/* ===========================================================================
   九五至尊3 CN 官网 · 坐标站
   /assets/site.css —— 全站共享外壳样式
   框架式导航 / 玄青底 / 帝王紫与鎏金 / 切角面板
   =========================================================================== */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, h5, h6,
p, ul, ol, li, figure, figcaption, blockquote, dl, dd { margin: 0; }

ul, ol { padding: 0; list-style: none; }

img, svg, video { 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; width: 100%; }

/* ---------- 2. 设计令牌 ---------- */
:root {
  --ink: #0B0E1A;
  --ink-2: #141A2E;
  --purple-deep: #2A1B4D;
  --purple: #5B3AA6;
  --purple-light: #8B6BE0;
  --gold: #C9A227;
  --gold-light: #EAD48A;
  --cinnabar: #C0392B;
  --porcelain: #F7F4EC;
  --edge: #38405C;

  --rail: 88px;
  --topbar: 56px;
  --cut: 24px;

  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", serif;
  --font-brush: "ZCOOL XiaoWei", "Noto Serif SC", "Songti SC", serif;
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "DIN Alternate", "Roboto Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;

  --gutter: clamp(20px, 4vw, 64px);
  --measure: 64ch;

  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  padding-left: var(--rail);
  padding-top: var(--topbar);
  background-color: var(--ink);
  background-image:
    radial-gradient(1100px 560px at 88% -12%, rgba(91, 58, 166, .30), transparent 62%),
    radial-gradient(900px 520px at -12% 108%, rgba(42, 27, 77, .55), transparent 68%);
  background-repeat: no-repeat;
  color: var(--porcelain);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.85;
  letter-spacing: .01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, .h1 {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(38px, 7vw, 92px);
  line-height: 1.05;
  letter-spacing: -.02em;
}

h2, .h2 {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(28px, 4vw, 52px);
  line-height: 1.15;
  letter-spacing: -.015em;
}

h3, .h3 {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(20px, 2vw, 28px);
  line-height: 1.35;
  letter-spacing: -.005em;
}

h4, .h4 {
  font-size: 18px;
  font-weight: 700;
  line-height: 1.5;
}

p { max-width: 78ch; }

::selection { background: var(--gold); color: var(--ink); }

:where(a, button, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--gold-light);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- 4. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: -120px;
  left: 16px;
  z-index: 200;
  padding: 10px 20px;
  background: var(--gold);
  color: #17110A;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .08em;
  border-radius: 0 0 4px 4px;
  transition: top .22s var(--ease);
}

.skip-link:focus-visible { top: 0; }

/* ---------- 5. 滚动进度条 ---------- */
.scroll-progress {
  position: fixed;
  inset: 0 0 auto 0;
  height: 2px;
  z-index: 120;
  pointer-events: none;
}

.scroll-progress__bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--purple-light), var(--gold) 55%, var(--gold-light));
}

/* ---------- 6. 框架式页头 ---------- */
.site-header { position: relative; z-index: 90; }

.frame-top {
  position: fixed;
  top: 0;
  left: var(--rail);
  right: 0;
  height: var(--topbar);
  z-index: 80;
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
  padding: 0 clamp(16px, 2.4vw, 34px);
  background: rgba(11, 14, 26, .84);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--edge);
  transition: background-color .3s var(--ease), border-color .3s var(--ease);
}

.site-header[data-scrolled] .frame-top {
  background: rgba(11, 14, 26, .97);
  border-bottom-color: var(--gold);
}

/* 品牌 */
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
  margin-right: auto;
}

.brand__seal {
  flex: 0 0 auto;
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  font-family: var(--font-brush);
  font-size: 13px;
  line-height: 1;
  letter-spacing: .04em;
  color: var(--gold-light);
  background: linear-gradient(150deg, var(--purple-deep), var(--ink));
  border: 1px solid var(--gold);
  border-radius: 3px;
  box-shadow: 0 0 0 1px rgba(201, 162, 39, .16), inset 0 0 12px rgba(201, 162, 39, .24);
  transition: box-shadow .25s var(--ease), color .25s var(--ease);
}

.brand:hover .brand__seal { box-shadow: 0 0 0 1px rgba(201, 162, 39, .5), inset 0 0 16px rgba(201, 162, 39, .4); }

.brand__seal--lg { width: 48px; height: 48px; font-size: 17px; }

.brand__name {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: .04em;
  color: var(--porcelain);
  white-space: nowrap;
}

.brand__sub {
  padding-left: 12px;
  border-left: 1px solid var(--edge);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--gold);
  white-space: nowrap;
}

/* 移动端目录按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 8px 13px;
  color: var(--porcelain);
  font-size: 13px;
  letter-spacing: .14em;
  border: 1px solid var(--edge);
  border-radius: 2px;
  transition: color .22s var(--ease), border-color .22s var(--ease), background-color .22s var(--ease);
}

.nav-toggle__bars { display: grid; gap: 4px; width: 16px; }

.nav-toggle__bars i {
  display: block;
  height: 1.5px;
  background: currentColor;
  transition: transform .25s var(--ease), opacity .2s var(--ease);
}

.nav-toggle__label { font-size: 12px; letter-spacing: .14em; }

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

.nav-toggle[aria-expanded="true"] {
  color: var(--gold-light);
  border-color: var(--gold);
  background: rgba(91, 58, 166, .32);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

/* 竖向导航框 */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--rail);
  height: 100vh;
  z-index: 78;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: calc(var(--topbar) + 10px) 0 18px;
  background: linear-gradient(180deg, var(--purple-deep) 0%, #1B1330 42%, var(--ink) 100%);
  border-right: 1px solid var(--edge);
  overflow-y: auto;
  overscroll-behavior: contain;
}

.site-nav::after {
  content: "";
  position: fixed;
  top: var(--topbar);
  bottom: 0;
  left: calc(var(--rail) - 1px);
  width: 1px;
  pointer-events: none;
  z-index: 82;
  background: linear-gradient(180deg, var(--gold) 0%, rgba(201, 162, 39, .12) 48%, rgba(201, 162, 39, 0) 100%);
}

.site-nav__list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 5px;
  margin: auto 0;
  width: 100%;
}

.site-nav__item { display: flex; justify-content: center; width: 100%; }

.site-nav__link {
  writing-mode: vertical-rl;
  text-orientation: upright;
  padding: 13px 6px;
  font-size: 12.5px;
  font-weight: 500;
  letter-spacing: .24em;
  color: rgba(247, 244, 236, .74);
  border-radius: 2px;
  transition: color .22s var(--ease), background-color .22s var(--ease);
}

.site-nav__link:hover {
  color: var(--gold-light);
  background: rgba(91, 58, 166, .34);
}

.site-nav__link[aria-current="page"] {
  color: #17110A;
  font-weight: 700;
  background: linear-gradient(180deg, var(--gold-light), var(--gold));
}

.site-nav__utility {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 9px;
  width: 100%;
  padding-top: 20px;
  border-top: 1px solid rgba(56, 64, 92, .5);
}

.site-nav__utility-link {
  font-size: 10.5px;
  letter-spacing: .1em;
  color: rgba(247, 244, 236, .46);
  transition: color .2s var(--ease);
}

.site-nav__utility-link:hover { color: var(--gold-light); }

/* ---------- 7. 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .06em;
  line-height: 1.2;
  white-space: nowrap;
  border: 1px solid transparent;
  border-radius: 2px;
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  transition: transform .22s var(--ease), background-color .22s var(--ease), color .22s var(--ease), border-color .22s var(--ease), box-shadow .22s var(--ease);
}

.btn:hover { transform: translateY(-2px); }

.btn--gold {
  background: linear-gradient(135deg, var(--gold-light), var(--gold));
  color: #17110A;
}

.btn--gold:hover { box-shadow: 0 10px 22px -12px rgba(201, 162, 39, .85); }

.btn--purple {
  background: var(--purple);
  color: var(--porcelain);
  border-color: var(--purple-light);
}

.btn--purple:hover { background: var(--purple-light); color: var(--ink); }

.btn--ghost {
  background: transparent;
  color: var(--porcelain);
  border-color: var(--edge);
}

.btn--ghost:hover { border-color: var(--gold); color: var(--gold-light); }

.btn[disabled],
.btn[aria-disabled="true"] {
  opacity: .42;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

/* ---------- 8. 布局 ---------- */
.container {
  width: 100%;
  max-width: 1280px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

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

.section {
  position: relative;
  padding-block: clamp(56px, 8vw, 120px);
}

.section--tint { background: var(--ink-2); }

.section--slant {
  clip-path: polygon(0 48px, 100% 0, 100% 100%, 0 calc(100% - 48px));
  padding-block: clamp(88px, 11vw, 160px);
}

.section__head { max-width: 68ch; margin-bottom: clamp(28px, 4vw, 52px); }

.section__eyebrow { margin-bottom: 14px; }

.section__title { margin-bottom: 16px; }

.section__lead {
  font-size: 17px;
  line-height: 1.9;
  color: rgba(247, 244, 236, .78);
}

.grid { display: grid; gap: clamp(20px, 3vw, 40px); }

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--7-5 { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }
.grid--8-4 { grid-template-columns: minmax(0, 8fr) minmax(0, 4fr); }

/* ---------- 9. 小构件 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .32em;
  color: var(--gold);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: currentColor;
  opacity: .75;
}

.seal-tag {
  display: inline-block;
  padding: 3px 9px;
  font-family: var(--font-brush);
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: .16em;
  color: var(--porcelain);
  background: var(--cinnabar);
  border-radius: 2px;
}

.seal-tag--gold {
  background: transparent;
  color: var(--gold-light);
  border: 1px solid var(--gold);
}

.rule-gold {
  height: 1px;
  border: 0;
  background: linear-gradient(90deg, var(--gold), rgba(201, 162, 39, .06));
}

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding-bottom: 2px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .06em;
  color: var(--gold-light);
  border-bottom: 1px solid rgba(201, 162, 39, .35);
  transition: color .2s var(--ease), border-color .2s var(--ease), gap .2s var(--ease);
}

.link-arrow::after { content: "→"; font-family: var(--font-mono); }

.link-arrow:hover { color: var(--porcelain); border-bottom-color: var(--gold); gap: 13px; }

/* 切角面板 */
.panel {
  position: relative;
  padding: clamp(22px, 3vw, 36px);
  background: linear-gradient(158deg, rgba(42, 27, 77, .74) 0%, rgba(20, 26, 46, .92) 100%);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
  transition: transform .26s var(--ease);
}

.panel::before,
.panel::after {
  content: "";
  position: absolute;
  pointer-events: none;
}

.panel::before {
  top: 0;
  left: 0;
  width: calc(100% - var(--cut));
  height: 1px;
  background: linear-gradient(90deg, var(--gold), rgba(201, 162, 39, 0) 78%);
}

.panel::after {
  top: var(--cut);
  left: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, var(--gold), rgba(201, 162, 39, 0) 62%);
}

.panel:hover { transform: translateY(-4px); }

.panel--flat { background: var(--ink-2); }

.panel__title {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(18px, 1.6vw, 22px);
  margin-bottom: 12px;
}

/* 书法大编号 */
.num-slab {
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 18px;
}

.num-slab__figure {
  font-family: var(--font-brush);
  font-size: clamp(46px, 8vw, 104px);
  line-height: .9;
  letter-spacing: .02em;
  color: transparent;
  -webkit-text-stroke: 1px var(--gold);
  text-stroke: 1px var(--gold);
}

.num-slab__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .3em;
  color: var(--purple-light);
  text-transform: uppercase;
}

/* 技能树式路径 */
.pathway {
  display: grid;
  gap: 14px;
  counter-reset: path;
}

.pathway__item {
  position: relative;
  padding: 22px 24px 22px 70px;
  background: linear-gradient(120deg, rgba(42, 27, 77, .55), rgba(20, 26, 46, .78));
  border-left: 2px solid var(--purple);
  transition: border-color .25s var(--ease), transform .25s var(--ease);
}

.pathway__item::before {
  counter-increment: path;
  content: counter(path, decimal-leading-zero);
  position: absolute;
  left: 22px;
  top: 22px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--gold);
}

.pathway__item:hover { border-left-color: var(--gold); transform: translateX(4px); }

.pathway__title { font-size: 17px; font-weight: 700; margin-bottom: 6px; }

.pathway__text { font-size: 15.5px; line-height: 1.8; color: rgba(247, 244, 236, .78); }

/* 可展开内容组 */
.accordion { border-top: 1px solid var(--edge); }

.accordion__item { border-bottom: 1px solid var(--edge); }

.accordion__item summary {
  list-style: none;
  position: relative;
  padding: 20px 58px 20px 6px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.5;
  cursor: pointer;
  transition: color .2s var(--ease);
}

.accordion__item summary::-webkit-details-marker { display: none; }

.accordion__item summary:hover { color: var(--gold-light); }

.accordion__item summary::before,
.accordion__item summary::after {
  content: "";
  position: absolute;
  right: 16px;
  top: 50%;
  background: var(--gold);
}

.accordion__item summary::before {
  width: 16px;
  height: 1.5px;
  transform: translateY(-50%);
}

.accordion__item summary::after {
  width: 1.5px;
  height: 16px;
  right: 23.25px;
  transform: translateY(-50%);
  transition: transform .25s var(--ease), opacity .25s var(--ease);
}

.accordion__item[open] summary::after { transform: translateY(-50%) scaleY(0); opacity: 0; }

.accordion__body {
  padding: 0 58px 24px 6px;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(247, 244, 236, .8);
}

/* 面包屑 */
.breadcrumb { font-size: 13px; }

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.breadcrumb__sep { color: var(--edge); }

.breadcrumb__link {
  color: rgba(247, 244, 236, .68);
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

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

.breadcrumb__current { color: var(--gold); }

/* ---------- 10. 正文容器 ---------- */
.prose {
  max-width: var(--measure);
  font-size: 17px;
  line-height: 1.85;
  color: rgba(247, 244, 236, .86);
}

.prose > * + * { margin-top: 1.1em; }

.prose strong { color: var(--gold-light); font-weight: 700; }

.prose a { color: var(--purple-light); border-bottom: 1px solid rgba(139, 107, 224, .42); }

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

.prose ul li {
  position: relative;
  padding-left: 22px;
  margin-top: .5em;
}

.prose ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .85em;
  width: 10px;
  height: 1px;
  background: var(--gold);
}

/* ---------- 11. 图片容器基础规则 ---------- */
.media-frame {
  position: relative;
  overflow: hidden;
  background: linear-gradient(150deg, var(--purple-deep) 0%, var(--ink-2) 55%, var(--ink) 100%);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, 0 100%);
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  border: 1px solid rgba(201, 162, 39, .34);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, 0 100%);
}

.media-frame > img,
.media-frame > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--banner { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame__cap {
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: 2;
  padding: 10px 30px 10px 14px;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--porcelain);
  background: linear-gradient(90deg, rgba(11, 14, 26, .94), rgba(11, 14, 26, 0));
}

/* ---------- 12. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 10vw, 140px);
  padding-block: clamp(48px, 7vw, 88px) 32px;
  background: linear-gradient(180deg, rgba(20, 26, 46, .6) 0%, var(--ink) 42%);
  border-top: 1px solid var(--edge);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: min(260px, 42%);
  height: 1px;
  background: linear-gradient(90deg, var(--gold), rgba(201, 162, 39, 0));
}

.footer__inner {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: clamp(32px, 5vw, 72px);
}

.footer__brandname {
  margin-top: 16px;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 22px;
  letter-spacing: .02em;
}

.footer__tagline {
  margin-top: 6px;
  font-size: 13px;
  letter-spacing: .24em;
  color: var(--gold);
}

.footer__region {
  margin-top: 18px;
  max-width: 34ch;
  font-size: 13px;
  line-height: 1.8;
  color: rgba(247, 244, 236, .5);
}

.footer__cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 40px);
}

.footer__col-title {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .3em;
  color: var(--gold-light);
}

.footer__list { display: grid; gap: 11px; }

.footer__link {
  display: inline-block;
  font-size: 14px;
  color: rgba(247, 244, 236, .72);
  transition: color .2s var(--ease), padding-left .2s var(--ease);
}

.footer__link:hover { color: var(--gold-light); padding-left: 6px; }

.footer__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px 28px;
  margin-top: clamp(36px, 5vw, 56px);
  padding-top: 22px;
  border-top: 1px solid var(--edge);
  font-size: 13px;
  color: rgba(247, 244, 236, .55);
}

.footer__contact { max-width: 74ch; }

.footer__legal {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: rgba(247, 244, 236, .45);
}

/* ---------- 13. 滚动显现 ---------- */
html.reveal-ready [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity .32s var(--ease), transform .32s var(--ease);
}

html.reveal-ready [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 14. 响应式 ---------- */
@media (max-width: 1100px) {
  :root { --rail: 76px; }
  .site-nav__link { font-size: 12px; letter-spacing: .2em; padding: 11px 5px; }
}

@media (max-width: 900px) {
  :root { --rail: 0px; }

  body { padding-left: 0; padding-top: var(--topbar); }

  .frame-top {
    left: 0;
    right: 0;
    gap: 12px;
    padding: 0 16px;
  }

  .brand__sub { display: none; }
  .brand__name { font-size: 14px; }
  .frame-top__cta { display: none; }
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: fixed;
    top: var(--topbar);
    left: 0;
    right: 0;
    bottom: 0;
    width: auto;
    height: auto;
    align-items: stretch;
    padding: 26px var(--gutter) 40px;
    background: linear-gradient(180deg, rgba(42, 27, 77, .98) 0%, rgba(11, 14, 26, .99) 58%);
    border-right: 0;
    border-top: 1px solid var(--gold);
    overflow-y: auto;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(-10px);
    transition: opacity .26s var(--ease), transform .26s var(--ease), visibility .26s linear;
  }

  .site-nav::after { display: none; }

  .site-nav[data-open] {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: none;
  }

  .site-nav__list { margin: 0; gap: 0; align-items: stretch; width: 100%; }
  .site-nav__item { width: 100%; }

  .site-nav__link {
    writing-mode: horizontal-tb;
    text-orientation: mixed;
    display: block;
    width: 100%;
    padding: 15px 14px;
    font-size: 17px;
    letter-spacing: .06em;
    border-bottom: 1px solid rgba(56, 64, 92, .6);
    border-radius: 0;
  }

  .site-nav__link[aria-current="page"] {
    background: linear-gradient(90deg, var(--gold), rgba(201, 162, 39, .12));
    color: #17110A;
  }

  .site-nav__utility {
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: flex-start;
    gap: 20px;
    padding-top: 26px;
  }

  .site-nav__utility-link { font-size: 12px; letter-spacing: .12em; }

  .grid--2,
  .grid--3,
  .grid--7-5,
  .grid--8-4 { grid-template-columns: minmax(0, 1fr); }

  .footer__inner { grid-template-columns: minmax(0, 1fr); }
  .footer__cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  .section--slant { clip-path: polygon(0 28px, 100% 0, 100% 100%, 0 calc(100% - 28px)); }

  .accordion__body { padding-right: 12px; }
}

@media (max-width: 560px) {
  body { font-size: 16.5px; }

  .footer__cols { grid-template-columns: minmax(0, 1fr); }
  .footer__meta { flex-direction: column; }
  .footer__legal { letter-spacing: .04em; }

  .num-slab { gap: 12px; }
  .panel { padding: 20px 18px; }
  .pathway__item { padding: 20px 18px 20px 58px; }
  .pathway__item::before { left: 18px; }
}

/* ---------- 15. 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

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

  html.reveal-ready [data-reveal] {
    opacity: 1;
    transform: none;
  }
}