/* ==========================================================================
   28杠官网 — 共享样式 /assets/site.css
   深墨蓝基底 · 直角细线 · 精密网格 · 信号橙 / 荧光青功能高亮
   ========================================================================== */

/* ---------- 1. 设计令牌 ---------- */
:root {
  --ink-950: #061525;
  --ink-900: #0a2038;
  --panel-800: #102b47;
  --grid-line: #28425f;
  --signal: #ff6b35;
  --signal-soft: #ff8358;
  --cyan: #4df3d3;
  --mist: #f2f6fa;
  --warm: #b8b2a8;
  --steel: #7f97b2;
  --green: #2ed3a6;
  --amber: #ffb020;
  --coral: #ff5c5c;

  --font-display: 'Barlow Condensed', 'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-body: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', 'Consolas', monospace;

  --wrap: 1320px;
  --pad-x: clamp(18px, 4vw, 56px);
  --gap: clamp(16px, 2.4vw, 32px);
  --line: 1px solid var(--grid-line);
  --dur: 220ms;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 2. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scrollbar-color: var(--grid-line) var(--ink-950);
}

body {
  margin: 0;
  background-color: var(--ink-950);
  color: var(--mist);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image: linear-gradient(90deg, rgba(40, 66, 95, .26) 1px, transparent 1px);
  background-size: calc(100% / 12) 100%;
}

body > * {
  position: relative;
  z-index: 1;
}

h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd, dt { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
table { border-collapse: collapse; width: 100%; }
hr { border: 0; }

/* ---------- 3. 焦点与可访问性 ---------- */
:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

a:focus:not(:focus-visible),
button:focus:not(:focus-visible) { outline: none; }

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 10px 16px;
  background: var(--signal);
  color: var(--ink-950);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  transform: translateY(-180%);
  transition: transform var(--dur) var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible {
  transform: translateY(0);
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.visually-hidden {
  position: absolute !important;
  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;
}

/* ---------- 4. 头部框架 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(6, 21, 37, .96);
  border-top: 2px solid var(--signal);
  border-bottom: var(--line);
  color: var(--mist);
  transition: box-shadow var(--dur) var(--ease);
}

.site-header[data-scrolled] {
  box-shadow: 0 10px 30px rgba(0, 0, 0, .45);
}

.header-frame {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}

.header-mast {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2vw, 32px);
  min-height: 74px;
  padding: 12px 0;
  border-bottom: var(--line);
}

.header-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: none;
}

.header-brand__mark {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  background: var(--signal);
  color: var(--ink-950);
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: .02em;
  flex: none;
}

.header-brand__text {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.header-brand__name {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: .06em;
  color: var(--mist);
}

.header-brand__tag {
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.4;
  letter-spacing: .1em;
  color: var(--steel);
}

.header-note {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  max-width: 340px;
  padding-left: clamp(12px, 2vw, 26px);
  border-left: var(--line);
  font-family: var(--font-mono);
  font-size: 11.5px;
  line-height: 1.5;
  letter-spacing: .04em;
  color: var(--steel);
}

.header-note__dot {
  width: 7px;
  height: 7px;
  flex: none;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(77, 243, 211, .14);
  animation: dot-breathe 2.8s var(--ease) infinite;
}

@keyframes dot-breathe {
  0%, 100% { opacity: 1; }
  50% { opacity: .38; }
}

/* ---------- 5. 移动菜单按钮 ---------- */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border: 1px solid var(--grid-line);
  background: var(--panel-800);
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  line-height: 1;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.nav-toggle:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.nav-toggle[aria-expanded="true"] {
  border-color: var(--signal);
  color: var(--signal);
}

.nav-toggle__bars {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 3px;
  width: 16px;
  flex: none;
}

.nav-toggle__bars span {
  display: block;
  height: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

.nav-toggle__label { white-space: nowrap; }

/* ---------- 6. 主导航 ---------- */
.site-nav { display: block; }

.site-nav__list {
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  gap: 0;
}

.site-nav__item { display: flex; }

.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 15px clamp(10px, 1.5vw, 22px);
  border-bottom: 2px solid transparent;
  color: var(--steel);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: .02em;
  transition: color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              background-color var(--dur) var(--ease);
}

.site-nav__link:hover {
  color: var(--mist);
  border-bottom-color: var(--cyan);
  background: rgba(16, 43, 71, .65);
}

.site-nav__link[aria-current="page"] {
  color: var(--signal);
  border-bottom-color: var(--signal);
  background: rgba(255, 107, 53, .08);
}

.site-nav__index {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .08em;
  color: rgba(127, 151, 178, .75);
}

.site-nav__link[aria-current="page"] .site-nav__index { color: var(--signal); }

.site-nav__text { white-space: nowrap; }

/* ---------- 7. 滚动进度 ---------- */
.scroll-progress {
  position: relative;
  height: 2px;
  background: rgba(40, 66, 95, .55);
}

.scroll-progress__bar {
  display: block;
  height: 100%;
  width: 0;
  background: var(--signal);
}

/* ---------- 8. 页脚 ---------- */
.site-footer {
  position: relative;
  z-index: 2;
  background: var(--ink-900);
  border-top: 1px solid var(--grid-line);
  color: var(--mist);
}

.footer-frame {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: clamp(40px, 6vw, 72px) var(--pad-x) clamp(18px, 3vw, 30px);
}

.footer-top {
  display: grid;
  grid-template-columns: 1.6fr .85fr .85fr 1.35fr;
  gap: var(--gap);
  padding-bottom: clamp(26px, 4vw, 46px);
  border-bottom: var(--line);
}

.footer-brand__mark {
  display: inline-grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--signal);
  color: var(--signal);
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  line-height: 1;
}

.footer-brand__name {
  margin-top: 14px;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: .08em;
  line-height: 1.2;
  color: var(--mist);
}

.footer-desc {
  margin-top: 10px;
  max-width: 34ch;
  font-size: 13px;
  line-height: 1.85;
  color: var(--steel);
}

.footer-group__title {
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--warm);
}

.footer-links {
  display: grid;
  gap: 2px;
}

.footer-link {
  display: inline-block;
  padding: 5px 0;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--steel);
  transition: color 180ms var(--ease);
}

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

.footer-link:focus-visible { color: var(--cyan); }

.footer-link--mono {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .02em;
  word-break: break-all;
}

.footer-contact__list {
  display: grid;
  gap: 10px;
}

.footer-contact__row {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
}

.footer-contact__label {
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.9;
  letter-spacing: .1em;
  color: var(--warm);
}

.footer-contact__value {
  font-size: 13px;
  line-height: 1.75;
  color: var(--steel);
  overflow-wrap: anywhere;
}

.footer-contact__value--mono {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .01em;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  padding-top: clamp(16px, 2.4vw, 24px);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .04em;
  color: var(--steel);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 16px;
}

.footer-mono { color: var(--warm); }

.footer-note { color: var(--steel); }

/* ---------- 9. 布局容器 ---------- */
.container {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--pad-x);
}

.container--narrow { max-width: 880px; }

.section { padding-block: clamp(40px, 6vw, 88px); }

.section--tight { padding-block: clamp(24px, 3vw, 44px); }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 20px;
  padding-bottom: 14px;
  margin-bottom: clamp(20px, 3vw, 36px);
  border-bottom: var(--line);
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.rule {
  display: block;
  width: 100%;
  height: 0;
  border: 0;
  border-top: var(--line);
  margin: 0;
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gap);
}

/* ---------- 10. 面包屑 ---------- */
.breadcrumb {
  padding-block: 13px;
  border-bottom: var(--line);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: var(--steel);
}

.breadcrumb__item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb__link {
  color: var(--steel);
  border-bottom: 1px solid transparent;
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}

.breadcrumb__link:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.breadcrumb__sep { color: var(--grid-line); }

.breadcrumb__item[aria-current="page"],
.breadcrumb__link[aria-current="page"] { color: var(--mist); }

/* ---------- 11. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 22px;
  border: 1px solid var(--grid-line);
  background: transparent;
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.2;
  letter-spacing: .12em;
  text-transform: uppercase;
  transition: background-color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              color var(--dur) var(--ease),
              transform var(--dur) var(--ease);
}

.btn:hover { transform: translateY(-1px); }

.btn--primary {
  background: var(--signal);
  border-color: var(--signal);
  color: var(--ink-950);
  font-weight: 700;
}

.btn--primary:hover {
  background: var(--signal-soft);
  border-color: var(--signal-soft);
}

.btn--ghost {
  border-color: var(--cyan);
  color: var(--cyan);
}

.btn--ghost:hover { background: rgba(77, 243, 211, .1); }

.btn--quiet {
  padding: 9px 15px;
  border-color: var(--grid-line);
  color: var(--steel);
  font-size: 11.5px;
}

.btn--quiet:hover {
  border-color: var(--steel);
  color: var(--mist);
}

/* ---------- 12. 状态与芯片 ---------- */
.status {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 4px 9px;
  border: 1px solid currentColor;
  background: rgba(127, 151, 178, .08);
  color: var(--steel);
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.5;
  letter-spacing: .08em;
  white-space: nowrap;
}

.status__dot {
  width: 6px;
  height: 6px;
  flex: none;
  background: currentColor;
}

.status--live { color: var(--green); background: rgba(46, 211, 166, .1); }
.status--update { color: var(--amber); background: rgba(255, 176, 32, .1); }
.status--down { color: var(--coral); background: rgba(255, 92, 92, .1); }
.status--info { color: var(--cyan); background: rgba(77, 243, 211, .1); }

.chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 12px;
  border: 1px solid var(--grid-line);
  background: var(--panel-800);
  color: var(--steel);
  font-family: var(--font-mono);
  font-size: 11.5px;
  line-height: 1.4;
  letter-spacing: .06em;
  transition: color 180ms var(--ease),
              border-color 180ms var(--ease),
              background-color 180ms var(--ease);
}

.chip:hover {
  border-color: var(--steel);
  color: var(--mist);
}

.chip[aria-pressed="true"],
.chip[data-active] {
  border-color: var(--cyan);
  background: var(--cyan);
  color: var(--ink-950);
}

/* ---------- 13. 图像容器 ---------- */
.media-frame {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  background: var(--ink-900);
  border: 1px solid var(--grid-line);
  overflow: hidden;
}

.media-frame__image,
.media-frame > img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.media-frame__caption {
  position: absolute;
  inset: auto 0 0 0;
  padding: 10px 12px;
  background: linear-gradient(180deg, rgba(6, 21, 37, 0), rgba(6, 21, 37, .94));
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.5;
  letter-spacing: .06em;
  color: var(--warm);
}

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }

/* ---------- 14. 正文排版 ---------- */
.prose {
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

.prose > * + * { margin-top: 1.05em; }

.prose h2 {
  margin-top: 1.7em;
  font-family: var(--font-display);
  font-size: clamp(22px, 2.6vw, 30px);
  font-weight: 700;
  line-height: 1.28;
  letter-spacing: .02em;
}

.prose h3 {
  margin-top: 1.5em;
  font-size: 17px;
  font-weight: 600;
  line-height: 1.5;
  letter-spacing: .01em;
}

.prose p { color: #cfdae6; }
.prose strong { color: var(--mist); font-weight: 600; }

.prose ul { padding-left: 1.1em; }

.prose ul li {
  position: relative;
  padding-left: .85em;
}

.prose ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .82em;
  width: 7px;
  height: 1px;
  background: var(--cyan);
}

.prose ol {
  padding-left: 1.3em;
  list-style: decimal;
}

.prose ol li::marker {
  font-family: var(--font-mono);
  font-size: .85em;
  color: var(--signal);
}

.prose a {
  color: var(--cyan);
  border-bottom: 1px solid rgba(77, 243, 211, .4);
  transition: border-color 180ms var(--ease);
}

.prose a:hover { border-bottom-color: var(--cyan); }

.prose code,
.prose kbd {
  font-family: var(--font-mono);
  font-size: .88em;
  color: var(--cyan);
}

.prose--light {
  padding: clamp(20px, 3vw, 36px);
  background: var(--mist);
  border: 1px solid rgba(40, 66, 95, .18);
  color: var(--ink-900);
}

.prose--light p,
.prose--light li { color: #24384d; }

.prose--light h2,
.prose--light h3,
.prose--light strong { color: var(--ink-950); }

.prose--light a {
  color: #0d6473;
  border-bottom-color: rgba(13, 100, 115, .45);
}

.prose--light ul li::before { background: var(--signal); }

/* ---------- 15. 响应式 ---------- */
@media (max-width: 1180px) {
  .header-note { display: none; }
}

@media (max-width: 1024px) {
  .footer-top { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 900px) {
  .nav-toggle {
    display: inline-flex;
    margin-left: auto;
  }

  .site-nav { display: none; }

  .site-nav[data-open] {
    display: block;
    animation: nav-in 200ms var(--ease) both;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    padding-bottom: 6px;
  }

  .site-nav__item { display: block; }

  .site-nav__link {
    width: 100%;
    padding: 15px 12px;
    border-left: 2px solid transparent;
    border-bottom: 1px solid rgba(40, 66, 95, .6);
    font-size: 15px;
  }

  .site-nav__link:hover {
    background: rgba(16, 43, 71, .6);
    border-bottom-color: rgba(40, 66, 95, .6);
    border-left-color: var(--cyan);
  }

  .site-nav__link[aria-current="page"] {
    border-bottom-color: rgba(40, 66, 95, .6);
    border-left-color: var(--signal);
    background: rgba(255, 107, 53, .1);
  }

  .header-mast { min-height: 66px; }
}

@keyframes nav-in {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 640px) {
  .footer-top {
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
  }

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

  .header-brand__mark {
    width: 38px;
    height: 38px;
    font-size: 20px;
  }

  .header-brand__name { font-size: 19px; }

  .header-brand__tag {
    font-size: 10px;
    letter-spacing: .06em;
  }

  .grid-12 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

/* ---------- 16. 减弱动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }

  .header-note__dot { animation: none; }
  .site-nav[data-open] { animation: none; }
  .btn:hover { transform: none; }
}

/* ---------- 17. 打印 ---------- */
@media print {
  body,
  body::before {
    background: #fff;
    color: #000;
  }

  .site-header,
  .site-footer,
  .skip-link,
  .scroll-progress { display: none !important; }

  .prose p,
  .prose li { color: #000; }
}