

.orbit-dot {
  position: absolute;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-purple-light);
  box-shadow: 0 0 10px rgba(139, 92, 246, 0.8);
  animation: orbitMove 8s linear infinite;
  left: 50%;
  top: 50%;
  transform-origin: 0 0;
}

@keyframes orbitMove {
  from { transform: rotate(0deg) translateX(28px); }
  to { transform: rotate(360deg) translateX(28px); }
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.6rem;
  letter-spacing: 0.02em;
  color: var(--color-moon);
  text-shadow: 0 0 20px rgba(139, 92, 246, 0.4);
}

.brand-tagline {
  font-size: 0.625rem;
  text-transform: uppercase;
  letter-spacing: 0.3em;
  color: var(--color-gray-400);
}

.header-divider {
  width: 1px;
  height: 28px;
  background: linear-gradient(to bottom, transparent, rgba(244, 182, 61, 0.6), transparent);
  flex-shrink: 0;
}

/* 导航 */
.site-nav {
  margin-left: auto;
}

.site-nav-list {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.site-nav-item {
  position: relative;
}

.site-nav-item::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-purple);
  margin-right: 0.25rem;
  vertical-align: middle;
  opacity: 0.45;
}

.site-nav-item:first-child::before {
  display: none;
}

.nav-link {
  display: inline-block;
  padding: 0.5rem 0.9rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: rgba(248, 250, 252, 0.8);
  border-radius: 8px;
  transition: color 0.25s ease, background 0.25s ease, box-shadow 0.25s ease;
  position: relative;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 20%;
  right: 20%;
  bottom: 2px;
  height: 2px;
  background: linear-gradient(90deg, var(--color-gold), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

.nav-link:hover {
  color: var(--color-moon);
  background: rgba(139, 92, 246, 0.1);
  box-shadow: inset 0 0 0 1px rgba(139, 92, 246, 0.15);
}

.nav-link:hover::after {
  transform: scaleX(1);
}

.nav-link[aria-current="page"] {
  color: var(--color-gold);
  font-weight: 700;
  background: rgba(244, 182, 61, 0.08);
}

.nav-link[aria-current="page"]::before {
  content: "";
  position: absolute;
  top: 50%;
  right: -6px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-gold);
  transform: translateY(-50%);
  box-shadow: 0 0 12px var(--color-gold);
  animation: pulseGold 1.8s infinite;
}

@keyframes pulseGold {
  0%, 100% { box-shadow: 0 0 6px var(--color-gold); }
  50% { box-shadow: 0 0 18px var(--color-gold); }
}

.header-cta {
  flex-shrink: 0;
}

.btn-download {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background: linear-gradient(135deg, var(--color-gold-bright), var(--color-gold) 60%, #D98E04);
  color: var(--color-ink);
  font-weight: 700;
  font-size: 0.875rem;
  padding: 0.55rem 1.35rem;
  border-radius: 999px;
  transition: transform 0.25s ease, box-shadow 0.3s ease;
  box-shadow: 0 4px 20px rgba(244, 182, 61, 0.25);
}

.btn-download:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(244, 182, 61, 0.4);
}

.btn-download-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-space);
  box-shadow: 0 0 8px rgba(11, 16, 38, 0.8);
  animation: pulseGold 2s infinite;
}

/* 通用按钮 */
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, var(--color-gold-bright), var(--color-gold));
  color: var(--color-ink);
  font-weight: 700;
  padding: 0.7rem 1.6rem;
  border-radius: 999px;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  box-shadow: 0 4px 16px rgba(244, 182, 61, 0.25);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(244, 182, 61, 0.4);
}

.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(248, 250, 252, 0.08);
  color: var(--color-moon);
  font-weight: 600;
  padding: 0.7rem 1.6rem;
  border-radius: 999px;
  border: 1px solid rgba(248, 250, 252, 0.2);
  backdrop-filter: blur(8px);
  transition: background 0.25s ease, transform 0.25s ease, border-color 0.25s ease;
}

.btn-ghost:hover {
  background: rgba(248, 250, 252, 0.15);
  border-color: var(--color-gold);
  transform: translateY(-2px);
}

/* 移动端导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 46px;
  height: 46px;
  border-radius: 12px;
  border: 1px solid rgba(248, 250, 252, 0.15);
  background: rgba(11, 16, 38, 0.65);
  backdrop-filter: blur(12px);
  transition: border-color 0.3s, background 0.3s;
  flex-shrink: 0;
}

.nav-toggle:hover {
  border-color: rgba(244, 182, 61, 0.5);
}

.nav-toggle .toggle-icon {
  position: relative;
  width: 24px;
  height: 2px;
  background: var(--color-moon);
  border-radius: 4px;
  transition: background 0.3s;
}

.nav-toggle .toggle-icon::before,
.nav-toggle .toggle-icon::after {
  content: "";
  position: absolute;
  width: 24px;
  height: 2px;
  background: var(--color-moon);
  border-radius: 4px;
  transition: transform 0.35s cubic-bezier(0.68, -0.55, 0.265, 1.55), width 0.3s;
}

.nav-toggle .toggle-icon::before {
  top: -8px;
}

.nav-toggle .toggle-icon::after {
  top: 8px;
}

.nav-toggle[aria-expanded="true"] .toggle-icon {
  background: transparent;
}

.nav-toggle[aria-expanded="true"] .toggle-icon::before {
  top: 0;
  transform: rotate(45deg);
  background: var(--color-gold);
}

.nav-toggle[aria-expanded="true"] .toggle-icon::after {
  top: 0;
  transform: rotate(-45deg);
  background: var(--color-gold);
}

.toggle-icon-label {
  font-size: 0.6rem;
  color: var(--color-gray-400);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* 移动端导航面板 */
.mobile-nav-header {
  display: none;
}

/* 响应式 */
@media (max-width: 1024px) {
  .site-nav {
    position: fixed;
    top: calc(var(--header-height) - 1px);
    right: 0;
    width: min(100%, 380px);
    background: rgba(11, 16, 38, 0.98);
    backdrop-filter: blur(24px);
    border-radius: 0 0 0 24px;
    padding: 1rem 1.5rem 2rem;
    transform: translateX(110%);
    transition: transform 0.4s cubic-bezier(0.22, 1, 0.36, 1);
    border-left: 1px solid rgba(139, 92, 246, 0.2);
    border-bottom: 1px solid rgba(139, 92, 246, 0.2);
    box-shadow: -20px 30px 50px rgba(0, 0, 0, 0.6);
    z-index: 998;
    margin-left: 0;
  }

  .site-nav[data-open="true"] {
    transform: translateX(0);
  }

  .mobile-nav-header {
    display: block;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.3em;
    color: var(--color-gray-400);
    border-bottom: 1px solid rgba(244, 182, 61, 0.2);
    padding-bottom: 0.75rem;
    margin-bottom: 1rem;
  }

  .site-nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0.25rem;
  }

  .site-nav-item {
    margin: 0.2rem 0;
  }

  .site-nav-item::before {
    display: none;
  }

  .nav-link {
    padding: 0.8rem 1rem;
    font-size: 1rem;
    display: block;
    border-radius: 12px;
    border: 1px solid transparent;
  }

  .nav-link:hover {
    border-color: rgba(139, 92, 246, 0.15);
  }

  .header-cta {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
    margin-left: auto;
  }

  .header-inner {
    gap: 0.75rem;
  }

  .site-brand {
    gap: 0.5rem;
  }

  .header-divider {
    display: none;
  }
}

@media (max-width: 640px) {
  :root {
    --header-height: 64px;
    --container-padding: 18px;
  }

  .brand-name {
    font-size: 1.4rem;
  }

  .nav-orbit-bg .orbit-ring {
    width: 280px;
    height: 280px;
    right: -60px;
  }

  .site-nav {
    width: 85%;
  }
}

/* ============ 页脚区域 ============ */
.site-footer {
  position: relative;
  background: linear-gradient(180deg, #060B1A 0%, #0D142F 100%);
  color: var(--color-gray-100);
  margin-top: 0;
  overflow: hidden;
  border-top: 1px solid rgba(139, 92, 246, 0.2);
}

.footer-starfield {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 100%;
  pointer-events: none;
  z-index: 0;
}

.star {
  position: absolute;
  border-radius: 50%;
  background: var(--color-gold);
  animation: twinkle 4s ease-in-out infinite;
}

.star-1 { width: 6px; height: 6px; top: 80px; left: 8%; background: #F8FAFC; }
.star-2 { width: 4px; height: 4px; top: 220px; left: 85%; background: var(--color-gold); animation-delay: 0.5s; }
.star-3 { width: 3px; height: 3px; top: 400px; left: 15%; background: var(--color-purple-light); animation-delay: 1s; }
.star-4 { width: 5px; height: 5px; top: 520px; left: 90%; background: #F8FAFC; animation-delay: 1.5s; }
.star-5 { width: 4px; height: 4px; top: 160px; left: 50%; background: var(--color-teal); animation-delay: 2s; }
.star-6 { width: 8px; height: 8px; top: 700px; left: 70%; background: rgba(244, 182, 61, 0.4); animation-delay: 2.5s; }

@keyframes twinkle {
  0%, 100% { opacity: 0.4; transform: scale(0.8); }
  50% { opacity: 1; transform: scale(1.2); }
}

.footer-radial-glow {
  position: absolute;
  bottom: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.12) 0%, transparent 70%);
  pointer-events: none;
}

.footer-topline {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent 0%, var(--color-gold) 30%, var(--color-purple) 70%, transparent 100%);
  z-index: 1;
}

.footer-inner {
  position: relative;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 3.5rem var(--container-padding) 1.5rem;
  z-index: 2;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 1.1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand-declaration {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.footer-logo {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 2.4rem;
  letter-spacing: 0.02em;
  background: linear-gradient(135deg, var(--color-gold-bright), var(--color-gold) 60%, var(--color-purple-light));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1.2;
  display: inline-block;
}

.footer-desc {
  font-size: 0.875rem;
  color: var(--color-gray-400);
  max-width: 36em;
  line-height: 1.75;
}

.footer-statement {
  margin-top: 0.75rem;
  font-size: 0.8rem;
  color: var(--color-gray-400);
  background: rgba(11, 16, 38, 0.5);
  border-left: 3px solid var(--color-purple);
  padding: 0.85rem 1.1rem;
  border-radius: 0 12px 12px 0;
  line-height: 1.75;
  max-width: 42em;
}

.footer-column-title {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.25em;
  color: var(--color-gold);
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-column-title::before {
  content: "";
  width: 22px;
  height: 3px;
  background: linear-gradient(90deg, var(--color-purple), transparent);
  border-radius: 6px;
}

.footer-nav-links li {
  margin-bottom: 0.6rem;
}

.footer-nav-links a {
  font-size: 0.875rem;
  color: var(--color-gray-200);
  transition: color 0.25s ease, padding-left 0.25s ease;
  position: relative;
  display: inline-block;
  padding: 0.2rem 0;
}

.footer-nav-links a::before {
  content: "";
  position: absolute;
  left: -12px;
  top: 50%;
  width: 6px;
  height: 1px;
  background: var(--color-gold);
  transform: translateY(-50%) scaleX(0);
  transition: transform 0.25s ease;
  transform-origin: left;
}

.footer-nav-links a:hover {
  color: var(--color-gold);
  padding-left: 12px;
}

.footer-nav-links a:hover::before {
  transform: scaleX(1);
}

.footer-contact-flags {
  margin-bottom: 1.5rem;
}

.footer-contact-flags li {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  margin-bottom: 0.6rem;
  font-size: 0.875rem;
  color: var(--color-gray-200);
}

.flag-label {
  flex-shrink: 0;
  min-width: 2.6em;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-gray-400);
  padding-top: 0.15rem;
}

.footer-contact-flags a {
  color: var(--color-gray-200);
  transition: color 0.2s;
}

.footer-contact-flags a:hover {
  color: var(--color-gold);
}

.contact-address {
  color: var(--color-gray-400);
}

.contact-support-note {
  color: var(--color-gray-400);
  font-size: 0.8rem;
}

.footer-legal-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem;
  margin-top: 0.75rem;
}

.footer-legal-links a {
  font-size: 0.8rem;
  color: var(--color-gray-200);
  background: rgba(139, 92, 246, 0.08);
  border: 1px solid rgba(139, 92, 246, 0.1);
  padding: 0.3rem 0.8rem;
  border-radius: 999px;
  transition: background 0.25s, border-color 0.25s, color 0.25s;
}

.footer-legal-links a:hover {
  background: rgba(139, 92, 246, 0.18);
  border-color: var(--color-purple);
  color: var(--color-moon);
}

.legal-divider {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-gold);
  opacity: 0.5;
}

/* 底部栏 */
.footer-bottom-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  border-top: 1px solid rgba(248, 250, 252, 0.08);
  padding-top: 1.25rem;
  margin-top: 0.5rem;
}

.footer-copyright-line,
.footer-icp,
.footer-icp-label,
.footer-global {
  font-size: 0.8rem;
  color: var(--color-gray-400);
}

.footer-icp a {
  color: var(--color-gray-400);
  transition: color 0.2s;
}

.footer-icp a:hover {
  color: var(--color-gold);
}

.footer-icp-label {
  order: 3;
  margin-left: auto;
}

.footer-global {
  order: 4;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  font-size: 0.7rem;
  opacity: 0.4;
}

@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }

  .footer-brand-declaration {
    grid-column: 1 / -1;
  }
}

@media (max-width: 640px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .footer-bottom-bar {
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-icp-label {
    order: 2;
    margin-left: 0;
  }

  .footer-global {
    order: 5;
    margin-top: 0.25rem;
  }
}

/* ============ 返回顶部按钮 ============ */
.back-to-top {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: rgba(11, 16, 38, 0.8);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(244, 182, 61, 0.2);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  z-index: 900;
  transform: translateY(120px);
  opacity: 0;
  transition: transform 0.4s cubic-bezier(0.22, 1, 0.36, 1), opacity 0.4s, border-color 0.2s, box-shadow 0.2s;
  pointer-events: none;
}

.back-to-top.is-visible {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.back-to-top:hover {
  border-color: var(--color-gold);
  box-shadow: 0 0 24px rgba(244, 182, 61, 0.25);
}

.back-to-top-icon {
  font-size: 1rem;
  color: var(--color-gold);
  line-height: 1;
}

.back-to-top-label {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-gray-400);
}

/* ============ 通用容器与网格 ============ */
.page-shell {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* 章节大编号 */
.section-number {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.25rem;
  line-height: 1;
  color: var(--color-gold);
  text-shadow: 0 0 12px rgba(244, 182, 61, 0.4);
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
}

.section-number::before {
  content: "";
  width: 34px;
  height: 2px;
  background: linear-gradient(90deg, var(--color-gold), transparent);
}

/* 玻璃卡片 */
.glass-card {
  background: linear-gradient(145deg, rgba(248, 250, 252, 0.08) 0%, rgba(248, 250, 252, 0.03) 100%);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border: 1px solid rgba(248, 250, 252, 0.1);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.glass-card:hover {
  transform: translateY(-4px);
  border-color: rgba(139, 92, 246, 0.4);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.35);
}

/* ============ 滚动显现动效 ============ */
[data-reveal] {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1), transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
}

[data-reveal][data-reveal-state="visible"] {
  opacity: 1;
  transform: translateY(0);
}

[data-reveal="fade"] {
  transform: none;
}

[data-reveal][data-reveal-state="visible"],
.no-js [data-reveal] {
  opacity: 1;
  transform: none;
}

/* ============ 动效偏好 ============ */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ============ 无 JavaScript 兜底 ============ */
.no-js .site-nav {
  position: static;
  transform: none;
  display: flex;
  background: transparent;
  backdrop-filter: none;
  box-shadow: none;
  border: none;
  margin-left: auto;
}

.no-js .site-nav-list {
  flex-direction: row;
}

.no-js .nav-toggle {
  display: none;
}

.no-js .back-to-top {
  display: none;
}