/* =========================================================
   QY Site Kit — /assets/site.css
   复古出版底色 × 数字操作台结构
   ========================================================= */

/* ---------- 1. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; height: auto; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; padding: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }
::selection { background: var(--path-400); color: var(--ink-900); }

/* ---------- 2. 变量 ---------- */
:root {
  --ink-900: #0A1B2E;
  --ink-700: #12304C;
  --ink-500: #1E4E74;
  --path-400: #35E0D4;
  --path-200: #A8F1EA;
  --action-500: #F0692B;
  --paper-100: #F5EEE2;
  --paper-300: #E2D5BF;
  --rule-900: #2A211A;
  --state-ok: #2F8F6B;
  --state-warn: #D9A21B;

  --font-display: "HarmonyOS Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Noto Sans SC", "HarmonyOS Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --font-serif: "Noto Serif SC", Georgia, "Songti SC", "SimSun", serif;

  --shell: 1240px;
  --gutter: 24px;
  --text-body: 17px;
  --space-section: 96px;

  --shadow-hard: 6px 6px 0 var(--ink-900);
  --shadow-soft: 4px 4px 0 var(--paper-300);
}

@media (max-width: 1024px) {
  :root { --gutter: 20px; --space-section: 72px; }
}
@media (max-width: 640px) {
  :root { --gutter: 16px; --space-section: 56px; --text-body: 16px; }
}

/* ---------- 3. 基础排版 ---------- */
body {
  font-family: var(--font-body);
  font-size: var(--text-body);
  font-weight: 400;
  line-height: 1.85;
  color: var(--ink-900);
  background-color: var(--paper-100);
  background-image:
    repeating-linear-gradient(180deg, rgba(42, 33, 26, .035) 0 1px, rgba(42, 33, 26, 0) 1px 8px),
    radial-gradient(circle at 1px 1px, rgba(10, 27, 46, .07) 1px, rgba(10, 27, 46, 0) 1.7px);
  background-size: 100% 8px, 26px 26px;
  min-height: 100vh;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -.01em;
  color: var(--ink-900);
}
h1 { font-size: clamp(30px, 4.4vw, 40px); }
h2 { font-size: clamp(22px, 2.6vw, 26px); }
h3 { font-size: 19px; }
h4 { font-size: 16px; }

.mono { font-family: var(--font-mono); }
.serif { font-family: var(--font-serif); font-weight: 600; }
.measure { max-width: 36em; }

.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;
}

:focus-visible {
  outline: 2px solid var(--action-500);
  outline-offset: 2px;
  border-radius: 1px;
}

@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

/* ---------- 4. 布局骨架 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.grid-12,
.layout {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}
.layout__rail { grid-column: 1 / 4; }
.layout__main { grid-column: 4 / 13; }

.grid-2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; }

.stack-sm > * + * { margin-top: 12px; }
.stack-md > * + * { margin-top: 24px; }

@media (max-width: 1024px) {
  .layout { display: block; }
  .layout__rail { margin-bottom: 32px; }
  .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
}

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 22px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  line-height: 1.2;
  color: var(--ink-900);
  background: var(--paper-100);
  border: 2px solid var(--rule-900);
  box-shadow: 4px 4px 0 var(--ink-900);
  transition: background-color .16s ease-out, color .16s ease-out,
              box-shadow .16s ease-out, border-color .16s ease-out;
}
.btn:hover { background: var(--ink-900); color: var(--paper-100); box-shadow: 7px 7px 0 rgba(240, 105, 43, .8); }
.btn:active { box-shadow: 2px 2px 0 var(--ink-900); }

.btn--primary {
  background: var(--action-500);
  color: var(--ink-900);
  border-color: var(--rule-900);
  box-shadow: 4px 4px 0 var(--rule-900);
}
.btn--primary:hover { background: #FF7F45; color: var(--ink-900); box-shadow: 7px 7px 0 var(--rule-900); }

.btn--ghost {
  background: transparent;
  color: var(--path-400);
  border-color: var(--path-400);
  box-shadow: none;
}
.btn--ghost:hover { background: var(--path-400); color: var(--ink-900); box-shadow: none; }

.btn--sm { padding: 7px 14px; font-size: 13px; letter-spacing: .06em; }
.btn__arrow { transition: transform .16s ease-out; }
.btn:hover .btn__arrow { transform: translateX(4px); }

.arrow-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  color: var(--ink-900);
  border-bottom: 2px solid var(--path-400);
  padding-bottom: 2px;
  transition: color .16s ease-out, border-color .16s ease-out;
}
.arrow-link:hover { color: var(--action-500); border-bottom-color: var(--action-500); }
.arrow-link__arrow { transition: transform .16s ease-out; }
.arrow-link:hover .arrow-link__arrow { transform: translateX(4px); }

/* ---------- 6. 状态标签与标记 ---------- */
.status-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  line-height: 1.4;
  border: 1px solid currentColor;
  color: var(--path-200);
  background: rgba(168, 241, 234, .10);
}
.status-tag__dot { width: 8px; height: 8px; border-radius: 50%; background: currentColor; flex: none; }
.status-tag--ok { color: #7FD9B4; border-color: rgba(111, 216, 174, .6); background: rgba(47, 143, 107, .16); }
.status-tag--warn { color: #E8C257; border-color: rgba(217, 162, 27, .6); background: rgba(217, 162, 27, .14); }
.status-tag--neutral { color: var(--path-200); border-color: rgba(168, 241, 234, .5); background: rgba(168, 241, 234, .10); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .05em;
  color: var(--ink-700);
  border: 1px solid var(--ink-500);
  background: rgba(168, 241, 234, .30);
}
.tag--ok { color: #1F6B4F; border-color: var(--state-ok); background: rgba(47, 143, 107, .12); }
.tag--warn { color: #8A6410; border-color: var(--state-warn); background: rgba(217, 162, 27, .16); }
.tag--action { color: #B4440F; border-color: var(--action-500); background: rgba(240, 105, 43, .12); }

/* ---------- 7. 页头 ---------- */
.site-header { position: relative; z-index: 60; }

.skip-link {
  position: absolute;
  left: 50%;
  top: -70px;
  transform: translateX(-50%);
  z-index: 300;
  padding: 10px 18px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 14px;
  color: var(--ink-900);
  background: var(--action-500);
  border: 2px solid var(--rule-900);
  transition: top .16s ease-out;
}
.skip-link:focus { top: 10px; }

.scroll-progress {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 3px;
  z-index: 250;
  background: rgba(10, 27, 46, .12);
  pointer-events: none;
}
.scroll-progress__bar {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--path-400), var(--action-500));
}

.masthead {
  background-color: var(--ink-900);
  background-image: radial-gradient(circle at 1px 1px, rgba(53, 224, 212, .14) 1px, rgba(53, 224, 212, 0) 1.7px);
  background-size: 18px 18px;
  color: var(--paper-100);
}
.masthead__grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 16px;
  align-items: center;
  padding-block: 28px 24px;
}
.masthead__utils {
  grid-column: span 3;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
  line-height: 1.6;
  color: rgba(245, 238, 226, .62);
}
.masthead__utils--end { grid-column: 10 / 13; align-items: flex-end; text-align: right; }
.masthead__issue {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .18em;
  color: var(--path-400);
}
.masthead__stamp { letter-spacing: .04em; }

.masthead__brand-block {
  grid-column: 4 / 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  text-align: center;
}
.masthead__brand-block::before { content: ""; width: 56px; height: 3px; background: var(--path-400); }
.masthead__brand {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(30px, 4.6vw, 40px);
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--paper-100);
}
.masthead__brand-mark { color: var(--path-400); margin-left: .16em; letter-spacing: .02em; }
.masthead__tagline { font-size: 13px; letter-spacing: .06em; color: rgba(168, 241, 234, .84); }

.masthead__navrow {
  background: var(--paper-100);
  border-top: 2px solid var(--rule-900);
  border-bottom: 3px solid var(--rule-900);
}
.masthead__navwrap {
  position: relative;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 56px;
}
.main-nav { display: flex; justify-content: center; width: 100%; }
.main-nav__list { display: flex; flex-wrap: wrap; justify-content: center; width: 100%; }
.main-nav__item { display: flex; }
.main-nav__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 15px 20px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: .03em;
  color: var(--ink-900);
  border-bottom: 4px solid transparent;
  transition: background-color .16s ease-out, border-color .16s ease-out, color .16s ease-out;
}
.main-nav__link:hover { background: var(--path-200); border-bottom-color: var(--ink-500); }
.main-nav__link[aria-current="page"] { border-bottom-color: var(--path-400); }
.main-nav__link[aria-current="page"]::after {
  content: "";
  width: 6px; height: 6px;
  background: var(--action-500);
  border-radius: 50%;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: .10em;
  color: var(--ink-900);
}
.nav-toggle__label { line-height: 1; }
.nav-toggle__icon { position: relative; display: block; width: 20px; height: 2px; background: currentColor; }
.nav-toggle__icon::before,
.nav-toggle__icon::after {
  content: "";
  position: absolute;
  left: 0;
  width: 20px; height: 2px;
  background: currentColor;
  transition: transform .16s ease-out;
}
.nav-toggle__icon::before { top: -6px; }
.nav-toggle__icon::after { top: 6px; }
.site-header[data-open] .nav-toggle__icon { background: transparent; }
.site-header[data-open] .nav-toggle__icon::before { transform: translateY(6px) rotate(45deg); }
.site-header[data-open] .nav-toggle__icon::after { transform: translateY(-6px) rotate(-45deg); }

.notice-strip {
  background: var(--path-200);
  color: var(--ink-900);
  border-bottom: 3px solid var(--rule-900);
}
.notice-strip__inner {
  display: flex;
  align-items: center;
  gap: 18px;
  min-height: 44px;
  padding-block: 7px;
}
.notice-strip__label {
  flex: none;
  padding: 3px 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--ink-900);
  background: var(--action-500);
}
.notice-strip__list {
  display: flex;
  align-items: center;
  gap: 28px;
  overflow-x: auto;
  font-size: 13px;
  scrollbar-width: thin;
}
.notice-strip__item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
  padding-bottom: 2px;
  color: var(--ink-900);
  border-bottom: 1px solid transparent;
  transition: border-color .16s ease-out;
}
.notice-strip__item:hover { border-bottom-color: var(--ink-900); }
.notice-strip__num { font-family: var(--font-mono); font-size: 12px; color: var(--ink-700); }

@media (max-width: 1024px) {
  .masthead__grid { grid-template-columns: 1fr; gap: 14px; padding-block: 22px 18px; text-align: center; }
  .masthead__brand-block { grid-column: auto; order: -1; }
  .masthead__utils,
  .masthead__utils--end {
    grid-column: auto;
    flex-direction: row;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    text-align: center;
  }
  .masthead__utils--end { order: 0; }
  .masthead__utils--start { order: 1; }
}

@media (max-width: 860px) {
  .nav-toggle { display: inline-flex; margin-left: auto; }
  .masthead__navwrap { justify-content: flex-start; }
  .main-nav {
    display: none;
    position: absolute;
    left: 0; right: 0; top: 100%;
    background: var(--paper-100);
    border-top: 2px solid var(--rule-900);
    border-bottom: 3px solid var(--rule-900);
  }
  .site-header[data-open] .main-nav { display: block; }
  .main-nav__list { flex-direction: column; align-items: stretch; }
  .main-nav__item { border-bottom: 1px solid var(--paper-300); }
  .main-nav__item:last-child { border-bottom: 0; }
  .main-nav__link {
    width: 100%;
    justify-content: space-between;
    padding: 16px 20px;
    font-size: 16px;
    border-bottom-width: 0;
    border-left: 4px solid transparent;
  }
  .main-nav__link:hover { background: var(--path-200); border-left-color: var(--ink-500); }
  .main-nav__link[aria-current="page"] { border-left-color: var(--path-400); background: rgba(168, 241, 234, .35); }
  .main-nav__link[aria-current="page"]::after { display: none; }
}

@media (max-width: 640px) {
  .masthead__stamp { display: none; }
  .notice-strip__list { gap: 18px; }
  .skip-link { left: var(--gutter); transform: none; }
}

/* ---------- 8. 面包屑与正文容器 ---------- */
.breadcrumbs { padding-block: 22px 0; font-size: 13px; }
.breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  color: var(--ink-500);
}
.breadcrumbs__item { display: flex; align-items: center; gap: 8px; }
.breadcrumbs__item + .breadcrumbs__item::before { content: "/"; color: var(--ink-500); opacity: .5; }
.breadcrumbs__link { color: var(--ink-700); }
.breadcrumbs__link:hover { color: var(--action-500); text-decoration: underline; text-underline-offset: 3px; }

.prose { max-width: 38em; }
.prose > * + * { margin-top: 1.1em; }
.prose h2 { font-size: 24px; margin-top: 2.2em; }
.prose h3 { font-size: 19px; margin-top: 1.8em; }
.prose p { max-width: 36em; }
.prose ul, .prose ol { max-width: 36em; }
.prose li { position: relative; padding-left: 1.4em; margin-top: .5em; }
.prose li::before {
  content: "";
  position: absolute;
  left: 0; top: .78em;
  width: 8px; height: 2px;
  background: var(--action-500);
}
.prose a { color: var(--ink-700); border-bottom: 2px solid var(--path-400); }
.prose a:hover { background: var(--path-200); }
.prose strong { font-weight: 700; }
.prose blockquote {
  padding-left: 20px;
  border-left: 4px solid var(--action-500);
  font-family: var(--font-serif);
  font-size: 19px;
  color: var(--rule-900);
}

/* ---------- 9. 章节与色带 ---------- */
.section { padding-block: var(--space-section); }
.section--tight { padding-block: calc(var(--space-section) / 2); }

.band {
  background-color: var(--ink-900);
  background-image: radial-gradient(circle at 1px 1px, rgba(53, 224, 212, .10) 1px, rgba(53, 224, 212, 0) 1.7px);
  background-size: 18px 18px;
  color: rgba(245, 238, 226, .86);
}
.band--ink { background-color: var(--ink-700); }
.band h1, .band h2, .band h3, .band h4 { color: var(--paper-100); }
.band .card__title, .band .plate__value { color: var(--paper-100); }
.band .section-lede, .band .card__text { color: rgba(245, 238, 226, .78); }
.band .section-kicker { color: var(--path-200); }
.band .section-head { border-bottom-color: var(--path-400); }

.section-head {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
  align-items: end;
  padding-bottom: 24px;
  margin-bottom: 40px;
  border-bottom: 3px solid var(--rule-900);
}
.section-num {
  grid-column: 1 / 4;
  justify-self: start;
  align-self: end;
  display: inline-block;
  padding: 4px 12px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(34px, 5vw, 56px);
  line-height: 1.1;
  letter-spacing: -.04em;
  color: var(--ink-900);
  background: var(--path-400);
  border: 2px solid var(--rule-900);
}
.section-kicker {
  grid-column: 4 / 10;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .2em;
  color: var(--ink-500);
}
.section-title { grid-column: 4 / 10; font-size: clamp(23px, 2.8vw, 26px); }
.section-lede { grid-column: 4 / 10; max-width: 36em; color: var(--ink-700); }
.section-action { grid-column: 10 / 13; justify-self: end; align-self: end; }

@media (max-width: 1024px) {
  .section-num { grid-column: 1 / 3; }
  .section-kicker, .section-title, .section-lede { grid-column: 3 / 13; }
  .section-action { grid-column: 3 / 13; justify-self: start; }
}
@media (max-width: 640px) {
  .section-head { gap: 12px; margin-bottom: 28px; }
  .section-num { grid-column: 1 / 13; }
  .section-kicker, .section-title, .section-lede, .section-action { grid-column: 1 / 13; }
}

.hairline { height: 2px; border: 0; background: var(--rule-900); }
.hairline--cyan {
  height: 2px;
  border: 0;
  background: repeating-linear-gradient(90deg, var(--path-400) 0 24px, transparent 24px 34px);
}

/* ---------- 10. 卡片 / 旁注牌 / 提示 / 参数表 ---------- */
.card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 24px;
  background: var(--paper-100);
  border: 2px solid var(--rule-900);
  box-shadow: var(--shadow-hard);
  transition: box-shadow .16s ease-out, background-color .16s ease-out, border-color .16s ease-out;
}
.card:hover { background: #FBF6EC; box-shadow: 10px 10px 0 var(--ink-900); }
.card--accent { border-left: 4px solid var(--action-500); }
.card--path { border-left: 4px solid var(--path-400); }
.card__label { font-family: var(--font-mono); font-size: 12px; letter-spacing: .16em; color: var(--ink-500); }
.card__title { font-family: var(--font-display); font-weight: 700; font-size: 19px; color: var(--ink-900); }
.card__text { font-size: 15px; line-height: 1.8; color: var(--ink-700); max-width: 34em; }
.card__foot {
  margin-top: auto;
  padding-top: 12px;
  border-top: 1px solid var(--paper-300);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  font-size: 13px;
}
.band .card {
  background: var(--ink-700);
  border-color: var(--path-400);
  box-shadow: 6px 6px 0 rgba(53, 224, 212, .22);
}
.band .card:hover { background: #17405F; box-shadow: 10px 10px 0 rgba(53, 224, 212, .35); }
.band .card__label { color: var(--path-200); }
.band .card__foot { border-top-color: rgba(168, 241, 234, .3); }

.plate {
  padding: 16px 18px;
  background: #FBF6EC;
  border: 2px solid var(--rule-900);
  box-shadow: var(--shadow-soft);
}
.plate__label { font-family: var(--font-mono); font-size: 12px; letter-spacing: .16em; color: var(--action-500); }
.plate__value { font-family: var(--font-display); font-weight: 700; font-size: 22px; margin-top: 6px; color: var(--ink-900); }
.plate__note { font-size: 13px; color: var(--ink-500); margin-top: 6px; }

.callout {
  padding: 20px 24px;
  background: rgba(240, 105, 43, .08);
  border: 2px solid var(--rule-900);
  border-left: 4px solid var(--action-500);
}
.callout--path { background: rgba(53, 224, 212, .12); border-left-color: var(--path-400); }

.spec { border: 2px solid var(--rule-900); background: #FBF6EC; }
.spec__row {
  display: grid;
  grid-template-columns: minmax(120px, 1fr) 2fr;
  gap: 16px;
  align-items: center;
  min-height: 44px;
  padding: 6px 20px;
  border-bottom: 1px solid var(--paper-300);
}
.spec__row:last-child { border-bottom: 0; }
.spec__row:nth-child(even) { background: rgba(226, 213, 191, .38); }
.spec__key { font-size: 14px; color: var(--ink-700); }
.spec__val { font-family: var(--font-mono); font-size: 14px; text-align: right; color: var(--ink-900); }

/* ---------- 11. 章节索引 ---------- */
.index-rail { position: sticky; top: 24px; align-self: start; }
.index-list { display: flex; flex-direction: column; gap: 2px; padding-top: 16px; border-top: 3px solid var(--rule-900); }
.index-list__link {
  display: flex;
  gap: 10px;
  padding: 8px 0 8px 12px;
  font-size: 14px;
  color: var(--ink-500);
  border-left: 3px solid transparent;
  transition: color .16s ease-out, border-color .16s ease-out;
}
.index-list__link:hover { color: var(--ink-900); border-left-color: var(--path-400); }
.index-list__link.is-current { color: var(--ink-900); font-weight: 700; border-left-color: var(--action-500); }
.index-list__num { font-family: var(--font-mono); font-size: 12px; color: var(--ink-500); }
.band .index-list { border-top-color: var(--path-400); }
.band .index-list__link { color: rgba(245, 238, 226, .7); }
.band .index-list__link.is-current { color: var(--paper-100); }

/* ---------- 12. 图文容器 ---------- */
.media {
  position: relative;
  border: 2px solid var(--rule-900);
  box-shadow: var(--shadow-hard);
  background: var(--ink-700);
  overflow: hidden;
}
.media__frame {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  aspect-ratio: 16 / 9;
  background-image: linear-gradient(135deg, var(--ink-900), var(--ink-700) 58%, var(--ink-500));
}
.media__frame::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(90deg, rgba(53, 224, 212, .18) 0 1px, rgba(53, 224, 212, 0) 1px 40px),
    repeating-linear-gradient(0deg, rgba(53, 224, 212, .12) 0 1px, rgba(53, 224, 212, 0) 1px 40px);
}
.media__frame::after {
  content: "";
  position: relative;
  width: 56%;
  height: 2px;
  background: var(--path-400);
  box-shadow: 0 0 12px rgba(53, 224, 212, .8);
}
.media__img { width: 100%; height: 100%; object-fit: cover; }
.media__cap {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--ink-700);
  background: var(--paper-100);
  border-top: 2px solid var(--rule-900);
}
.media--wide .media__frame { aspect-ratio: 21 / 9; }
.media--square .media__frame { aspect-ratio: 1 / 1; }
.media--device .media__frame { aspect-ratio: 4 / 3; }

/* ---------- 13. 分段控件 ---------- */
.segmented {
  display: inline-flex;
  flex-wrap: wrap;
  border: 2px solid var(--rule-900);
  background: var(--paper-100);
}
.segmented__item {
  padding: 10px 18px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--ink-700);
  border-right: 2px solid var(--rule-900);
  transition: background-color .16s ease-out, color .16s ease-out;
}
.segmented__item:last-child { border-right: 0; }
.segmented__item:hover { background: var(--path-200); color: var(--ink-900); }
.segmented__item[aria-selected="true"] { background: var(--ink-900); color: var(--path-400); }

/* ---------- 14. 页脚 ---------- */
.site-footer {
  margin-top: var(--space-section);
  border-top: 4px solid var(--path-400);
  background-color: var(--ink-900);
  background-image: radial-gradient(circle at 1px 1px, rgba(53, 224, 212, .10) 1px, rgba(53, 224, 212, 0) 1.7px);
  background-size: 18px 18px;
  color: rgba(245, 238, 226, .8);
}

.footer__grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 32px;
  padding-block: 64px 40px;
}
.footer__brand { grid-column: 1 / 6; display: flex; flex-direction: column; gap: 14px; }
.footer__logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 24px;
  letter-spacing: -.01em;
  color: var(--paper-100);
}
.footer__logo-mark { color: var(--path-400); margin-left: .16em; }
.footer__note { font-size: 14px; line-height: 1.9; color: rgba(245, 238, 226, .66); max-width: 34em; }
.footer__meta { font-size: 12px; letter-spacing: .12em; color: rgba(168, 241, 234, .75); }

.footer__col { display: flex; flex-direction: column; }
.footer__col--a { grid-column: 6 / 8; }
.footer__col--b { grid-column: 8 / 10; }
.footer__col--c { grid-column: 10 / 13; }
.footer__title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--path-400);
  padding-bottom: 10px;
  margin-bottom: 14px;
  border-bottom: 1px solid rgba(53, 224, 212, .35);
}
.footer__list { display: flex; flex-direction: column; gap: 2px; }
.footer__link {
  display: block;
  padding: 6px 0 6px 10px;
  font-size: 15px;
  color: rgba(245, 238, 226, .8);
  border-left: 2px solid transparent;
  transition: color .16s ease-out, border-color .16s ease-out, padding-left .16s ease-out, background-color .16s ease-out;
}
.footer__link:hover {
  color: var(--path-400);
  border-left-color: var(--path-400);
  padding-left: 14px;
  background: rgba(53, 224, 212, .07);
}

.footer__contact {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 8px 24px;
  align-items: start;
  margin-bottom: 40px;
  padding: 22px 24px;
  border: 2px solid rgba(53, 224, 212, .4);
  background: rgba(53, 224, 212, .06);
}
.footer__contact-title {
  grid-column: 1 / -1;
  font-family: var(--font-display);
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--path-400);
}
.footer__contact-list {
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 8px 24px;
}
.footer__contact-item { display: flex; flex-direction: column; gap: 2px; font-size: 14px; }
.footer__contact-key { font-family: var(--font-mono); font-size: 12px; letter-spacing: .12em; color: rgba(168, 241, 234, .78); }
.footer__contact-val { color: var(--paper-100); word-break: break-word; }
.footer__contact-note {
  grid-column: 1 / -1;
  margin-top: 6px;
  padding-top: 12px;
  font-size: 13px;
  line-height: 1.8;
  color: rgba(245, 238, 226, .62);
  border-top: 1px solid rgba(53, 224, 212, .25);
}

.footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding-block: 20px 44px;
  border-top: 1px solid rgba(53, 224, 212, .25);
  font-size: 13px;
  color: rgba(245, 238, 226, .58);
}
.footer__legal { font-family: var(--font-mono); letter-spacing: .04em; }
.footer__bottom-links { display: flex; flex-wrap: wrap; gap: 18px; }
.footer__bottom-links a { padding-bottom: 2px; border-bottom: 1px solid transparent; transition: color .16s ease-out, border-color .16s ease-out; }
.footer__bottom-links a:hover { color: var(--path-400); border-bottom-color: var(--path-400); }

@media (max-width: 1024px) {
  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px 24px; padding-block: 48px 32px; }
  .footer__brand { grid-column: 1 / -1; }
  .footer__col--a, .footer__col--b, .footer__col--c { grid-column: auto; }
}
@media (max-width: 640px) {
  .footer__grid { grid-template-columns: 1fr; }
  .footer__contact { padding: 18px 16px; }
  .footer__bottom { padding-bottom: 32px; }
}

/* ---------- 15. 显现与动效偏好 ---------- */
html[data-reveal-mode="on"] [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .24s ease-out, transform .24s ease-out;
}
html[data-reveal-mode="on"] [data-reveal].is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  html[data-reveal-mode="on"] [data-reveal] { opacity: 1; transform: none; }
}