:root {
  --bg: #0a0d1f;
  --bg-purple: #100b27;
  --surface: rgba(20, 24, 48, 0.74);
  --surface-solid: #141830;
  --border: rgba(255, 255, 255, 0.09);
  --border-strong: rgba(255, 255, 255, 0.17);
  --text: #fff;
  --text-secondary: rgba(255, 255, 255, 0.7);
  --text-tertiary: rgba(255, 255, 255, 0.46);
  --accent: #ff5722;
  --accent-hover: #ff7043;
  /* 中文走系统字体：苹方(macOS/iOS) / HarmonyOS Sans(华为) / 微软雅黑(Windows) / 思源(Android)
     Inter 只覆盖拉丁与数字，中文会自动落到后面的系统字体，不额外下载中文字体分片 */
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'HarmonyOS Sans SC',
    'Microsoft YaHei', 'Hiragino Sans GB', 'Segoe UI', Roboto, 'Noto Sans SC', sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  color: var(--text);
  background:
    radial-gradient(ellipse 80% 45% at 10% 0%, rgba(30, 64, 175, 0.24), transparent 62%),
    radial-gradient(ellipse 60% 38% at 90% 8%, rgba(109, 40, 217, 0.19), transparent 62%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-purple) 58%, #0b0920 100%);
  font-family: var(--font);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.62;
  background-image:
    radial-gradient(1px 1px at 20px 30px, rgba(255,255,255,.6), transparent),
    radial-gradient(1px 1px at 120px 80px, rgba(255,255,255,.4), transparent),
    radial-gradient(1px 1px at 240px 20px, rgba(255,255,255,.52), transparent),
    radial-gradient(2px 2px at 330px 140px, rgba(180,205,255,.55), transparent),
    radial-gradient(1px 1px at 470px 70px, rgba(255,255,255,.38), transparent);
  background-size: 560px 240px;
}

a { color: inherit; }
button, input, textarea, select { font: inherit; }
[hidden] { display: none !important; }
::selection { color: #fff; background: var(--accent); }

.article-shell {
  width: min(1180px, calc(100% - 96px));
  margin: 0 auto;
}

.article-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(8, 11, 29, 0.94);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(16px);
}
.article-nav-inner {
  width: min(1775px, calc(100% - 128px));
  height: 88px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 220px 1fr 130px;
  align-items: center;
  gap: 24px;
}
.article-logo { display: inline-flex; width: fit-content; }
.article-logo img {
  display: block;
  width: 52px;
  height: 52px;
  object-fit: cover;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 8px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}
.article-nav-links { display: flex; justify-content: center; gap: 42px; }
.article-nav-links a {
  color: var(--text-secondary);
  font-size: 15px;
  text-decoration: none;
  white-space: nowrap;
  transition: color .2s ease;
}
.article-nav-links a:hover, .article-nav-links .is-active { color: #fff; }
.article-nav-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  color: #fff;
  background: var(--accent);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
}
.article-nav-cta:hover { background: var(--accent-hover); }

.article-state {
  width: min(760px, calc(100% - 48px));
  min-height: calc(100vh - 88px);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}
.article-state-index { color: var(--accent); font-weight: 700; letter-spacing: 5px; }
.article-state h1 { margin: 18px 0 12px; font-size: clamp(30px, 5vw, 54px); line-height: 1.2; }
.article-state p { max-width: 540px; margin: 0; color: var(--text-secondary); }
.article-loading-line {
  width: 180px;
  height: 2px;
  margin-top: 32px;
  overflow: hidden;
  background: var(--border);
}
.article-loading-line::after {
  content: '';
  display: block;
  width: 45%;
  height: 100%;
  background: var(--accent);
  animation: loading 1.1s ease-in-out infinite alternate;
}
@keyframes loading { from { transform: translateX(-100%); } to { transform: translateX(220%); } }
.article-state-actions { display: flex; gap: 12px; margin-top: 28px; }
.article-state-actions button, .article-state-actions a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 22px;
  border: 1px solid var(--border-strong);
  color: #fff;
  background: transparent;
  text-decoration: none;
  cursor: pointer;
}
.article-state-actions button { border-color: var(--accent); background: var(--accent); }

.article-breadcrumb { margin: 0 0 56px; font-size: 13px; }
.article-breadcrumb ol {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  margin: 0;
  padding: 0;
  list-style: none;
}
.article-breadcrumb li { display: flex; align-items: center; min-width: 0; color: rgba(255, 255, 255, 0.58); }
.article-breadcrumb li + li::before {
  content: '/';
  margin: 0 10px;
  color: rgba(255, 255, 255, 0.22);
}
.article-breadcrumb a {
  color: rgba(255, 255, 255, 0.58);
  text-decoration: none;
  white-space: nowrap;
  transition: color .2s ease;
}
.article-breadcrumb a:hover, .article-breadcrumb a:focus-visible { color: var(--accent); }
.article-breadcrumb [aria-current] {
  display: block;
  max-width: 44vw;
  overflow: hidden;
  color: rgba(255, 255, 255, 0.86);
  text-overflow: ellipsis;
  white-space: nowrap;
}

.article-hero {
  padding: 78px 0 64px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(135deg, rgba(28, 35, 76, 0.56), rgba(18, 10, 45, 0.35));
}
.article-back {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 62px;
  color: var(--text-tertiary);
  font-size: 13px;
  text-decoration: none;
}
.article-back:hover { color: var(--accent); }
.article-eyebrow {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-bottom: 20px;
  font-size: 12px;
  letter-spacing: 1px;
  text-transform: uppercase;
}
.article-eyebrow span { color: var(--accent); font-weight: 700; }
.article-eyebrow time { color: var(--text-tertiary); }
.article-hero h1 {
  max-width: 960px;
  margin: 0;
  font-size: clamp(36px, 5.3vw, 68px);
  line-height: 1.2;
  letter-spacing: 0;
}
.article-excerpt {
  max-width: 820px;
  margin: 28px 0 0;
  color: var(--text-secondary);
  font-size: 18px;
  line-height: 1.9;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 790px) 270px;
  justify-content: space-between;
  gap: 72px;
  padding-top: 72px;
  padding-bottom: 104px;
}
.article-main { min-width: 0; }
.article-cover-wrap { margin: 0 0 48px; }
.article-cover { display: block; width: 100%; max-height: 560px; object-fit: cover; border: 1px solid var(--border); }
.article-body { color: rgba(255, 255, 255, 0.82); font-size: 17px; line-height: 2; }
.article-body > :first-child { margin-top: 0; }
.article-body p { margin: 0 0 24px; }
.article-body h2 {
  margin: 58px 0 22px;
  padding-left: 20px;
  border-left: 3px solid var(--accent);
  color: #fff;
  font-size: 29px;
  line-height: 1.45;
}
.article-body h3 { margin: 40px 0 16px; color: #fff; font-size: 22px; }
.article-body strong { color: #fff; font-weight: 700; }
.article-body a { color: var(--accent); text-underline-offset: 4px; }
.article-body img {
  display: block;
  width: auto;
  max-width: 100%;
  height: auto;
  max-height: 720px;
  margin: 34px auto;
  object-fit: contain;
  border: 1px solid var(--border);
}
.article-body ul, .article-body ol { margin: 20px 0 28px; padding-left: 28px; }
.article-body li { margin: 10px 0; padding-left: 5px; }
.article-body blockquote {
  margin: 32px 0;
  padding: 22px 26px;
  border-left: 3px solid var(--accent);
  color: var(--text-secondary);
  background: var(--surface);
}
.article-body code { padding: 2px 7px; color: #fff; background: var(--surface-solid); }
.article-body table { width: 100%; margin: 28px 0; border-collapse: collapse; font-size: 14px; }
.article-body th, .article-body td { padding: 12px; border: 1px solid var(--border-strong); text-align: left; }
.article-body th { color: #fff; background: var(--surface); }
.article-end { display: flex; align-items: center; gap: 20px; margin-top: 64px; color: var(--text-tertiary); letter-spacing: 5px; }
.article-end::before, .article-end::after { content: ''; height: 1px; flex: 1; background: var(--border); }

.article-aside { position: relative; }
.article-aside-block {
  position: sticky;
  top: 120px;
  padding: 30px;
  border: 1px solid var(--border);
  background: var(--surface);
}
.article-aside-label { color: var(--accent); font-size: 11px; font-weight: 700; letter-spacing: 2px; }
.article-aside h2 { margin: 18px 0; font-size: 21px; line-height: 1.6; }
.article-aside p { margin: 0 0 22px; color: var(--text-secondary); font-size: 13px; }
.article-aside a, .article-aside button {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 0;
  border: 0;
  color: var(--accent);
  background: transparent;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
}
.article-share { position: static; margin-top: 20px; }
.article-share p { min-height: 20px; margin: 8px 0 0; color: #66d9a0; }

.related-section { padding: 88px 0 110px; border-top: 1px solid var(--border); background: rgba(6, 8, 25, 0.34); }
.related-head { display: flex; align-items: flex-end; justify-content: space-between; margin-bottom: 38px; }
.related-head span { color: var(--accent); font-size: 11px; font-weight: 700; letter-spacing: 2px; }
.related-head h2 { margin: 10px 0 0; font-size: 34px; }
.related-head > a { color: var(--text-secondary); font-size: 13px; text-decoration: none; }
.related-list { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1px; background: var(--border); border: 1px solid var(--border); }
.related-card,
.related-card:link,
.related-card:visited,
.related-card:hover,
.related-card:active {
  display: flex;
  flex-direction: column;
  min-height: 270px;
  padding: 30px;
  color: inherit;
  background: var(--surface-solid);
  text-decoration: none !important;
  text-decoration-line: none !important;
  transition: background .2s ease;
}
.related-card:hover { background: #1b203f; }
.related-card:focus-visible { outline: 2px solid var(--accent); outline-offset: -2px; }
.related-card > * { text-decoration: none !important; text-decoration-line: none !important; }
.related-card-meta { display: flex; justify-content: space-between; gap: 16px; color: var(--text-tertiary); font-size: 11px; }
.related-card-meta span:first-child { color: var(--accent); }
.related-card h3 { margin: 32px 0 18px; font-size: 19px; line-height: 1.55; }
.related-card p { margin: 0; color: var(--text-secondary); font-size: 13px; display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.related-card-more { margin-top: auto; padding-top: 24px; color: var(--accent); font-size: 13px; }

.article-footer { border-top: 1px solid var(--border); background: rgba(5, 7, 20, 0.74); }
.article-footer-inner { min-height: 190px; display: flex; align-items: center; justify-content: space-between; gap: 40px; }
.article-footer img { display: block; width: 126px; height: 52px; object-fit: contain; }
.article-footer p { margin: 12px 0 0; color: var(--text-tertiary); font-size: 12px; }
.article-footer-meta { text-align: right; }
.article-footer-meta p { margin: 4px 0; }

@media (max-width: 1080px) {
  .article-nav-inner { width: min(100% - 48px, 1180px); grid-template-columns: 160px 1fr 120px; }
  .article-nav-links { gap: 24px; }
  .article-layout { grid-template-columns: minmax(0, 1fr) 240px; gap: 44px; }
}

@media (max-width: 820px) {
  .article-shell { width: min(100% - 40px, 720px); }
  .article-nav-inner { width: calc(100% - 40px); height: 72px; grid-template-columns: 1fr auto; }
  .article-logo img { width: 44px; height: 44px; border-radius: 7px; }
  .article-nav-links { display: none; }
  .article-nav-cta { min-height: 40px; padding: 0 18px; }
  .article-hero { padding: 50px 0 44px; }
  .article-back { margin-bottom: 40px; }
  .article-breadcrumb { margin-bottom: 32px; }
  .article-breadcrumb [aria-current] { max-width: 62vw; }
  .article-hero h1 { font-size: clamp(32px, 9vw, 48px); }
  .article-excerpt { font-size: 16px; }
  .article-layout { display: block; padding-top: 42px; padding-bottom: 72px; }
  .article-aside { margin-top: 52px; }
  .article-aside-block { position: static; }
  .related-list { grid-template-columns: 1fr; }
  .related-card { min-height: 230px; }
  .article-footer-inner { padding: 38px 0; align-items: flex-start; flex-direction: column; }
  .article-footer-meta { text-align: left; }
}

@media (max-width: 520px) {
  .article-shell { width: calc(100% - 32px); }
  .article-nav-inner { width: calc(100% - 32px); }
  .article-nav-cta { font-size: 13px; }
  .article-hero { padding-top: 36px; }
  .article-breadcrumb { margin-bottom: 26px; font-size: 12px; }
  .article-breadcrumb a, .article-breadcrumb li { min-height: 22px; }
  .article-breadcrumb [aria-current] { max-width: 100%; }
  .article-eyebrow { align-items: flex-start; flex-direction: column; gap: 6px; }
  .article-hero h1 { font-size: 32px; }
  .article-body { font-size: 16px; line-height: 1.9; }
  .article-body h2 { margin-top: 46px; font-size: 23px; }
  .article-body h3 { font-size: 20px; }
  .article-body img { margin: 26px auto; }
  .related-section { padding: 62px 0 76px; }
  .related-head { align-items: flex-start; flex-direction: column; gap: 16px; }
  .article-state-actions { width: 100%; flex-direction: column; }
}

/* 屏幕阅读器/爬虫可见、视觉隐藏（用于补齐标题层级，不影响设计） */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}