/* ===== 重置与基础 ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 12px);
  -webkit-text-size-adjust: 100%;
}
body {
  min-height: 100vh;
  background:
    radial-gradient(1200px 600px at 85% -10%, rgba(138, 43, 226, 0.1), transparent 60%),
    radial-gradient(800px 500px at -10% 30%, rgba(255, 215, 0, 0.06), transparent 55%),
    var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
main { display: block; }
#main-content {
  min-height: 60vh;
  outline: none;
}
img, svg, video {
  display: block;
  max-width: 100%;
  height: auto;
}
ul, ol { list-style: none; }
a {
  color: inherit;
  text-decoration: none;
  transition: color var(--ease), border-color var(--ease), background var(--ease), padding-left var(--ease);
}
button {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
  cursor: pointer;
}
h1, h2, h3, h4, h5 {
  font-family: var(--font-head);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: 0.02em;
}
h1 { color: var(--gold); font-size: clamp(2rem, 4.6vw, 3.4rem); }
h2 { color: var(--gold); font-size: clamp(1.5rem, 3vw, 2.2rem); }
h3 { color: var(--text); font-size: 1.25rem; }
::selection {
  background: rgba(255, 215, 0, 0.25);
  color: var(--gold);
}

/* ===== 设计变量 ===== */
:root {
  --bg: #0B0C10;
  --bg-deep: #06070B;
  --bg-elev: #1F2229;
  --bg-elev-2: #14161C;
  --gold: #FFD700;
  --gold-deep: #FFB300;
  --purple: #8A2BE2;
  --purple-deep: #4A0080;
  --orange: #FF6B35;
  --text: #E5E7EB;
  --text-dim: #9CA3AF;
  --danger: #E11D48;
  --line: rgba(255, 215, 0, 0.16);
  --line-violet: rgba(138, 43, 226, 0.32);
  --header-h: 64px;
  --rail-w: 80px;
  --content-max: 1260px;
  --gutter: clamp(16px, 3vw, 40px);
  --radius: 14px;
  --radius-sm: 8px;
  --font-head: 'Noto Serif SC', 'Source Han Serif SC', 'Songti SC', serif;
  --font-body: 'Noto Sans SC', 'Source Han Sans SC', 'PingFang SC', sans-serif;
  --font-data: 'Roboto Mono', 'SFMono-Regular', 'SF Mono', monospace;
  --shadow-card: 0 12px 40px rgba(0, 0, 0, 0.35);
  --glow-gold: 0 0 24px rgba(255, 215, 0, 0.18);
  --glow-violet: 0 0 24px rgba(138, 43, 226, 0.22);
  --ease: 0.32s cubic-bezier(0.2, 0.8, 0.2, 1);
}

/* ===== 布局辅助 ===== */
.container {
  width: 100%;
  max-width: var(--content-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.split {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  align-items: center;
}
@media (min-width: 1024px) {
  .split { grid-template-columns: 1fr 1fr; }
  .split--wide-left { grid-template-columns: 1.1fr 0.9fr; }
  .split--wide-right { grid-template-columns: 0.9fr 1.1fr; }
}

/* ===== 跳过链接 ===== */
.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 2100;
  padding: 10px 18px;
  background: var(--gold);
  color: var(--bg);
  font-weight: 700;
  border-radius: var(--radius-sm);
  transform: translateY(-150%);
  transition: transform var(--ease);
}
.skip-link:focus-visible {
  transform: translateY(0);
}

/* ===== 滚动进度 ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  z-index: 2000;
  background: linear-gradient(90deg, var(--gold), var(--purple), var(--orange));
  box-shadow: 0 0 12px rgba(255, 215, 0, 0.4);
  pointer-events: none;
}

/* ===== 头部 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(11, 12, 16, 0.86);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.site-header::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  background: linear-gradient(90deg, var(--gold), rgba(255, 215, 0, 0.05) 40%, rgba(138, 43, 226, 0.35) 75%, transparent);
  pointer-events: none;
}
.site-header__inner {
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.site-header__meta {
  display: none;
  align-items: center;
  gap: 18px;
  font-family: var(--font-data);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}
.site-header__status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--gold-deep);
}
.site-header__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 8px var(--gold);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.55; transform: scale(0.8); }
}

/* ===== 品牌 ===== */
.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 6px 0;
  position: relative;
}
.site-brand__staff {
  position: relative;
  flex: 0 0 10px;
  width: 10px;
  height: 34px;
  background: linear-gradient(180deg, var(--gold), var(--orange));
  border-radius: 3px;
  box-shadow: var(--glow-gold);
}
.site-brand__staff::before,
.site-brand__staff::after {
  content: '';
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 18px;
  height: 6px;
  border-radius: 3px;
}
.site-brand__staff::before {
  top: -3px;
  background: var(--gold);
}
.site-brand__staff::after {
  bottom: -3px;
  background: var(--orange);
}
.site-brand__name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.25rem;
  letter-spacing: 0.08em;
  color: var(--text);
}
.site-brand__tag {
  font-family: var(--font-data);
  font-size: 0.68rem;
  color: var(--gold);
  letter-spacing: 0.18em;
  border-left: 1px solid var(--line);
  padding-left: 10px;
  white-space: nowrap;
}
.site-brand--footer .site-brand__staff {
  height: 28px;
  flex-basis: 9px;
  width: 9px;
}
.site-brand--footer .site-brand__staff::before,
.site-brand--footer .site-brand__staff::after {
  width: 15px;
  height: 5px;
}
.site-brand--footer .site-brand__name {
  color: var(--gold);
  font-size: 1.15rem;
}

/* ===== 移动菜单按钮 ===== */
.site-nav-toggle {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 11px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--bg-elev);
  transition: border-color var(--ease), box-shadow var(--ease);
}
.site-nav-toggle:hover {
  border-color: var(--gold);
  box-shadow: var(--glow-gold);
}
.site-nav-toggle__bar {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--gold);
  border-radius: 2px;
  transition: transform var(--ease), opacity var(--ease);
}
.site-nav-toggle[aria-expanded="true"] .site-nav-toggle__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.site-nav-toggle[aria-expanded="true"] .site-nav-toggle__bar:nth-child(2) {
  opacity: 0;
}
.site-nav-toggle[aria-expanded="true"] .site-nav-toggle__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ===== 移动端全屏导航 ===== */
.site-nav {
  position: fixed;
  inset: 0;
  z-index: 990;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 40px;
  padding: calc(var(--header-h) + 24px) 24px 48px;
  background:
    radial-gradient(600px 400px at 80% 10%, rgba(138, 43, 226, 0.18), transparent 60%),
    radial-gradient(500px 300px at 10% 80%, rgba(255, 215, 0, 0.08), transparent 60%),
    rgba(6, 7, 11, 0.97);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity var(--ease), visibility var(--ease);
}
.site-nav[data-open="true"] {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}
.site-nav__list {
  display: grid;
  gap: 6px;
  width: 100%;
  max-width: 380px;
}
.site-nav__link {
  display: block;
  text-align: center;
  font-family: var(--font-head);
  font-size: 1.5rem;
  font-weight: 900;
  color: var(--text-dim);
  padding: 12px 20px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  transition: color var(--ease), border-color var(--ease), background var(--ease);
}
.site-nav__link:hover {
  color: var(--gold);
}
.site-nav__link[aria-current="page"] {
  color: var(--gold);
  border-color: var(--line);
  background: rgba(255, 215, 0, 0.06);
}
.site-nav__hint {
  font-family: var(--font-data);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  text-align: center;
  opacity: 0.8;
}

/* ===== 桌面浮标导航 ===== */
.site-rail {
  display: none;
  position: fixed;
  top: 50%;
  right: 14px;
  transform: translateY(-50%);
  z-index: 950;
}
.site-rail__list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 80vh;
  justify-content: center;
}
.site-rail__link {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 44px;
  height: 44px;
  padding: 8px;
  border-radius: 50%;
  border: 1px solid var(--line-violet);
  background: rgba(10, 11, 16, 0.78);
  color: var(--text-dim);
  white-space: nowrap;
  overflow: hidden;
  transition: width var(--ease), border-radius var(--ease), border-color var(--ease), background var(--ease), color var(--ease), box-shadow var(--ease);
}
.site-rail__link:hover,
.site-rail__link:focus-visible {
  width: 112px;
  border-radius: 22px;
  border-color: var(--gold);
  background: var(--bg-elev);
  color: var(--gold);
  box-shadow: var(--glow-gold);
}
.site-rail__index {
  flex: 0 0 auto;
  min-width: 20px;
  font-family: var(--font-data);
  font-size: 0.65rem;
  color: var(--purple);
}
.site-rail__label {
  flex: 0 0 auto;
  font-size: 0.78rem;
  font-weight: 600;
  opacity: 0;
  transition: opacity var(--ease);
}
.site-rail__link:hover .site-rail__label,
.site-rail__link:focus-visible .site-rail__label {
  opacity: 1;
}
.site-rail__link[aria-current="page"] {
  border-color: var(--gold);
  color: var(--gold);
  background: linear-gradient(135deg, rgba(255, 215, 0, 0.14), rgba(138, 43, 226, 0.1));
  box-shadow: var(--glow-gold);
}
.site-rail__link[aria-current="page"] .site-rail__index {
  color: var(--orange);
}
.site-rail__label kbd {
  font-family: var(--font-data);
  font-size: 0.58rem;
  color: var(--purple);
  border: 1px solid var(--line-violet);
  border-radius: 4px;
  padding: 1px 5px;
  margin-left: 4px;
  transition: color var(--ease), border-color var(--ease);
}
.site-rail__link:hover .site-rail__label kbd,
.site-rail__link:focus-visible .site-rail__label kbd {
  color: var(--orange);
  border-color: rgba(255, 107, 53, 0.4);
}

/* ===== 页脚 ===== */
.site-footer {
  position: relative;
  z-index: 1;
  margin-top: 80px;
  padding: 56px 0 0;
  border-top: 1px solid var(--line-violet);
  background:
    radial-gradient(800px 300px at 10% 0%, rgba(138, 43, 226, 0.08), transparent 60%),
    linear-gradient(180deg, rgba(11, 12, 16, 0.6), var(--bg-deep) 40%);
}
.site-footer::before {
  content: '';
  position: absolute;
  top: -1px;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--gold), var(--purple), transparent);
}
.site-footer__inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  padding-bottom: 40px;
}
@media (min-width: 601px) and (max-width: 1023px) {
  .site-footer__inner { grid-template-columns: 1fr 1fr; }
}
@media (min-width: 1024px) {
  .site-footer__inner {
    grid-template-columns: 1.1fr 1.4fr 0.9fr 0.9fr;
  }
}
.site-footer__title {
  display: inline-block;
  font-family: var(--font-head);
  font-size: 0.8rem;
  font-weight: 900;
  letter-spacing: 0.12em;
  color: var(--gold);
  border-bottom: 1px solid var(--line);
  padding-bottom: 6px;
  margin-bottom: 14px;
}
.site-footer__list li {
  margin-bottom: 8px;
  color: var(--text-dim);
  font-size: 0.9rem;
  line-height: 1.7;
}
.site-footer__list a {
  color: var(--text-dim);
}
.site-footer__list a:hover {
  color: var(--gold);
  padding-left: 4px;
}
.site-footer__slogan {
  margin-top: 12px;
  color: var(--text-dim);
  font-size: 0.86rem;
  line-height: 1.8;
  max-width: 34em;
}
.site-footer__meta {
  border-top: 1px solid var(--line);
  background: rgba(6, 7, 11, 0.5);
  padding: 18px 0;
}
.site-footer__meta-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  justify-content: space-between;
  font-family: var(--font-data);
  font-size: 0.76rem;
  color: var(--text-dim);
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 26px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.95rem;
  line-height: 1;
  position: relative;
  transition: transform var(--ease), box-shadow var(--ease), background var(--ease), color var(--ease), border-color var(--ease);
}
.btn:active { transform: scale(0.97); }
.btn--primary {
  background: linear-gradient(135deg, var(--gold), var(--gold-deep));
  color: var(--bg);
  box-shadow: var(--glow-gold);
}
.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(255, 215, 0, 0.32);
}
.btn--ghost {
  border: 1px solid var(--line-violet);
  color: var(--text);
  background: rgba(138, 43, 226, 0.06);
}
.btn--ghost:hover {
  border-color: var(--purple);
  background: rgba(138, 43, 226, 0.16);
  transform: translateY(-2px);
}

/* ===== 面包屑 ===== */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 18px 0 8px;
  font-size: 0.82rem;
  color: var(--text-dim);
}
.breadcrumb a { color: var(--text-dim); }
.breadcrumb a:hover { color: var(--gold); }
.breadcrumb__sep {
  color: var(--purple);
  margin: 0 2px;
}
.breadcrumb [aria-current="page"] { color: var(--gold); }

/* ===== 分区与标题组 ===== */
.section { padding: 56px 0; }
.section__head {
  margin-bottom: 32px;
  max-width: 720px;
}
.section__title { margin-bottom: 10px; }
.section__desc {
  color: var(--text-dim);
  font-size: 1rem;
  max-width: 56em;
}

/* ===== 栅格 ===== */
.grid {
  display: grid;
  gap: 24px;
}
@media (min-width: 601px) and (max-width: 900px) {
  .grid--2,
  .grid--3 { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 901px) {
  .grid--2 { grid-template-columns: repeat(2, 1fr); }
  .grid--3 { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 600px) {
  .grid--2,
  .grid--3 { grid-template-columns: 1fr; }
}

/* ===== 卡片 ===== */
.card {
  position: relative;
  overflow: hidden;
  background: linear-gradient(160deg, var(--bg-elev), var(--bg-elev-2));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  transition: transform var(--ease), border-color var(--ease), box-shadow var(--ease);
}
.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--gold), var(--purple));
  opacity: 0;
  transition: opacity var(--ease);
}
.card:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 215, 0, 0.4);
  box-shadow: var(--shadow-card);
}
.card:hover::before { opacity: 1; }
.card__title { margin-bottom: 10px; }
.card__text {
  color: var(--text-dim);
  font-size: 0.9rem;
  line-height: 1.8;
}
.card__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 16px;
}

/* ===== 标签 ===== */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  border: 1px solid var(--line-violet);
  color: var(--purple);
  background: rgba(138, 43, 226, 0.08);
}
.tag--gold {
  border-color: rgba(255, 215, 0, 0.35);
  color: var(--gold);
  background: rgba(255, 215, 0, 0.06);
}
.tag--orange {
  border-color: rgba(255, 107, 53, 0.4);
  color: var(--orange);
  background: rgba(255, 107, 53, 0.08);
}

/* ===== 数据徽标 ===== */
.data-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border: 1px solid rgba(255, 215, 0, 0.25);
  border-radius: var(--radius-sm);
  background: rgba(255, 215, 0, 0.06);
  font-family: var(--font-data);
  font-size: 0.78rem;
  color: var(--gold-deep);
}

/* ===== 分隔线 ===== */
.divider {
  height: 1px;
  border: 0;
  background: linear-gradient(90deg, transparent, var(--gold-deep), var(--purple), transparent);
  margin: 40px 0;
}

/* ===== 图片容器 ===== */
.media-frame {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, rgba(255, 215, 0, 0.05) 25%, transparent 25%) 0 0 / 24px 24px,
    linear-gradient(315deg, rgba(138, 43, 226, 0.1) 25%, transparent 25%) 0 0 / 24px 24px,
    linear-gradient(160deg, var(--bg-elev), var(--bg-deep));
}
.media-frame::after {
  content: '';
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, rgba(255, 215, 0, 0.04), transparent 40%),
    linear-gradient(315deg, rgba(138, 43, 226, 0.08), transparent 55%);
  pointer-events: none;
}
.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s cubic-bezier(0.2, 0.8, 0.2, 1);
}
.media-frame:hover img { transform: scale(1.04); }

/* ===== 文章正文 ===== */
.content {
  max-width: 46em;
  color: var(--text);
  font-size: 1rem;
  line-height: 2;
}
.content a:not(.btn) {
  color: var(--gold-deep);
  border-bottom: 1px solid rgba(255, 215, 0, 0.3);
}
.content a:not(.btn):hover {
  color: var(--gold);
  border-color: var(--gold);
}
.content p + p { margin-top: 1em; }

/* ===== 返回顶部 ===== */
.to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 940;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  border: 1px solid var(--line-violet);
  background: rgba(15, 16, 22, 0.88);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  color: var(--gold);
  font-family: var(--font-data);
  font-size: 1.1rem;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity var(--ease), transform var(--ease), visibility var(--ease), border-color var(--ease), box-shadow var(--ease);
}
.to-top[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.to-top:hover,
.to-top:focus-visible {
  border-color: var(--gold);
  box-shadow: var(--glow-gold);
}

/* ===== 显现协议 ===== */
[data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
[data-reveal][data-revealed="true"] {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 焦点可见 ===== */
:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ===== 滚动条 ===== */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-track {
  background: var(--bg-deep);
}
::-webkit-scrollbar-thumb {
  background: linear-gradient(var(--purple), var(--purple-deep));
  border-radius: 8px;
  border: 2px solid var(--bg-deep);
}
::-webkit-scrollbar-thumb:hover {
  background: var(--gold-deep);
}
@supports (scrollbar-color: var(--purple) var(--bg-deep)) {
  * {
    scrollbar-color: var(--purple) var(--bg-deep);
    scrollbar-width: thin;
  }
}

/* ===== 响应式 ===== */
@media (min-width: 1024px) {
  body { padding-right: var(--rail-w); }
  .site-nav-toggle { display: none; }
  .site-nav { display: none; }
  .site-rail { display: flex; }
  .site-header__meta { display: flex; }
}
@media (max-width: 1199px) and (min-width: 1024px) {
  .site-header__coords { display: none; }
}
@media (max-width: 480px) {
  .site-brand__tag { display: none; }
}

/* ===== 减少动效 ===== */
@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;
    transition-delay: 0ms !important;
  }
  [data-reveal] {
    opacity: 1;
    transform: none;
  }
}