/* ==========================================================================
   开元 CN · 共享样式 /assets/site.css
   墨黑 + 宣纸白为底，铜绿为入口色，朱砂红只留给更新与反馈
   ========================================================================== */

*, *::before, *::after { box-sizing: border-box; }

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

body, h1, h2, h3, h4, p, ul, ol, li, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; }
[hidden] { display: none !important; }

:root {
  --ky-ink: #14110F;
  --ky-ink-2: #2B2724;
  --ky-paper: #F6F1E7;
  --ky-paper-2: #EDE3D0;
  --ky-bronze: #1F6A5C;
  --ky-bronze-lt: #2E7D6E;
  --ky-bronze-wash: #D8E6E1;
  --ky-cinnabar: #B4342A;
  --ky-cinnabar-deep: #97281F;
  --ky-cinnabar-wash: #F3DAD6;
  --ky-slate: #5A6469;
  --ky-slate-lt: #98A2A6;

  --ky-font-head: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --ky-font-body: "Source Han Serif SC", "Noto Serif SC", "Songti SC", "STSong", "SimSun", Georgia, serif;
  --ky-font-mono: "JetBrains Mono", "Noto Sans Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Consolas, "Courier New", monospace;

  --ky-r-lg: 28px;
  --ky-r-md: 18px;
  --ky-r-sm: 12px;
  --ky-r-pill: 999px;

  --ky-maxw: 1180px;
  --ky-gutter: clamp(18px, 4vw, 44px);
  --ky-line: 1px solid rgba(152, 162, 166, 0.55);
  --ky-line-soft: 1px solid rgba(20, 17, 15, 0.12);

  --ky-ease: cubic-bezier(0.2, 0.8, 0.2, 1);
  --ky-dur: 200ms;
  --ky-shadow: 0 1px 0 rgba(20, 17, 15, 0.04), 0 14px 26px -20px rgba(20, 17, 15, 0.5);
}

body {
  background: var(--ky-paper);
  color: var(--ky-ink);
  font-family: var(--ky-font-body);
  font-size: 17px;
  line-height: 1.8;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

#main-content { display: block; scroll-margin-top: 92px; }

:focus-visible {
  outline: 2px solid var(--ky-bronze);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------------------------------------------------------------
   通用容器 / 排版
   --------------------------------------------------------------- */

.ky-wrap {
  width: 100%;
  max-width: var(--ky-maxw);
  margin-inline: auto;
  padding-inline: var(--ky-gutter);
}
.ky-wrap--narrow { max-width: 760px; }

.ky-section { padding-block: clamp(38px, 6vw, 76px); }

.ky-h1, .ky-h2, .ky-h3 {
  font-family: var(--ky-font-head);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ky-ink);
  line-height: 1.22;
}
.ky-h1 { font-size: clamp(28px, 4vw, 54px); text-wrap: balance; }
.ky-h2 { font-size: clamp(23px, 2.6vw, 34px); line-height: 1.28; text-wrap: balance; }
.ky-h3 { font-size: clamp(18px, 1.6vw, 21px); line-height: 1.4; font-weight: 700; }

.ky-index {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--ky-font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ky-bronze);
}
.ky-index::before {
  content: "";
  width: 18px;
  height: 1px;
  flex: none;
  background: currentColor;
}

.ky-lede {
  font-family: var(--ky-font-body);
  font-size: clamp(17px, 1.5vw, 19px);
  line-height: 1.8;
  color: var(--ky-ink-2);
  max-width: 62ch;
}

.ky-muted { color: var(--ky-slate); font-size: 15px; line-height: 1.75; }

.ky-mono {
  font-family: var(--ky-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  letter-spacing: 0.02em;
}

.ky-prose {
  font-family: var(--ky-font-body);
  font-size: 17px;
  line-height: 1.8;
  color: var(--ky-ink-2);
  max-width: 68ch;
}
.ky-prose p + p { margin-top: 1.2em; }
.ky-prose h2, .ky-prose h3 {
  font-family: var(--ky-font-head);
  color: var(--ky-ink);
  letter-spacing: -0.01em;
  font-weight: 800;
}
.ky-prose h2 { font-size: 26px; line-height: 1.3; margin-top: 1.9em; margin-bottom: 0.7em; }
.ky-prose h3 { font-size: 20px; line-height: 1.4; margin-top: 1.6em; margin-bottom: 0.6em; }
.ky-prose ul, .ky-prose ol { margin-top: 1em; padding-left: 1.35em; }
.ky-prose ul { list-style: disc; }
.ky-prose ol { list-style: decimal; }
.ky-prose li + li { margin-top: 0.45em; }
.ky-prose strong { color: var(--ky-ink); font-weight: 700; }
.ky-prose a {
  color: var(--ky-bronze);
  border-bottom: 1px solid rgba(31, 106, 92, 0.38);
  transition: border-color var(--ky-dur) var(--ky-ease), color var(--ky-dur) var(--ky-ease);
}
.ky-prose a:hover { color: var(--ky-bronze-lt); border-bottom-color: currentColor; }

/* ---------------------------------------------------------------
   跳过链接
   --------------------------------------------------------------- */

.ky-skip {
  position: fixed;
  left: 16px;
  top: 12px;
  z-index: 300;
  padding: 10px 20px;
  border-radius: var(--ky-r-pill);
  background: var(--ky-ink);
  color: var(--ky-paper);
  font-family: var(--ky-font-head);
  font-size: 14px;
  font-weight: 700;
  transform: translateY(-180%);
  transition: transform 180ms var(--ky-ease);
}
.ky-skip:focus { transform: translateY(0); }

/* ---------------------------------------------------------------
   头部
   --------------------------------------------------------------- */

.ky-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: var(--ky-paper);
  border-bottom: var(--ky-line);
  transition: background var(--ky-dur) var(--ky-ease),
              border-color var(--ky-dur) var(--ky-ease),
              box-shadow var(--ky-dur) var(--ky-ease);
}
.ky-header[data-compact] {
  background: var(--ky-paper-2);
  border-bottom-color: var(--ky-bronze);
  box-shadow: 0 14px 26px -24px rgba(20, 17, 15, 0.7);
}

.ky-ruler {
  height: 7px;
  opacity: 0.62;
  background-image:
    repeating-linear-gradient(90deg, var(--ky-slate-lt) 0 1px, transparent 1px 11px),
    repeating-linear-gradient(90deg, var(--ky-bronze) 0 1px, transparent 1px 55px);
  background-size: 100% 3px, 100% 7px;
  background-position: 0 4px, 0 0;
  background-repeat: repeat-x;
  transition: height var(--ky-dur) var(--ky-ease), opacity var(--ky-dur) var(--ky-ease);
}
.ky-header[data-compact] .ky-ruler { height: 0; opacity: 0; }

.ky-header__bar {
  max-width: var(--ky-maxw);
  margin-inline: auto;
  padding: 14px var(--ky-gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  transition: padding var(--ky-dur) var(--ky-ease);
}
.ky-header[data-compact] .ky-header__bar { padding-block: 9px; }

.ky-brand { display: flex; align-items: center; gap: 12px; min-width: 0; }
.ky-brand__seal {
  position: relative;
  flex: none;
  width: 34px;
  height: 34px;
  border-radius: 9px;
  background: var(--ky-bronze);
  box-shadow: inset 0 0 0 2px rgba(246, 241, 231, 0.5);
  transition: transform var(--ky-dur) var(--ky-ease);
}
.ky-brand__seal::after {
  content: "";
  position: absolute;
  inset: 10px;
  border: 2px solid var(--ky-paper);
  border-radius: 1px;
}
.ky-brand:hover .ky-brand__seal { transform: translateY(-2px); }
.ky-brand__text { display: block; min-width: 0; }
.ky-brand__name {
  display: block;
  font-family: var(--ky-font-head);
  font-weight: 800;
  font-size: 20px;
  line-height: 1.2;
  letter-spacing: 0.01em;
  color: var(--ky-ink);
}
.ky-brand__line {
  display: block;
  margin-top: 2px;
  font-family: var(--ky-font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  line-height: 1.4;
  color: var(--ky-slate);
  white-space: nowrap;
}

.ky-navbtn {
  display: none;
  align-items: center;
  gap: 9px;
  flex: none;
  padding: 9px 15px;
  border-radius: var(--ky-r-pill);
  border: 1px solid rgba(31, 106, 92, 0.4);
  background: var(--ky-paper);
  color: var(--ky-bronze);
  font-family: var(--ky-font-head);
  font-size: 14px;
  font-weight: 700;
  transition: background var(--ky-dur) var(--ky-ease), border-color var(--ky-dur) var(--ky-ease);
}
.ky-navbtn:hover { background: var(--ky-bronze-wash); border-color: var(--ky-bronze); }
.ky-navbtn__bars { display: grid; gap: 4px; width: 17px; flex: none; }
.ky-navbtn__bars i {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform var(--ky-dur) var(--ky-ease), opacity var(--ky-dur) var(--ky-ease);
}
.ky-navbtn[aria-expanded="true"] .ky-navbtn__bars i:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.ky-navbtn[aria-expanded="true"] .ky-navbtn__bars i:nth-child(2) { opacity: 0; }
.ky-navbtn[aria-expanded="true"] .ky-navbtn__bars i:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

.ky-nav {
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.6vw, 24px);
  min-width: 0;
}
.ky-nav__list { display: flex; align-items: center; gap: 2px; }
.ky-nav__list a {
  position: relative;
  display: block;
  padding: 9px 12px;
  border-radius: var(--ky-r-pill);
  font-family: var(--ky-font-head);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--ky-ink-2);
  white-space: nowrap;
  transition: color var(--ky-dur) var(--ky-ease),
              background var(--ky-dur) var(--ky-ease),
              transform var(--ky-dur) var(--ky-ease),
              box-shadow var(--ky-dur) var(--ky-ease);
}
.ky-nav__list a::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 3px;
  width: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--ky-bronze);
  transform: translateX(-50%);
  transition: width var(--ky-dur) var(--ky-ease);
}
.ky-nav__list a:hover {
  color: var(--ky-bronze);
  background: var(--ky-bronze-wash);
  transform: translateY(-2px);
}
.ky-nav__list a:hover::after { width: 16px; }
.ky-nav__list a[aria-current="page"] {
  color: var(--ky-bronze);
  background: var(--ky-bronze-wash);
  box-shadow: inset 0 0 0 1px rgba(31, 106, 92, 0.3);
}
.ky-nav__list a[aria-current="page"]::after { width: 16px; }

.ky-nav__stamp {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-left: clamp(10px, 1.6vw, 20px);
  border-left: var(--ky-line);
  font-family: var(--ky-font-mono);
  font-size: 11.5px;
  letter-spacing: 0.04em;
  color: var(--ky-slate);
  white-space: nowrap;
}
.ky-nav__stamp-v {
  padding: 2px 9px;
  border-radius: var(--ky-r-pill);
  border: 1px solid rgba(31, 106, 92, 0.35);
  background: rgba(216, 230, 225, 0.65);
  color: var(--ky-bronze);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

/* ---------------------------------------------------------------
   页脚
   --------------------------------------------------------------- */

.ky-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 96px);
  background: var(--ky-ink);
  color: var(--ky-paper);
}
.ky-footer::before {
  content: "";
  display: block;
  height: 6px;
  opacity: 0.55;
  background-image:
    repeating-linear-gradient(90deg, var(--ky-bronze-lt) 0 1px, transparent 1px 11px),
    repeating-linear-gradient(90deg, var(--ky-bronze-wash) 0 1px, transparent 1px 55px);
  background-size: 100% 2px, 100% 6px;
  background-position: 0 4px, 0 0;
  background-repeat: repeat-x;
}

.ky-footer__inner {
  max-width: var(--ky-maxw);
  margin-inline: auto;
  padding: clamp(38px, 5.5vw, 64px) var(--ky-gutter) clamp(30px, 4vw, 48px);
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  grid-template-columns: 1.6fr 0.9fr 0.9fr 1.3fr;
}

.ky-footer__seal {
  position: relative;
  display: block;
  width: 32px;
  height: 32px;
  margin-bottom: 14px;
  border-radius: 9px;
  background: var(--ky-bronze);
  box-shadow: inset 0 0 0 2px rgba(246, 241, 231, 0.5);
}
.ky-footer__seal::after {
  content: "";
  position: absolute;
  inset: 9px;
  border: 2px solid var(--ky-paper);
  border-radius: 1px;
}
.ky-footer__name {
  font-family: var(--ky-font-head);
  font-weight: 800;
  font-size: 22px;
  line-height: 1.2;
  letter-spacing: 0.01em;
  color: var(--ky-paper);
}
.ky-footer__slogan {
  margin-top: 9px;
  font-family: var(--ky-font-body);
  font-size: 15px;
  line-height: 1.75;
  color: rgba(246, 241, 231, 0.7);
}
.ky-footer__note {
  margin-top: 16px;
  padding-left: 12px;
  border-left: 2px solid var(--ky-cinnabar);
  font-family: var(--ky-font-body);
  font-size: 14px;
  line-height: 1.75;
  color: rgba(246, 241, 231, 0.74);
  max-width: 34ch;
}

.ky-footer__colTitle {
  padding-bottom: 10px;
  margin-bottom: 14px;
  border-bottom: 1px solid rgba(246, 241, 231, 0.16);
  font-family: var(--ky-font-mono);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ky-bronze-wash);
}
.ky-footer__links li + li { margin-top: 2px; }
.ky-footer__links a {
  display: inline-block;
  padding: 4px 0;
  font-family: var(--ky-font-head);
  font-size: 15px;
  color: rgba(246, 241, 231, 0.84);
  border-bottom: 1px solid transparent;
  transition: color var(--ky-dur) var(--ky-ease),
              border-color var(--ky-dur) var(--ky-ease),
              transform var(--ky-dur) var(--ky-ease);
}
.ky-footer__links a:hover {
  color: var(--ky-bronze-wash);
  border-bottom-color: var(--ky-bronze-wash);
  transform: translateX(3px);
}

.ky-footer__contact { display: grid; gap: 13px; }
.ky-footer__contactItem { display: block; }
.ky-footer__contactKey {
  display: block;
  margin-bottom: 3px;
  font-family: var(--ky-font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--ky-bronze-wash);
  opacity: 0.85;
}
.ky-footer__contactVal {
  display: block;
  font-family: var(--ky-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  line-height: 1.7;
  letter-spacing: 0.01em;
  color: rgba(246, 241, 231, 0.8);
  word-break: break-word;
}

.ky-footer__base {
  max-width: var(--ky-maxw);
  margin-inline: auto;
  padding: 20px var(--ky-gutter) 34px;
  border-top: 1px solid rgba(246, 241, 231, 0.14);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 26px;
  font-family: var(--ky-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: 0.03em;
  color: rgba(246, 241, 231, 0.58);
}
.ky-footer__legal { color: var(--ky-bronze-wash); opacity: 0.85; }
.ky-footer__copy { color: rgba(246, 241, 231, 0.58); }

.ky-footer :focus-visible { outline-color: var(--ky-bronze-wash); }

/* ---------------------------------------------------------------
   按钮 / 标签 / 提示
   --------------------------------------------------------------- */

.ky-btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 12px 24px;
  border-radius: var(--ky-r-pill);
  border: 1px solid var(--ky-bronze);
  background: var(--ky-bronze);
  color: var(--ky-paper);
  font-family: var(--ky-font-head);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.01em;
  transition: background var(--ky-dur) var(--ky-ease),
              border-color var(--ky-dur) var(--ky-ease),
              transform var(--ky-dur) var(--ky-ease),
              box-shadow var(--ky-dur) var(--ky-ease);
}
.ky-btn:hover {
  background: var(--ky-bronze-lt);
  border-color: var(--ky-bronze-lt);
  transform: translateY(-2px);
  box-shadow: var(--ky-shadow);
}
.ky-btn--ghost {
  background: transparent;
  color: var(--ky-bronze);
  border-color: rgba(31, 106, 92, 0.45);
}
.ky-btn--ghost:hover {
  background: var(--ky-bronze-wash);
  color: var(--ky-bronze);
  border-color: var(--ky-bronze);
}
.ky-btn--cinnabar {
  background: var(--ky-cinnabar);
  border-color: var(--ky-cinnabar);
  color: var(--ky-paper);
}
.ky-btn--cinnabar:hover {
  background: var(--ky-cinnabar-deep);
  border-color: var(--ky-cinnabar-deep);
}
.ky-actions { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; }

.ky-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 13px;
  border-radius: var(--ky-r-pill);
  border: 1px solid rgba(31, 106, 92, 0.25);
  background: var(--ky-bronze-wash);
  color: var(--ky-bronze);
  font-family: var(--ky-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: 0.04em;
  line-height: 1.6;
}
.ky-chip--paper {
  background: var(--ky-paper-2);
  border-color: rgba(152, 162, 166, 0.5);
  color: var(--ky-ink-2);
}
.ky-chip--cinnabar {
  background: var(--ky-cinnabar-wash);
  border-color: rgba(180, 52, 42, 0.28);
  color: var(--ky-cinnabar);
}

.ky-note {
  padding: 14px 18px;
  border-left: 3px solid var(--ky-cinnabar);
  border-radius: 0 var(--ky-r-sm) var(--ky-r-sm) 0;
  background: var(--ky-cinnabar-wash);
  color: #6E211A;
  font-family: var(--ky-font-body);
  font-size: 15px;
  line-height: 1.75;
}
.ky-note--bronze {
  border-left-color: var(--ky-bronze);
  background: var(--ky-bronze-wash);
  color: #174F45;
}

/* ---------------------------------------------------------------
   面板 / 网格
   --------------------------------------------------------------- */

.ky-panel {
  display: block;
  padding: clamp(20px, 2.6vw, 30px);
  border: var(--ky-line);
  border-radius: var(--ky-r-lg);
  background: var(--ky-paper);
  transition: transform var(--ky-dur) var(--ky-ease),
              border-color var(--ky-dur) var(--ky-ease),
              box-shadow var(--ky-dur) var(--ky-ease);
}
.ky-panel--tan { background: var(--ky-paper-2); }
.ky-panel--bronze { background: var(--ky-bronze-wash); border-color: rgba(31, 106, 92, 0.28); }
.ky-panel--ink {
  background: var(--ky-ink);
  border-color: var(--ky-ink);
  color: rgba(246, 241, 231, 0.86);
}
.ky-panel--ink .ky-h1,
.ky-panel--ink .ky-h2,
.ky-panel--ink .ky-h3 { color: var(--ky-paper); }
.ky-panel--ink .ky-index { color: var(--ky-bronze-wash); }
.ky-panel--ink .ky-muted { color: rgba(246, 241, 231, 0.66); }
.ky-panel--ink .ky-prose { color: rgba(246, 241, 231, 0.84); }
.ky-panel--ink .ky-btn--ghost {
  color: var(--ky-bronze-wash);
  border-color: rgba(216, 230, 225, 0.42);
}
.ky-panel--ink .ky-btn--ghost:hover {
  background: rgba(216, 230, 225, 0.14);
  color: var(--ky-paper);
  border-color: var(--ky-bronze-wash);
}
a.ky-panel:hover,
a.ky-panel:focus-visible {
  transform: translateY(-2px);
  border-color: var(--ky-bronze);
  box-shadow: var(--ky-shadow);
}

.ky-panel__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px 18px;
  margin-bottom: 14px;
}

.ky-grid {
  display: grid;
  gap: clamp(14px, 1.8vw, 22px);
  grid-template-columns: repeat(12, minmax(0, 1fr));
}
.ky-c3 { grid-column: span 3; }
.ky-c4 { grid-column: span 4; }
.ky-c5 { grid-column: span 5; }
.ky-c6 { grid-column: span 6; }
.ky-c7 { grid-column: span 7; }
.ky-c8 { grid-column: span 8; }
.ky-c9 { grid-column: span 9; }
.ky-c12 { grid-column: span 12; }

/* ---------------------------------------------------------------
   面包屑
   --------------------------------------------------------------- */

.ky-crumb {
  font-family: var(--ky-font-mono);
  font-size: 12px;
  letter-spacing: 0.03em;
  color: var(--ky-slate);
}
.ky-crumb ol { display: flex; flex-wrap: wrap; align-items: center; }
.ky-crumb li { display: inline-flex; align-items: center; }
.ky-crumb li + li::before {
  content: "/";
  margin: 0 9px;
  color: var(--ky-slate-lt);
}
.ky-crumb a {
  color: var(--ky-slate);
  border-bottom: 1px solid transparent;
  transition: color var(--ky-dur) var(--ky-ease), border-color var(--ky-dur) var(--ky-ease);
}
.ky-crumb a:hover { color: var(--ky-bronze); border-bottom-color: rgba(31, 106, 92, 0.4); }
.ky-crumb [aria-current="page"] { color: var(--ky-ink); }

/* ---------------------------------------------------------------
   图片容器（页面阶段把 img 放进 frame）
   --------------------------------------------------------------- */

.ky-figure { display: block; margin: 0; }
.ky-figure__frame {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: var(--ky-line);
  border-radius: var(--ky-r-lg);
  background: var(--ky-paper-2);
}
.ky-figure__frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 320ms var(--ky-ease);
}
.ky-figure:hover .ky-figure__frame img { transform: scale(1.02); }
.ky-figure__frame--empty::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(90deg, rgba(152, 162, 166, 0.28) 0 1px, transparent 1px 14px),
    repeating-linear-gradient(0deg, rgba(152, 162, 166, 0.16) 0 1px, transparent 1px 14px);
}
.ky-figure--wide .ky-figure__frame { aspect-ratio: 21 / 9; }
.ky-figure--screen .ky-figure__frame { aspect-ratio: 16 / 9; }
.ky-figure--square .ky-figure__frame { aspect-ratio: 1 / 1; }
.ky-figure--tall .ky-figure__frame { aspect-ratio: 4 / 5; }
.ky-figure__cap {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-top: 10px;
  font-family: var(--ky-font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--ky-slate);
}
.ky-figure__cap::before {
  content: "";
  flex: none;
  width: 14px;
  height: 1px;
  background: var(--ky-slate-lt);
}

/* ---------------------------------------------------------------
   刻度轴 / 目录 / 标签带 / 折叠 / 表格
   --------------------------------------------------------------- */

.ky-axis { position: relative; padding-left: 34px; }
.ky-axis::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: repeating-linear-gradient(180deg, rgba(152, 162, 166, 0.7) 0 6px, transparent 6px 12px);
}
.ky-axis__item { position: relative; padding-bottom: clamp(22px, 3vw, 34px); }
.ky-axis__item::before {
  content: "";
  position: absolute;
  left: -34px;
  top: 7px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  border: 2px solid var(--ky-bronze);
  background: var(--ky-paper);
}
.ky-axis__meta {
  display: block;
  margin-bottom: 6px;
  font-family: var(--ky-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ky-bronze);
}

.ky-toc { font-family: var(--ky-font-head); font-size: 14.5px; }
.ky-toc__link {
  display: block;
  padding: 8px 12px;
  border-left: 2px solid transparent;
  border-radius: 0 var(--ky-r-sm) var(--ky-r-sm) 0;
  color: var(--ky-slate);
  transition: color var(--ky-dur) var(--ky-ease),
              background var(--ky-dur) var(--ky-ease),
              border-color var(--ky-dur) var(--ky-ease);
}
.ky-toc__link:hover { color: var(--ky-bronze); background: rgba(216, 230, 225, 0.5); }
.ky-toc__link[aria-current="location"] {
  color: var(--ky-bronze);
  background: var(--ky-bronze-wash);
  border-left-color: var(--ky-bronze);
}

.ky-tabs {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 8px;
  border-bottom: var(--ky-line);
  scrollbar-width: thin;
}
.ky-tabs__btn {
  flex: none;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 9px 16px;
  border-radius: var(--ky-r-pill);
  border: 1px solid transparent;
  background: transparent;
  color: var(--ky-slate);
  font-family: var(--ky-font-head);
  font-size: 14px;
  font-weight: 600;
  white-space: nowrap;
  transition: color var(--ky-dur) var(--ky-ease),
              background var(--ky-dur) var(--ky-ease),
              border-color var(--ky-dur) var(--ky-ease),
              transform var(--ky-dur) var(--ky-ease);
}
.ky-tabs__btn:hover {
  color: var(--ky-bronze);
  background: var(--ky-bronze-wash);
  transform: translateY(-2px);
}
.ky-tabs__btn[aria-selected="true"] {
  color: var(--ky-paper);
  background: var(--ky-bronze);
  border-color: var(--ky-bronze);
}
.ky-tabs__count {
  font-family: var(--ky-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 11.5px;
  opacity: 0.75;
}
.ky-tabpanel { padding-top: clamp(18px, 2.6vw, 28px); }

.ky-fold {
  border: var(--ky-line);
  border-radius: var(--ky-r-md);
  background: var(--ky-paper);
  overflow: hidden;
}
.ky-fold + .ky-fold { margin-top: 12px; }
.ky-fold__btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 15px 20px;
  text-align: left;
  font-family: var(--ky-font-head);
  font-size: 16px;
  font-weight: 700;
  color: var(--ky-ink);
  transition: background var(--ky-dur) var(--ky-ease), color var(--ky-dur) var(--ky-ease);
}
.ky-fold__btn:hover { background: var(--ky-bronze-wash); color: var(--ky-bronze); }
.ky-fold__btn[aria-expanded="true"] { background: var(--ky-bronze-wash); color: var(--ky-bronze); }
.ky-fold__sign {
  position: relative;
  flex: none;
  width: 22px;
  height: 22px;
  border: 1px solid var(--ky-slate-lt);
  border-radius: 50%;
  transition: border-color var(--ky-dur) var(--ky-ease);
}
.ky-fold__btn[aria-expanded="true"] .ky-fold__sign { border-color: var(--ky-bronze); }
.ky-fold__sign::before,
.ky-fold__sign::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  background: var(--ky-bronze);
  transform: translate(-50%, -50%);
  transition: opacity var(--ky-dur) var(--ky-ease);
}
.ky-fold__sign::before { width: 10px; height: 2px; border-radius: 2px; }
.ky-fold__sign::after { width: 2px; height: 10px; border-radius: 2px; }
.ky-fold__btn[aria-expanded="true"] .ky-fold__sign::after { opacity: 0; }
.ky-fold__panel {
  padding: 0 20px 18px;
  font-family: var(--ky-font-body);
  font-size: 16px;
  line-height: 1.8;
  color: var(--ky-ink-2);
}
.ky-fold__panel:not([hidden]) { animation: ky-reveal 220ms var(--ky-ease) both; }
@keyframes ky-reveal {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: none; }
}

.ky-table { width: 100%; font-family: var(--ky-font-body); font-size: 15px; }
.ky-table caption {
  padding-bottom: 10px;
  text-align: left;
  font-family: var(--ky-font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--ky-slate);
}
.ky-table th {
  padding: 11px 14px;
  text-align: left;
  background: var(--ky-paper-2);
  border-bottom: 1px solid rgba(31, 106, 92, 0.35);
  font-family: var(--ky-font-head);
  font-size: 13px;
  font-weight: 700;
  color: var(--ky-ink);
}
.ky-table td {
  padding: 11px 14px;
  border-bottom: var(--ky-line);
  color: var(--ky-ink-2);
}
.ky-table tbody tr:nth-child(even) { background: rgba(237, 227, 208, 0.5); }
.ky-table__num {
  font-family: var(--ky-font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
}

/* ---------------------------------------------------------------
   滚动进度
   --------------------------------------------------------------- */

.ky-progress {
  position: fixed;
  left: 0;
  top: 0;
  width: 100%;
  height: 2px;
  z-index: 200;
  pointer-events: none;
  background: var(--ky-bronze);
  transform: scaleX(0);
  transform-origin: 0 50%;
}

/* ---------------------------------------------------------------
   响应式
   --------------------------------------------------------------- */

@media (max-width: 1024px) {
  .ky-c3, .ky-c4 { grid-column: span 6; }
  .ky-c5, .ky-c7, .ky-c8, .ky-c9 { grid-column: span 12; }
  .ky-footer__inner { grid-template-columns: 1fr 1fr; }
  .ky-footer__brand { grid-column: 1 / -1; }
}

@media (max-width: 900px) {
  .ky-navbtn { display: inline-flex; }
  .ky-header__bar { flex-wrap: wrap; }
  .ky-brand__line { display: none; }
  .ky-nav {
    display: none;
    flex-basis: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    margin-top: 12px;
    padding-top: 12px;
    border-top: var(--ky-line);
  }
  .ky-nav[data-open] { display: flex; }
  .ky-nav__list {
    flex-direction: row;
    flex-wrap: nowrap;
    gap: 6px;
    overflow-x: auto;
    padding-bottom: 6px;
    scrollbar-width: thin;
    -webkit-overflow-scrolling: touch;
  }
  .ky-nav__list li { flex: none; }
  .ky-nav__list a {
    padding: 8px 14px;
    border: 1px solid rgba(152, 162, 166, 0.5);
  }
  .ky-nav__list a:hover { transform: none; }
  .ky-nav__list a[aria-current="page"] { border-color: var(--ky-bronze); }
  .ky-nav__stamp {
    padding-top: 10px;
    padding-left: 0;
    border-left: 0;
    border-top: var(--ky-line);
  }
  #main-content { scroll-margin-top: 76px; }
}

@media (max-width: 720px) {
  body { font-size: 16.5px; }
  .ky-c3, .ky-c4, .ky-c6 { grid-column: span 12; }
  .ky-grid { gap: 14px; }
  .ky-footer__inner { grid-template-columns: 1fr; }
  .ky-footer__base { flex-direction: column; align-items: flex-start; }
  .ky-actions .ky-btn { width: 100%; justify-content: center; }
}

@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;
  }
  .ky-figure:hover .ky-figure__frame img { transform: none; }
  .ky-btn:hover,
  a.ky-panel:hover,
  a.ky-panel:focus-visible,
  .ky-nav__list a:hover,
  .ky-tabs__btn:hover,
  .ky-brand:hover .ky-brand__seal { transform: none; }
}